Full transcript
Air In Oil Overview
0:00Good day everyone. Welcome to
0:00Lubrication Experts. And today, we are
0:02talking about air in oil. Now,
0:05when I teach classes on lubrication and
0:09lubrication management, we often will
0:11talk about contaminants and the
0:12importance of of contamination as it
0:14relates to oils.
0:17Everyone always thinks of particles when
0:19they think of contamination cuz they're
0:20abrasive. Everyone thinks of water
0:23because it's damaging, it's corrosive,
0:24and it collapses oil films.
0:27Everyone might think of soot, glycol.
0:30Um what is probably less appreciated is
0:33air.
0:35Right, so air as it's entrained in oil,
0:38air as it forms foam, you know, foam is
0:40probably the most visible form of air.
0:43And so people because air is all around
0:45us, people don't think of it necessarily
0:47as being a contaminant. And maybe it
0:49hasn't really occurred to you what the
0:51effects on the oil are.
0:52So, today we're going to dispel all of
0:55those notions. We're going to discuss
0:57and you're going to know more about air
0:59in oil at the end of today than you ever
1:01thought you you ever would. So,
1:04now
Meet The Guests
1:05as with this podcast, the thing I love
1:08about doing these podcasts is that even
1:11though people think that my job is very
1:12niche as an industrial lubrication
1:14specialist,
1:15there are infinitely more niches within
1:17industrial lubrication. So, amazingly,
1:21yes, there are experts in air in oil.
1:25And I found them, right?
1:27So, this is the best bit of the about
1:28the podcast that I get to drag these
1:29guys and
1:32and you know, bring them up to the
1:33surface to use an air analogy. And and
1:36and we get to highlight the fantastic
1:38work that they're doing in this field.
1:41So, today I've got Lucas and David.
1:45They're from Evamo. And they've got some
1:48really cool technology which we're going
1:49to talk about a little bit later in the
1:50podcast. That's got all to do with with
1:53air and oil. Maybe Lucas, would you mind
1:55giving me a bit of an introduction just
1:57as to you know, who you are and and what
1:59you do in the business?
2:01Yeah, sure. So, thanks for having us.
2:04My name is Lucas.
2:06I have a background in mechanical
2:08engineering as well as in bachelor's and
2:11also master's degree. After that, I
2:14started my PhD with the topic of
2:16production and detection of oil air
2:18dispersions which is basically just the
2:21topic that we are talking about today.
2:23After that, I directly started at Evamo
2:26as a technical lead for the smart bubble
2:28system project.
2:30And also with the industrialization
2:34of what we are doing right at the time
2:36and of what we have been doing
2:40during the PhD.
2:41And now I together with David, we are
2:45let's say
2:46sort of a double arrow in the
2:49go-to-market and product development and
2:51also engineering. And we are very happy
2:54talking today with you
2:56about what we are doing very
2:58passionately.
3:00Yeah, awesome. And David?
3:02Yeah, hi hi Rafe. Also from my side,
3:05thanks for having us. And also as you
3:07mentioned um
3:08giving us the
3:10possibility to bring air in oil more in
3:12the spotlight. So, yeah, my name is
3:15David.
3:16I'm yeah, the complementary part of
3:18Lucas. So, he's more leading the tech
3:20side of the smart bubble system and
3:23everything. And I'm more responsible for
3:25bringing this yeah, technical topics
3:28more into real life value for customers.
3:30So, my background is has nothing to do
3:33with mechanical engineering, lubrication
3:35oil, or something like that. So, I'm
3:37more from
3:39yeah, a software and
3:40IoT business side. So, with some
3:42previous stations within the Bosch
3:44group.
3:45We will maybe also speak a little bit
3:46more about how Evamo founded. So, yeah.
3:51So, basically I'm responsible for
3:52everything that starts with marketing up
3:55to go-to-market and also sharing kind of
3:59yeah, similar topics with Lucas on the
4:02product management side.
4:03Fantastic. Fantastic. So, I found the
4:06two exact right people to to talk about
4:08this topic. So, you know, we've got to
Air States Explained
4:10start with the basics.
4:12I think everyone is probably aware of
4:14the different forms of air in oil. But
4:17if you wouldn't mind, could you could
4:19you kind of go through the basics so
4:21that we're all on the same page? So,
4:23just like there are different types of
4:24water in oil. So, you've got you know,
4:26emulsified water, dissolved water, free
4:29water, that kind of thing. What's the
4:31state of play when it comes to air? And
4:34I guess you could you could kind of
4:35relate this to other gases, right? It
4:37doesn't just have to be air, but but but
4:39gases inside of oil.
4:41Yeah.
4:42Yeah, maybe we we we put a lot of
4:44thoughts about how to
4:46provide a yeah, real life technical or
4:49more yeah, tangible
4:51examples for this. So,
4:53maybe to start with a well-known
4:54practical example especially from
4:56Germany is yeah, best example would be a
4:58bottle of beer basically. So, if you
5:00look at to a bottle of beer, you
5:02basically have it all. So,
5:04you have the bottle is closed.
5:06>> [laughter]
5:07>> Here's one I prepared earlier.
5:10I wanted to prepare a beer as well, but
5:12I don't know if it's
5:14No, no, we're good. We're good. Here,
5:15I'll crack one open.
5:17I I hope we will do something in in
5:19Germany if we
5:19>> Yeah, yeah, definitely. This one I mean
5:21this is a Hefeweizen. So, so
5:24>> [laughter]
5:25>> Oh, nice. Nice. Yeah, this is in
5:27Australia as well. Cool.
5:28>> Yeah. Yeah,
5:30as I mentioned, best example would be a
5:32bottle of beer because you have it all.
5:34So, starting with the bottle is closed,
5:36you don't see anything that is visible
5:38in your bottle. And as soon as you open
5:41the lid, the pressure drops. And this is
5:44where the air bubbles for example also
5:46get visible. And if yeah, depending on
5:49how how you handle it before, it's
5:52always starting to foam as well. So,
5:54either in the bottle also passing the
5:56head space.
5:57So, basically coming to lubrication oil
6:00again
6:01looking into yeah, studies and
6:03theoretical stuff is that you always
6:05have 8 to approximately 12% of air
6:09dissolved in your
6:12in your air in your oil. So,
6:15under atmospheric pressure and so on.
6:17So, basically chemically bounded. And
6:19depending on temperature and pressure.
6:22But you have different variants. Maybe
6:24yeah, Lucas can also add something on
6:26this. But in practice, people often say
6:29air in oil. But
6:32yeah, it's not just one thing you have
6:33to do to look into the variant
6:36variables. So, because distinction
6:38matters in air in oil especially. And um
6:42it matters because different air states
6:47causing different consequences. And
6:49there are different ways to react on it
6:51and have a response to it. So, yeah,
6:54basically you have to look into
6:56everything.
6:57Yeah, so just as David has said, we have
7:00like four different types of oils of air
7:04inside
7:05oil reservoir. So, for example,
7:08dissolved air which is
7:10the gas that is physically physically
7:12dissolved in the oil and therefore not
7:15not visible. You can calculate the
7:18amount and the percentage by Henry's
7:20law.
7:21Then of course, the entrained air just
7:23when you open the the lid from the beer
7:25bottle, the discrete bubbles dispersed
7:28in the in the flowing flowing oil.
7:32If those bubbles rise to the surface,
7:34they can form the foam
7:37which is the most stable gas-liquid
7:39structure.
7:40You can then see on the surface if you
7:43take a look at
7:44the surface inside your oil reservoir.
7:47And of course, um
7:49the the head space right above the foam,
7:52right above the
7:54the oil surface.
7:56Um
7:57yeah, which can then exchange with the
8:00fluid by by turbulence and all that
8:05Yeah, awesome.
Where Air Comes From
8:06Um this might seem like a very very
8:09obvious question, but uh
8:11where where does it come from? Because
8:13when we talk about something like like
8:15water in oil, we're always trying to
8:18determine where where is that water
8:19coming from? And it could be it's
8:22process fluids. Let's say it's
8:24steam which leaks past the gland seals.
8:26It could be water that is atmospheric
8:29humidity. It could be wash down water.
8:32It could be you know, just simply rain
8:34getting into the drums.
8:36You know, it seems like an obvious
8:37question, but where does the air come
8:39from?
8:40Yeah, this is this is actually
8:43also something that is on the one hand
8:45side pretty obvious, but on the other
8:47hand side not always that obvious
8:50because the air in the oil, it comes and
8:52it goes. And you have different
8:54possibilities where it can come from and
8:56also how you can influence it
8:59if you can even influence it and not.
9:02So, um one side is the already
9:06air content that is in the oil all the
9:08time. So, at atmospheric pressure
9:10pressure, the dissolved
9:13air in the oil that you can of course
9:15not influence.
9:17But on the other hand side, the
9:18mechanical entrained air in your oil and
9:22also if degassing of this at first
9:25dissolved air content is happening. So,
9:29um
9:30for example, if you take the degassing,
9:33this occurs when the dissolved
9:36air
9:37comes out of your oil. And this happens
9:41when pressure drops, when temperature
9:43also shear conditions change.
9:47On the other hand side, the mechanical
9:48entrainment can come from
9:51for example, if your gears splash inside
9:54a inside a gearbox.
9:57The churning effects,
9:58by aggressive flow conditions inside
10:01your hydraulic system.
10:03If you have a sealant leakage at suction
10:05side of pumps,
10:07or also if you have uh return line
10:09splashing
10:10in your hydraulic systems.
10:12>> And
10:14this is also also um if I can add
10:15something to this. So, um if you look
10:17into particles, for example, of if you
10:19look into water,
10:21um if the oil [clears throat] comes to
10:22your facility, for example, um I think
10:25you can
10:26hope or you can be sure that there's not
10:27there are no particles or water, but in
10:30the field, for example, if we look into
10:31air, air is often seen to be appear out
10:34of nowhere. So, if we're um again
10:36speaking about the air in hydraulic oil,
10:38this is is there anyway?
10:41Um you have the gas often already as um
10:45um
10:45um of of your system, it's part of your
10:47system if you're filling up it up. So,
10:50the operating points um ultimately push
10:53it to
10:54um a more problematic regime in the end.
10:56So, that's why where it comes from is
10:59only half the story, but uh when and
11:01under which conditions it becomes
11:03visible is uh yeah, as as is important.
11:07Mhm. Okay.
11:08Interesting. And then, what about what
Oil Chemistry Effects
11:11about the effects of different types of
11:12oils? So, you know, you've got different
11:15oil chemistries, so different base oils.
11:17Um there's also different additives.
11:19Now, I mean, with my limited knowledge,
11:21I would assume that uh
11:24uh different um
11:25let's say, for example, in refrigeration
11:27lubricants, where we're usually trying
11:29to match the base oil to the type of gas
11:32that's being compressed,
11:33um because you don't want interactions
11:35between the two. So, some gases are more
11:37likely to dissolve in in certain base
11:39oils than others.
11:41Uh and then you've also got surface
11:42tension effects, right? Whether that's
11:44from, you know, the detergent
11:45chemistries or what have you. So,
11:47what is the effect of the actual oil
11:50itself um on the type of air or or the
11:54the nature of let's say the the volume
11:55of air or the the type of air
11:58contamination that that you end up
12:00getting?
12:01Mhm.
12:02Yeah, so this is
12:04in my opinion, one of the of the biggest
12:07effects. Um so, the type of oil and also
12:10the the additive packages that are
12:12inside of the oil. And this is, of
12:15course, all the knowledge the the oil
12:17manufacturers have.
12:19And um
12:21all the time they try to fit the the
12:24performance of the lubricants to the
12:26application they are used for.
12:28So, um
12:31at a very high level,
12:32and also for for modern industry oils,
12:37those are formulated to balance several
12:40functions at once.
12:41So, um
12:43each time with the main goal to fit the
12:45application and the used oil in your
12:48application.
12:49So, for example, if you have high load
12:51carrying and wear protection, you need
12:54to have a lot of oxidation resistance
12:57and thermal stability,
12:59viscosity control with regards to the
13:01temperature inside your application.
13:05Um in the end, if you have a lot of
13:06additives inside your oil,
13:09foam control and the air release
13:11behavior, of course, is is a very very
13:14high
13:15um goal to achieve.
13:17And um
13:19those additives,
13:21they work different and also in
13:23different ways with regards to the air
13:26release behavior. So,
13:29um
13:30for example, if you use the
13:32the the extreme pressure or also
13:34friction modifiers chemistry,
13:37um
13:38those are then used for the mechanical
13:40load handling and also for the friction
13:41behavior. If you take the anti-foam and
13:44deaeration chemistry,
13:46those can handle the the foam then
13:48tendency and also the the gas handling.
13:51If you use the viscosity improvers, they
13:54change the the temperature viscosity
13:56behavior, so how quick also the bubbles
13:58can rise to the surface.
14:01Um and
14:03one of the biggest
14:05points that is really to highlight is
14:07that um
14:09the formulation is always a balancing
14:11act and not
14:13one single objective optimization. So,
14:17um
14:18everything you put inside your oil
14:21um is also changing the surface tension.
14:24And this surface tension is then
14:26influencing how the oil is interacting
14:29with the air inside it. So, it
14:32it influences a lot
14:34um what happens with bubble breakups,
14:37with coalescence behavior,
14:39um what is happening with the surface
14:42activity of the oils and also for the
14:44long-term thermal performance of your
14:47application itself.
14:48So, um
14:51in this case, the air handling of the
14:54oil or of the application is not just a
14:56mechanical question. This is basically
14:59inside the formulation of the oils
15:00itself.
15:03Yeah, and uh yeah, like like Lucas
15:04mentioned, uh so it mostly comes from uh
15:07experience when it comes to lubricant uh
15:10formulation, for example, if yeah, they
15:12are adapting, for example, to a specific
15:14machine or application.
15:16But uh we also found out that two
15:18systems can have have uh very similar
15:20had hardware, but still behave
15:22differently when it comes to
15:24um air ingress.
15:25And uh because then the fluid behaves
15:28differently, um like I don't know, for
15:30example, formulated in the lab. So, not
15:32every, for example, ISO VG 46
15:35um behaves the same once air enters, but
15:38um yeah, that means air handling is,
15:40like Lucas said, not a mechanical topic
15:43always, but um lubricant formulation
15:45topic.
15:46Yeah, interesting. Interesting. Yeah,
15:49I'm you know, it's maybe something
15:50that's a a little underappreciated,
15:52because, you know, and we'll get into it
15:54when we start talking about measuring
15:56air in oil, but people just see a a foam
15:58number and an air release number, and
15:59they kind of call it a day, right? So,
16:02um
16:03uh but I'm sure that it's that's uh
16:04we'll get into that in a little bit more
16:06detail in a second. So, so we've now
Why Air Matters
16:08established obviously there's there's
16:09different types of air that enter the
16:11oil system. Um you know, we classify
16:14them by by the way that they present
16:15themselves inside of the oil. And I
16:17think everyone will have seen various
16:19versions of this.
16:21Um
16:22then I guess it sort of begs the
16:23question, well, I always say to to my
16:26customers that they should always be
16:27asking, "So, what?"
16:29Right? So, so I have I have oil in uh
16:31let's say, for example, I have
16:32oxidation. So, what? Like, what do I
16:35care about that?
16:36Um so, in this instance,
16:38we have air entering our oil system. So,
16:40whether it's entrained, whether it's
16:43foam, whether it's dissolved air,
16:46so I'm going to ask you the question,
16:47"So, what? Like, what do I care about
16:49that? Why why does it why does it matter
16:51to the performance of the oil? What's
16:52the effects
16:54of that?" Mhm.
16:55Yeah, pretty good question. Um it's
16:58always uh also one thing that we we get
17:01to ask a lot. So, um
17:04we always um
17:07differ between the long-term and also
17:09the short-term effects of the air inside
17:12your system. So, um if you take a look
17:14at the short-term,
17:16um always mechanical damage mechanisms,
17:20they come at first. So, uh if you take a
17:22look at cavitation, microdieseling, also
17:25the efficiency impact of the air inside
17:29your oil, those are very high. So, for
17:31example, if you take the cavitation,
17:33um by increasing the compressibility,
17:37which happens if you put air into your
17:39oil,
17:40um you catalyze the start of a
17:42cavitation. So,
17:44um by reducing the suction height, for
17:47example, this happens a lot by putting
17:50higher air contents into your oil.
17:52Um if you take a look at the
17:53microdieseling, high pressure loads
17:56that uh compress the oil-air mixture and
17:59then produce high temperatures that can
18:02also damage your oil, of course.
18:04Um by hydraulic efficiency, if you
18:07increase the air content, also the
18:10volumetric efficiency of your pumps
18:13isn't the same anymore. So, um
18:16by taking a look at
18:18how much air is inside your system, you
18:20can then take a look at what happens in
18:23short-term.
18:24Um and of course, just as you have said
18:27it at the time, the long-term
18:30um problems are, of course, the
18:32oxidation, because um if you take a look
18:34at uh temperature, catalytic uh metals
18:38or particles,
18:40those
18:41um if this comes together with the
18:42contact surface between the air and the
18:45oil, which is the reactive layer,
18:47um of course, this is only directly
18:50measure measurable.
18:52Um the
18:54the
18:55the thing together is pretty logic. So,
18:58um
18:59increasing the air content also
19:01increases the oxygen availability for
19:04the reaction.
19:06And um
19:07by the air-oil interfacial area, which
19:10defines then the reactive layer for the
19:12oxygen, in combination with the heat
19:15residence time, catalytic surfaces, and
19:19also the contamination,
19:21um the oxidative stress is catalyzed a
19:23lot.
19:25Yeah. Also, you get potential
19:27consequences, including viscosity
19:29shifts, additive depletion, acid
19:32formation, deposits, varnish, and and
19:35all that stuff. So, this is always in in
19:38correlation with with air contents.
19:42Yeah, and just maybe to I got to write
19:44that one um for with regards to
19:47oxidation, for example, oil oil aging,
19:49if we see that that change, for example,
19:51so
19:52um if you do not look into the oil
19:54directly, so really optically you do not
19:56see or can derive cannot revise the oil
19:59air contact surface.
20:01And this is
20:02especially the oil air contact surface
20:04is
20:05is
20:07gaining speed and and and leading in the
20:09end to oil oxidation, oil aging, and
20:12then this ultimately has also an effect
20:14of
20:15yeah with regards to efficiency.
20:17So um
20:19we will talk a lot a little bit more
20:21about that topic, how we are doing it
20:23and how we are doing it optically and
20:25the oil air contact surface is one of
20:27the yeah advantages that is coming out
20:30of our methodology we are using for
20:32detecting air in oil.
20:34Yeah, that's that's so interesting. I
20:35mean, I think
20:37cavitation, micro-dieseling,
20:40you know,
20:41air locks,
20:43loss of hydraulic efficiency. I think
20:45everyone kind of just associates that
20:46with hydraulic units, right?
20:49Um
20:49I mean, I have seen cavitation between
20:52gears.
20:53Uh I think a lot of people might have
20:55seen that those videos on the internet.
20:57Um
20:59and and obviously you can see how those
21:02would translate into other applications.
21:04I think oxidation is maybe a less
21:06obvious one. Um
21:08but it it stands to reason when you
21:10think about it because obviously
21:12at a very basic level oxidation requires
21:14oxygen.
21:15In order to add oxygen to the oil
21:17molecules, you need to have a source of
21:19oxygen and most of the time that's the
21:21air. And so
21:23the less
21:24oxygen exposure you have to the oil, the
21:26less oxidation happens.
21:28But maybe it's a it's an
21:29under-appreciated
21:31fact.
21:32>> That that's that's two two good examples
21:34for that. So every everybody knows it
21:37for example from a banana. If you look
21:38into a banana and then
21:40um you're getting it out and it has
21:43contact to to the air, for example, then
21:45it gets yellow or brown and the same
21:48actually happens also to the oil. So it
21:51ages with contact to to the oxygen or
21:54gas or anything else.
21:55And
21:56then coming to my second example,
21:59everybody knows how
22:01hard it is to to swim, for example, but
22:04if you compare now for example swimming
22:07swimming through water, it's something
22:08different like swimming to honey. So
22:12if you have a more contact bigger
22:13contact surface uh
22:17um the oil ages faster
22:19then the viscosity is changing and then
22:21you need more input for getting the same
22:23output. So for example, if we're talking
22:24about wind turbine gearboxes.
22:27Yeah. Yep, interesting. So yeah, so I
22:30think
22:32yeah again, it's one of those things
22:33where maybe this is under-appreciated of
22:36the the effects that
22:38that we can have between
22:40air and the oil system.
22:42So so we've established
Reducing Air Exposure
22:45what kind of air
22:46actually gets into the oil.
22:48And then now I think we've given enough
22:51evidence to say
22:53can be a bad thing, right? In some cases
22:55it's going to be unavoidable, but but
22:56but can be a bad thing. So now let's
22:59talk about the techniques that we have
23:00in our toolbox
23:02to reduce the amount of exposure that we
23:05have between the air and the oil system.
23:06So so what can we do to prevent foam?
23:10What can we do to prevent air
23:12entrainment? What Ultimately, what we're
23:14trying to prevent is is the is the
23:16damage through oxidation, cavitation,
23:18micro-dieseling, loss of hydraulic
23:20efficiency, etc. So so what are the the
23:22tools that we have in our toolbox in
23:24order to accomplish that?
23:26Yeah, we quite often hear that question.
23:30So the industry is often looking for a
23:32silver bullet, but air in oil is rather
23:35a
23:36one variable problem.
23:38Um so you usually need to look into a
23:41layered approach. So on the one hand
23:42side as we already
23:44um
23:45described it, we have the hardware side.
23:47So there are different techniques for
23:49reducing like more well-known changing
23:52the reservoir design,
23:54optimizing the return line geometry,
23:56de-aeration zones, and maybe also coming
23:59to a practical example from one of our
24:01projects is the shaft suction condition.
24:04So for example, we had a
24:06measurement request for a pump
24:09manufacturer
24:10from Austria and they are providing
24:12their pumps for example for submarines.
24:14So it's obvious that you do not want
24:17noise and you do not want to have any
24:19wear
24:20or damages in in your system.
24:22And so they always tried to optimize
24:26their design of their pumps with regards
24:28to cavitation by really changing the
24:32design and geometry of the pump.
24:34But they never looked deeply into the
24:36suction condition. So um with with our
24:40test benches where we either have the
24:41chance to reproduce the air content, so
24:44we really can ingress it in a controlled
24:46manner, we could then found out that
24:49their specs that they defined for
24:51withstanding so how much air
24:53can be in their pumps was totally wrong.
24:56So they declared or specified their
24:58pumps with 9% for example and we we
25:01approved it that it's not even reaching
25:035% of of air in oil until it starts to
25:06cavitate. So they really followed the
25:10wrong technique since more than 5 to 10
25:12years and yeah but because they didn't
25:15measure it. So every time they had a
25:17issue in the field, they sent out a
25:20service mechanism
25:22for example or technician.
25:23And
25:25they flew to the problem to the
25:26application, changed the pump and so on
25:28and so forth.
25:29So
25:30yeah, the suction condition for example
25:32and the return line geometry is
25:33something really important. So on the
25:36one the other hand side we have the
25:37fluid. So for example, the technique
25:40would be
25:42better understanding and changing the
25:44viscosity for example or we have
25:46influences in the air release behavior
25:48and
25:49also for example additives like
25:51anti-foam chemistry that is used to
25:54reduce the effects of air in oil.
25:56So in the end it's usually really a
25:59combination of the fluid system of the
26:02fluid the chemistry, the system design
26:04and also the operating conditions.
26:07So yeah.
26:09I think that's that's that are the most
26:11well-known but also I don't know tips
26:14from from our side.
26:16Yeah, interesting. Really interesting. I
26:19mean, there's obviously some some some
26:21other like
26:23chemistry tools that we have in in our
26:25toolbox in terms of you know, anti-foam
26:27agents and obviously you can affect air
26:29release properties by
26:32but even even as basic as as the the
26:34viscosity of the oil, right? So high
26:36viscosity oils are going to release air
26:38bubbles a lot slower.
26:40Yeah. Can you can you talk also I mean,
Reservoir Design For Air
26:42one thing that you just talked about was
26:44the
26:45basically suction line design.
26:48Right? What about the effect of the
26:50actual reservoir itself?
26:53So I mean, the way that I've always
26:54taught it to to students is like you if
26:58you had two choices, right? So every
26:59everything else holding every other
27:01other thing equal, we've got two systems
27:03that are identical and in one you've got
27:06a reservoir that is
27:08you know, same volume but wide and
27:10shallow and you've got another reservoir
27:12which is tall and skinny.
27:14You know, which one do you think is
27:15going to generate more foam?
27:17Just as a bit of a thought exercise.
27:20Now that's obviously taking it to the
27:21extreme.
27:23But what kind of best practices I guess
27:25do you guys see in terms of
27:27reservoir tank design?
27:31Yeah, so just as you as you mentioned,
27:35I think the
27:36the worst case would be a very high
27:38tank,
27:39very high
27:41oil reservoir with uh
27:43suction and pressure inlet on the same
27:46height um with the same um
27:50volume flow. This would be pretty bad.
27:53So
27:54the things that that would work quite
27:57well is if you take just a look at the
28:00the height the bubbles have to
28:02um
28:03have to
28:04walk through to get to the surface to
28:07get out of the system and also the
28:10distance they have to travel to get back
28:13into the suction line. Um if you take
28:16those few variables, it can get pretty
28:19easy for you to optimize such a system.
28:22Also if you take
28:24a look at the amount of um
28:28of oil that is sucked into your system
28:30and also fed back Yeah, interesting.
28:33Interesting. So so
Why Lab Tests Fall Short
28:36if I had to kind of
28:38if I'm an if I'm an end user, right? So
28:40and I'm looking to troubleshoot, we need
28:43standardized methods to be able to
28:45measure
28:46air in oil.
28:48Um to my knowledge at the moment like
28:51when
28:52when I look at different test methods,
28:54I'm basically looking at foam sequence
28:56testing and air release testing.
28:58Right? And and that's basically the
29:01extent of the toolkit. So could you
29:03please help us understand you know, what
29:06those are for?
29:07And now obviously you guys have
29:09developed
29:11a system outside of that. So what was
29:14the
29:15what was the gap that you saw or what
29:17what what about the current tests like
29:20makes it incomplete?
29:23Mhm.
29:24Yeah, so this is always the thing
29:27as you have mentioned the air release
29:29behavior of the oil so also the foam
29:31tendency with the three sequences.
29:33Um this is always the the point of view
29:36from from lab.
29:37So what we are also doing is taking a
29:40look at the field. So what is really
29:42happening with the oil inside the
29:44application and
29:45um on that point we have different types
29:48of measurement possibilities.
29:51Um, on one hand side, you have the
29:54indirect measurement
29:56methods. So, if you take a look at, for
29:59example, electrical constants like the
30:02electricity, capacitive, also
30:04impedance-based methods.
30:07Uh, you can track a change change of
30:10your of your fluid or of the mixture
30:14inside your measurement device and refer
30:17this to an air content in your inside
30:19your system.
30:21Um, you can also use light-based
30:22methods, acoustic response-based
30:25indicators, and all that stuff.
30:28Um, this was also the first way to go
30:31um, in our
30:33um, development, but uh, we could really
30:37not find a way to reproduce the
30:39measures, but also to to really validate
30:42optically what was happening inside our
30:45systems.
30:46So, this was the point to really start
30:49with a direct measurement method.
30:51Um, and this is what we are doing. So,
30:54we are are really taking pictures of the
30:56oil-air mixture and then evaluating
31:00um, each and every bubble that that we
31:03can measure. Yeah, interesting. Uh, can
Indirect Sensors Calibration Trap
31:06I just uh, uh, step back cuz you
31:08mentioned impedance type sensors or kind
31:11of you know, electrical property
31:12sensors. This is something that I've
31:14seen a fair bit, um, you know, not
31:16adjust for identifying air content in
31:19oil, but also oil degradation,
31:22uh, contamination, all that sort of
31:24stuff. I mean, um,
31:26uh, there's a there's a few of these
31:27sensors, whether it's impedance or
31:29resistivity. Uh, and it's always struck
31:31me that you're getting a single number
31:33out, right? It's, you know, kind of
31:34electrical property up or down. Yeah.
31:37But, but
31:38like water should affect that and air
31:40should affect it and contaminants should
31:42affect it and oil degradation could
31:45affect it. You you know, in in the
31:47conception of how these sensors work,
31:49how are you identifying a single failure
31:51mode? Or or can it not be done?
31:55This is this is the exact problem we
31:57also see here, um, because, um, how do
32:00you want to interpret a value that is
32:02changing by so many uh, side effects?
32:06So, um,
32:07um, when we started the project, we also
32:10started with with those um, electrical
32:12constant measurement devices
32:14and
32:16we had more to do with the calibration
32:18of those sensors
32:20than with the measurement itself. So,
32:23this was
32:24this was very crazy and um, therefore,
32:27it was it was really not
32:30for us a thing to
32:32to develop a new type of sensor system
32:35to integrate into into applications, but
32:38really to solve a an issue that we had.
32:42Yeah, and the issue is not only is not
32:43only with regards to data or to
32:45technology, but
32:47yeah, with regards to my role of
32:48functional function is
32:50yeah, the more the gap with regards to
32:52the customer value. So, the field
32:54problem is is highly dynamic, but many
32:57methods like Lucas already mentioned,
33:00um, are indirect, for example, or
33:02difficult to interpret physically under
33:04changing conditions, for example. So,
33:06for us, it was really important to not
33:08just provide um, a test bench that can
33:11use can be used in one environment, but
33:14from lab to testing to field and and
33:16even to simulation. So, um, and this is
33:19quite hard with the current um, yeah,
33:22technology that that are on market
33:23because the issue is not that the
33:25current methods are useless.
33:27And um, the issue is more that they are
33:30often not close to not closing the loop
33:32between symptoms, the actual air states
33:35in the field especially, and also the
33:37engineering action. So, currently, if
33:39you look into, for example,
33:40die-dielectricity
33:42technologies, uh, you just get one um,
33:45variable or KPI like you mentioned, but
33:47you don't do not know what to do with
33:50it. So, for example, how to derive some
33:52engineering actions.
33:54So, the market does not lack sensors and
33:56data, but
33:57we are calling it really one a one data
34:00language. So, we can use our system in
34:03the lab. We can for early days testing,
34:05for example, and we can use it in the
34:07testing. If you, for example, want to
34:08specify a specific lubricant for your
34:11pump,
34:13and we can also then um, get some
34:15results from the field how the pump is
34:17actually working um, or behaving with
34:19this specific lubricant.
34:21So, um, this I think is the gap that we
34:24are closing especially not from also not
34:26only from a technical point of view, but
34:28really when it comes to customer value
34:30in the end.
34:32Yeah, that's that's really interesting.
34:33I mean,
34:35like you said, you know, closing the gap
34:36between between the lab and and and what
34:38what the reality of the situation is.
34:40The example that I always kind of give
34:42to to clients and customers and and
34:45students is you you know, as an example
34:48would be foam,
34:49right? Um, so, people their hair seems
34:53to set on fire for some reason when it
34:55comes to foam,
34:56uh, even though it's probably a little
34:58hopefully be more benign than entrained
34:59air, but but uh,
35:03the statement that I always kind of give
35:04them,
35:05maybe you guys can tell me if I'm
35:06telling them the wrong thing, but I
35:07always say, you don't have
35:10a foam problem until you have a problem
35:13with foam,
35:14right? And that seems like a an odd
35:16thing to say to them, but but what I
35:19mean by that is
35:20um, just because the lab result is
35:24telling you that foam sequence is
35:26degraded, right? Compared to the new
35:28oil, that doesn't necessarily mean that
35:30you actually have a foam problem. Like,
35:32go and look at the reservoir.
35:34You know, if there's no foam, you're
35:36fine.
35:37Uh, just because the test tells you that
35:39there is the potential for foam, uh,
35:42doesn't necessarily mean that you run
35:43into a problem in the real world. And
35:45even if you have foam, that's like the
35:47oil naturally releasing the air. So,
35:50until you have problems, you know,
35:52controlling the level of the oil in the
35:54sight glass or you know, the foam is
35:56getting sucked into the the suction side
35:58of the pump or the the foam is spilling
36:00out um,
36:02of the of the reservoir,
36:05you know, you don't actually have a
36:06problem yet. Um, and so, it's good to
36:09see it's good to see someone who's who's
36:11looking to close the loop. So, speaking
Smart Bubble Origin Story
36:13of, right? You guys have developed a new
36:15system
36:17um, for I guess measurement and and
36:19modeling of air in oil. You hinted
36:22already that it's kind of an image-based
36:24system and we're able to to to look at
36:27different air bubbles and categorize
36:29them, but could you please just go into
36:31a little bit more detail on like how it
36:32works and and maybe where did it come
36:34from, too? Cuz, you know, all
36:36technologies kind of have a an origin
36:38story for want of a better word. Yeah.
36:41Mhm.
36:41Yeah, so, um, just as we we've said
36:44before, the the origin of the of the
36:47measurement device itself, um, was more
36:50practical than a problem-related
36:53topic. So, um, within the pump business,
36:57um, from Iwam we had
36:59a lot of
37:01um, tests we had to do with the pumps
37:04related to the air inside transmission
37:07systems.
37:09So, customers always said, you have to
37:11guarantee that your pumps withstand like
37:1540 to 50% of air, sometimes 30% of air,
37:18which is pretty crazy if you really take
37:21a look at gearboxes.
37:23Um, and
37:25there we tested several
37:27um, devices for measuring, also several
37:30possibilities for for reproducing and
37:34none of them really worked for us
37:36because of um,
37:38cross-contamination,
37:40particles, water content, all that stuff
37:43that you have already mentioned before,
37:45that you already know from from your uh,
37:47side of view.
37:49Um, and because to repro-
37:51reproducibility,
37:53um,
37:54was really not sufficient and also we
37:58had a a constant need of calibration of
38:01our sensors.
38:02Um,
38:03we had to
38:06we really had to um, find a way for us
38:09to develop such a such a measurement
38:12system.
38:13And um,
38:14this is also or this was the point where
38:17I I started my PhD and so, um, the
38:21original problem was not
38:24that we really needed a new sensor.
38:26Yeah.
38:27Yeah, but yeah, maybe I I can add
38:29something with regards to Iwam. So, um,
38:32yeah, basically, we we both work on the
38:34smart bubble system, but the history of
38:37Iwam is quite interesting also with
38:38regards to this topic because um, for 5
38:41years yeah, so,
38:43yeah, ex-
38:44yeah, 10 10 10 days before the the fifth
38:46birthday. So, 5 years ago, uh, we got
38:49bought um, from an investor from Unic
38:52and we're a former Bosch business unit,
38:55um, yeah, producing, manufacturing, and
38:57selling um, steering pumps and
38:59transmission pumps. So, um, in the CV
39:01sector, so commercial vehicle steering
39:03um, pumps, we are market-leading
39:05company, um,
39:07especially in the western hemisphere.
39:09And um, but Iwam itself is is quite
39:11unknown, uh, but to be honest, they're a
39:14hidden champion in in that way. So, um,
39:17as Lucas mentioned, um, it really came
39:19out of an own problem. So, we didn't
39:21develop a solution out of nowhere, but
39:23we really had the same issue
39:26um, like the others that we can see now.
39:28So, the problem was not, as mentioned,
39:30um, to buy another sensor that we can
39:32test, but the real problem was really
39:33the incomplete visibility of uh, what is
39:36happening in our pump. Um, and that we
39:39needed for decision-making. So, the team
39:41had lab test like you mentioned um, we
39:44had field we had field testing with had
39:48a sensor for the testing but there was
39:50still the gap between we suspect air and
39:52we really can quantify the air bubbles
39:54in our system. And that matters really
39:57commercially also with regards to to
40:00hidden cost factors to hidden fluid side
40:03variables that can inside or can can sit
40:06inside a very expensive downtime chain.
40:09So
40:11this is this is also also with regards
40:13to what I mentioned to the different
40:15environments is
40:16that
40:18you also mentioned it yourself so we do
40:20not want to generate a next sensor zoos
40:23because there are so many sensors on the
40:24market but the gap is really that if
40:27you're for example using the 9120
40:30so the
40:31air release ISO test in the lab so
40:34you're measuring it for example with
40:35density but in the testing you're then
40:38using a dielectricity sensor and in the
40:41field you do it something like different
40:44so we want to really
40:46establish and bring the more spotlight
40:48into air and oil but not only for the
40:51field where the volume is but also to
40:53really
40:54to really show that we are understanding
40:56the air and oil phenomena in different
40:57environments so really starting with lab
41:00going to the testing and also to the
41:04field.
How Image Measurement Works
41:05Yeah so maybe explain how the system
41:07works right because you've already
41:08mentioned that it's like image based
41:10right so we're we're we're capturing
41:12actual images of the air bubbles but I
41:14think maybe
41:16it might be a little bit difficult for
41:18for some viewers to understand what it
41:20means to be able to take the same
41:21technology which is image based and and
41:24what does it mean to have it in the lab
41:26but also in the field like what
41:29what is the technology and how are you
41:31looking to deploy it?
41:33Yeah so at a very high level
41:36we're basically sucking oil out of the
41:40the oil reservoir and then we define
41:43specially defined measurement path
41:45controlled optics and specially designed
41:47illumination concepts
41:49yeah to make the dispersed air
41:55structures visible
41:57and this with high
41:59consistency and accuracy and
42:04just like this you can really
42:07have a reproducible but also
42:09understandable result so that you don't
42:12have to interpret and think about yeah
42:15maybe my my water content got also a
42:17little up and so my the electricity
42:20changed a little bit we have to
42:22recalibrate and all that stuff so we
42:24just plug it to the application suck the
42:27oil out measure it and
42:30that's that's mainly it.
42:32And this is really the advantage because
42:34you mentioned that
42:35currently with the current technologies
42:37you just have one single data so it's
42:41just for example if we would looking
42:42into the air release behavior with the
42:44lab environment again you have the any
42:46density topic and you have the time
42:50which which is measured but we are not
42:52only looking into air content or air
42:55volume because you can either have 5% of
42:57air content in your oil with with
43:00smaller bubbles and but you can also
43:02have 5% of air volume in your oil with
43:05smaller bubbles.
43:06So this really depends and this is also
43:08the the advantage of our system in the
43:10end because we are not only detecting or
43:12counting the bubbles
43:14but we are looking really into every
43:16each and every air bubble in in your
43:17system or in your oil so we are counting
43:20them we are classifying them or modeling
43:23them and yeah we have the size
43:25distribution we have the contact surface
43:29of each and every air bubble and into
43:31the fluid
43:32and so this really makes the difference
43:35if we look into
43:38into measuring the air in in the field
43:40and then we can really use that one data
43:42language
43:44to have more clear insights into what is
43:47happening in your lubricant but also in
43:49the hardware system
43:51and
43:52the key difference here just to add this
43:54one as well is that we're not just
43:56measuring a proxy that tells you
43:58something has changed in the system or
43:59something gets noisy or something like
44:01that we really try to make the the the
44:06topic of air or air bubbles
44:08more observable but in the end and this
44:11is the most important topic is more
44:13explainable and actionable so instead of
44:16just saying the the system sounds wrong
44:18or
44:20I don't know the vibration is
44:22influenced or impacted you can really
44:24say see and say how the air is behaving
44:27in different systems but all
44:35detect but also interpret
44:37and actionability is one of the key
44:39points here.
44:41Yeah interesting so so
Turning Data Into Actions
44:43you know when whenever I'm explaining
44:45condition monitoring I always say uh
44:47you know a a blood test is only useful
44:49if you act
44:51on
44:52the data right so if you if you get a
44:54blood test and it says you have high
44:55cholesterol and you continue to not
44:58exercise and and eat the same rubbish
45:01food that you always have then
45:04nothing's changed right
45:06so so that's the key thing right you you
45:07mentioned the word actionable.
45:09So so what are the kind of things that
45:12customers would typically be doing in
45:14response to the data that they get from
45:17the smart bubble system so
45:19you know you mentioned it obliquely
45:20before wind turbines so I've got a wind
45:23turbine I I I take these measurements of
45:26the air bubbles you're giving me a lot
45:28of data on you know contact surface
45:32you're giving me the size of bubbles the
45:34distribution of the size of the bubbles
45:36and the total volume as well.
45:39Okay now what do I do with that those
45:41numbers?
45:44Yeah this is is a very
45:47interesting thing because
45:49each time you want to optimize something
45:52you have to know what you really want to
45:53optimize so you have different paths
45:55that you can go so for example if you
45:58want to do a thermal
46:00optimization
46:01if you put air in inside of your oil the
46:06thermal conductivity is changing a lot
46:08so if you have a lot of isolating air
46:11inside your oil the cooling needs a lot
46:13of energy.
46:15When we are then at the energy if you
46:17put a lot of air inside your oil the
46:21viscous effects regarding to to power
46:25loss is also changing a lot because on
46:27the one hand side your filling level
46:29changes therefore the resistance of your
46:31gears inside the gearbox is changing a
46:33lot
46:34on the other hand side if you want to
46:36change the long term
46:38issues
46:40with regards to to air content for
46:42example the oxidation the temperature
46:45and also the contact surface between the
46:47air and the oil is influencing this a
46:49lot.
46:50Also how your oil is performing with
46:53regards to
46:55temperature and air contents so we have
46:58plenty different of measurements
47:01where you can really see
47:03the behavior of the oil
47:06with regards to the air release behavior
47:10with temperatures so not each oil is
47:14performing the same so with with
47:16increasing the temperature the air is
47:17getting out much more quicker some oils
47:20with some additives can then keep the
47:23air much better because the the air
47:26bubbles get much smaller.
47:28So those are the topics that you really
47:30have to define with the customer
47:33and then you can point at them very
47:36easily and then you can also optimize
47:38them the way that you want to do it
47:41but only with a measurement and this is
47:43this is the key point.
47:46Yeah interesting so so I mean the types
47:47of optimizations that you're talking
47:49about I guess probably weren't possible
47:53in the past right because we've never
47:54had
47:55that kind of data
47:57to be able to play with
47:59and I suspect you know it's it's one of
48:02those situations where
48:03when you measure the data you find uses
48:06for it as well
48:08maybe that were a little unexpected so
48:12So so one good example is for example if
48:14you are for example looking to the air
48:15release value measurement
48:17methodology or techniques that they are
48:19currently established
48:20they are missing quite most of the
48:24the most important
48:26sections of the diagram so if you look
48:28for example into the ISO 90 9120 you
48:31just get the line that is decreasing and
48:34then it tells you how much it how much
48:36time it took to get to the 0.2
48:39percentage of air density
48:41and
48:42we are really really looking not into
48:44this declining
48:46line but also the beginning the peak and
48:50the first 10 10 10 seconds for example
48:53so this is really giving you then the
48:55advantage here so it's more not only
48:58more trustworthy but more honest
48:59technology so because you can really see
49:02what is happening and if you're not
49:03trusting your diagram for example you
49:05can see which which kind of image which
49:08kind of condition were there or air
49:10regime when you
49:12when you
49:13measured your lubricant for example.
49:16So
49:17and if you look for example in the field
49:19we can also provide a dynamic air
49:21release value so then you can correlate
49:23what is happening in the lab in the
49:25field but also you can then correlate
49:27the air release behavior with the oil
49:30oil air contact surface
49:32so
49:33rather you have a air release that is
49:35happening fast
49:37seeing also the air contact surface or
49:39air contact surface that is then showing
49:41you do you have more like bigger bubbles
49:43that are the cause of the good air
49:45release or do you have still smaller
49:47bubbles that are more
49:49harmful to your system and also
49:51infecting or influencing the the air
49:53release behavior.
Deployment And Scaling Vision
49:55And and how you seeing the systems
49:58deployed for the most part, right? So I
50:00can imagine the way that you've
50:03described it is that you're taking oil
50:05from the reservoir
50:07obviously in a very controlled manner
50:09in order to be able to do the
50:10measurement. So in a sense, that's kind
50:13of an inline unit, right? Because it's
50:15giving you effectively real-time data.
50:18Is that
50:20usually going to be you know attached
50:22just for diagnostic purposes and then
50:25that gives us a window into the current
50:27state and then we can go and make fixes
50:29or are you guys looking at this as a
50:32more permanent solution? Like how how
50:33are they being deployed?
50:36Yeah, this this is this is a good
50:37question interesting topic. So
50:40maybe strange that coming from a more
50:42business-related person but we do not
50:45want to scale it just for more devices
50:47for example.
50:48So we really want to see that or show
50:51that we are really
50:53putting the spotlight on air in oil
50:56getting to know it more better
50:58providing more insights into it
51:01really also working on the
51:02standardization topics side for
51:05example and so and so and so forth. So
51:07it was really important for us not to
51:09just develop a
51:11another sensor for example that is maybe
51:13on the market already and
51:15nobody is trusting sensors anymore and
51:17so on. So we really wanted to make sure
51:19that we before we enter the market and
51:22make more scalability in terms of
51:24devices more devices. We really want to
51:26understand the topic and not only for
51:28the field where the volume is later on
51:30but for the lab for the testing for the
51:32field and also for the simulation. So
51:35for us scale means not only more devices
51:37but a robust method that is also
51:41reproducible and and stable in terms of
51:43quality
51:44and also consistent in the evaluation
51:47logic. So once again if you're speaking
51:50about different languages in terms of
51:53what is the measurement technology
51:56what is the output in terms of data, you
51:58really need to see that the logic of the
52:00evaluation of the data that you're
52:02gathering
52:03is the same across different devices in
52:06your portfolio.
52:07So um for us it's really turning the
52:11technically strong method into something
52:13that fits real engineering workflows for
52:15example. And
52:18yeah maybe also talking about different
52:20markets and use cases. We also speak
52:23about with simulation companies for
52:26example because they also some gaps with
52:29missing real data in the gearbox. So
52:32everybody knows the glass front or glass
52:34covered gearboxes that are used as a
52:36foundation for simulation in the end but
52:40yeah you can you can easy easy it up or
52:42simplify this process by just putting
52:45real data into it. So this is why we
52:47really speaking from lab to field and
52:50simulation and not only in lubricants or
52:52oil. So last week we were there
52:54analytica or two weeks ago in Munich and
52:58we're even speaking about biotech use
53:00cases where air bubbles are
53:03are needed for example to to create some
53:06plants. So
53:08we really want to see what the effect of
53:11the air is not only in lubricants or oil
53:13but in different in different markets as
53:16well because either you want it or you
53:18want to don't want it. So if we are
53:21getting back to the example of the beer,
53:22you obviously want to have the foaming
53:25contrary to to the lubricant market. So
53:28the broader mission is really to move
53:30the topic of air from an invisible issue
53:33to something that is yeah more
53:34measurable, more discussable and also
53:37more extendable.
Wrap Up Pilots And Events
53:39Awesome. Well,
53:41um
53:42I think that's a great place to end it.
53:44You know I promised at the at the very
53:46at the very top of this
53:48this podcast that the viewers would
53:50leave with a better understanding and
53:52appreciation for air in oil and I
53:55certainly feel like I am leaving with a
53:57better appreciation for the subject. So
54:00hopefully the viewers are too because
54:02there's a hell of a lot more to it um
54:05than than meets the eye. So to both of
54:07you David and Lucas, really appreciate
54:10you coming to to discuss you know your
54:12your particular niche and the great
54:15contributions that you're making as
54:16well.
54:17I'm really excited actually to see the
54:19unit potentially in person a little bit
54:21later in the year and
54:25really appreciate your time.
54:27Thank you. Thank you for having having
54:29us. Maybe also to add this so where you
54:31can see it and how we can use it or to
54:32deploying it at the moment. So we are
54:34offering pilot measurements because you
54:36have obviously it's a new topic or not a
54:38new topic or but a different approach
54:41and we want to provide the possibility
54:43to just prove the value for each and
54:44every application. So
54:46we are offering the pilot measurements
54:48on one hand side and maybe you probably
54:51saw it on LinkedIn. We have a very cool
54:54demonstrator that we are using in our
54:56exhibitions and conferences. So the next
54:59one will be dry test where we also
55:00showcase the combination of real
55:03measurement data with simulation. So you
55:06can stay
55:07tuned on this as well and on the
55:09lubricant expo in Dusseldorf where you
55:10will be also as an exhibitor and
55:13surprisingly we have
55:15the the booth contrary to the to your
55:17booth. So hopefully you will have a lot
55:19of guys that want to visit you in
55:21Germany. Yeah, that that sounds that
55:24sounds good. I'll make sure to put
55:25details for you guys in the description
55:28below and so if anyone wants to to reach
55:31out you can reach out that way.
55:34All right, thanks gents. Really
55:35appreciate it.