Oil Filter Pressure Differential testing (PSID)

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Some bench racers' have "theories" that match the real data, but some have also seen similar data in other sources and read a lot of papers/studies, and also have engineering backgroungs. So it's easy to see who's a bench racer or not. ;)

Member @Ascent Filtration Testing here, who owns a test lab and does ISO 4548 testing, has also shown some really good testing data. Something you would hardly ever see at that level from any filter manufacturer.
 

ZeeOSix

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When someone doesn't understand something like basic physics, and someone who does explains why they don't see things correctly, then they typically get all butt hurt and think they are being "bullied". Instead, maybe they should try to learn something and do some self study of the subjuct matter before trying to argue and defend their misconceptions. That's why technical discussions go around and around and turn into "bickering". Maybe BITOG should say no more technical discussions and only talk about the weather ... but then someone would claim the sky is green and it would start again, lol.

BITOG is a place where people can get very technical when misconceptons in discussions keep popping up - people can sometimes get challenged for making claims that aren't valid. And sometimes people have a misconception that's so burned into their brain that no amount of evidence will turn on the light bulb. Nothing worse than spreading misconceptions.
 
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Here is a summery of the data. You guys have waited long enough, and a video is not possible at the moment.

Capacity Compairson Graph Pic 1.jpg
Efficiency Compairson Graph Pic 2.jpg
Efficiency Compairson Graph Pic 3.jpg






Efficiency Compairson Graph Pic 4.jpg
 

ZeeOSix

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Zee - I had not intended to include you in the masses; if you took offense then I apologize. But I stand my ground; there are too many "hit and run" comments made here about filters and filtration effects with little to no data to back them up.
No offense taken. I try to post data and links to studies, etc that backup what I claim when the discussion gets in depth. Unlike many here that can't or wont backup their claims even if they are asked to. Just because people don't setup and run their own experiments doesn't mean they don't know what's going on. And even if a home experiment is done (Project Farm action), the whole test methodology, procedure and data collection/analysis can certainly be scrutinized too.
 
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When someone doesn't understand basic fluid dynanics, and someone who does explains why they don't see things correctly, then they typically get all butt hurt and think they are being "bullied". Instead, maybe they should try to learn something and do some self study of the subjuct matter before trying to argue and defend their misconceptions. That's why technical discussions go around and around and turn into "bickering". Maybe BITOG should say no more technical discussions and only talk about the weather, lol.

BITOG is a place where people can get very technical when misconceptons in discussions keep popping up - people get challenged for making claims that arent valid. And sometimes people have a misconception that's so burned into their brain that no amount of evidence will turn on the light bulb. Nothing worse than spreading misconceptions.
I explained it very well. Don’t talk about me, focus. Yes, or no, every can oil filter like in the picture has an outlet pipe? There are no mystery areas the gauge enters. I don’t mind learning, but you don’t teach. If you make it about what I know again as your explanation, forget it.
 

ZeeOSix

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I explained it very well. Don’t talk about me, focus. Yes, or no, every can oil filter like in the picture has an outlet pipe? There are no mystery areas the gauge enters. I don’t mind learning, but you don’t teach. If you make it about what I know again as your explanation, forget it.
Look at where the pressure sensors are located. That's a special filter mount that has built-in pressure sensing ports as close to the filter inlet and outlet as possible - I already said that in a previous post. The sensors do sense the inlet and outlet pressure as close to the filter as possible, and therefore certainly are measuring the filter assembly delta-p (Ch1 minus Ch2).

Every lab that does ISO filter testing uses a similar filter mount. I'm sure @Ascent Filtration Testing can chime in and tell you about it too.
 
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Look at where the pressure sensors are located. That's a special filter mount that has built-in pressure sensing ports as close to the filter inlet and outlet as possible - I already said that in a previous post. The sensors do sense the inlet and outlet pressure as close to the filter as possible, and therefore certainly are measuring the filter assembly delta-p (Ch1 minus Ch2).

Every lab that does ISO filter testing uses a similar filter mount. I'm sure @Ascent Filtration Testing can chime in and tell you about it too.
The delta p occurs where? On the inner side of the filter media, across the media. It is a large chamber the oil enters, the center tube. After that the oil enters the outlet stub and the psi is determined by the pipe size. There is no pressure sensor on the inside of the center tube before the outlet pipe. With constant flow, psi varies accordingly at each interface. I cannot see how the delta p is measured this way.
Look at where the pressure sensors are located. That's a special filter mount that has built-in pressure sensing ports as close to the filter inlet and outlet as possible - I already said that in a previous post. The sensors do sense the inlet and outlet pressure as close to the filter as possible, and therefore certainly are measuring the filter assembly delta-p (Ch1 minus Ch2).

Every lab that does ISO filter testing uses a similar filter mount. I'm sure @Ascent Filtration Testing can chime in and tell you about it too.
it’s no use, not answering my question,. The pressure drop occurs at the media, which are holes like any other cross section, then the oil goes through the outlet nipple, where that cross section determines the new pressure. Restriction change doesn’t reduce flow. It’s really just the definition of psi units, nothing complicated. All done, go buy the Ultras and be happy.
 

ZeeOSix

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^^^ You'll never get it ... and this is becoming a waste of time since you won't listen to logic. Fact is the special mount that the filter is mounted to measures the oil pressure right where the oil enters the base plate, and also very clost to where the oil leaves the filter. If there is a 1/4-1/2" of distance from the base plate outlet hole there isn't going to be any kind of measurable difference compared to if it was the pressure up inside the center tube. The pressure sensors are not in any of the external tubing going into or out of the filter mount.

If you heard the same thing from @Ascent Filtration Testing would you believe it?
 

ZeeOSix

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@Ascent Filtration Testing ... care to share your filter delta-p measuring setup? Some may say you did it wrong and weren't really measuring the delta-p across the oil filter, so curious on what your setup is. ;) 😄

capacity-compairson-graph-pic-1-jpg.59363
 
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@Ascent Filtration Testing ... care to share your filter delta-p measuring setup? Some may say you did it wrong and weren't really measuring the delta-p across the oil filter. ;) 😄


capacity-compairson-graph-pic-1-jpg.59363

@Ascent Filtration Testing ... care to share your filter delta-p measuring setup? Some may say you did it wrong and weren't really measuring the delta-p across the oil filter, so curious on what your setup is. ;) 😄

@Ascent Filtration Testing ... care to share your filter delta-p measuring setup? Some may say you did it wrong and weren't really measuring the delta-p across the oil filter, so curious on what your setup is. ;) 😄

capacity-compairson-graph-pic-1-jpg.59363
I think you can see the pressure taps in the video. To be honest it does not mater if people say I did something wrong. I have spent many years running filter tests, designing, and building test rigs, and work with the committees that write the standards. My peers know better.
 

ZeeOSix

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I think you can see the pressure taps in the video. To be honest it does not mater if people say I did something wrong. I have spent many years running filter tests, designing, and building test rigs, and work with the committees that write the standards. My peers know better.
I know ... but seems there is some disbelief that a setup like the one in this thread that's being discussed, or what you'd use in the lab which is probably very similar, isn't truly giving the delta-p across an oil filter assembly. It isn't rocket science, but seems that way when these discussions go off in the weeds. 😄
 
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I know ... but seems there is some disbelief that a setup like the one in this thread that's being discussed, or what you'd use in the lab which is probably very similar, isn't truely giving the delta-p across an oil filter assembly.
Well for the lab tests there is a standard for where the pressure taps are located, and I don't recall the exact measurements/requirements, it something like within 5 or 10 times the tube ID from the filter inlet and outlet, but you want them close to the inlet and outlet. If a client sends me a filter head and it has pressure taps and they want me to use them I do. As long as your transducer is calibrated, it is an accurate measurement.
I will not participate in any disputes though.
 

ZeeOSix

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Well for the lab tests there is a standard for where the pressure taps are located, and I don't recall the exact measurements/requirements, it something like within 5 or 10 times the tube ID from the filter inlet and outlet, but you want them close to the inlet and outlet. If a client sends me a filter head and it has pressure taps and they want me to use them I do. As long as your transducer is calibrated, it is an accurate measurement.
I will not participate in any disputes though.
Figured as much ... thanks for the info. This pressure measuring stuff is pretty simple, so there shouldn't really be any disputes to start with ... ;) :)
 
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I think you can see the pressure taps in the video. To be honest it does not mater if people say I did something wrong. I have spent many years running filter tests, designing, and building test rigs, and work with the committees that write the standards. My peers know better.
I don’t know anyone here saying you did it wrong. Hope you feel better is the main thing. That sounded rough. We take air and the lungs for granted. Great testing to ponder, marketing free results.
 

ZeeOSix

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Someone here is claiming the OPs setup in this thread isn't measuring the delta-p across the filter (Ch1 minus Ch2). So if testing standards like Andrew has mentioned that dictate the IN and OUT pressure sensors can be up to 10 tube diameters away from the filter, and that gives good pressure reading results for an ISO test procedure, then so does the special filter mount where the pressure sensors are even closer to the filter.
 
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dnewton3

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Pounds per square inch varies according to the size of the "pipe" with the same flow rate. An oil filter has an inlet pipe and an outlet pipe.
No - there's no "inlet pipe" or "outlet pipe" in a filter. Pipes have flow loss and pressure loss (when flow is occurring; not applicable in static condition) when the walls of the pipes create drag related to frictional effects and resultant boundary layers inducing fluid shear, etc. Rough walls create more drag and dP; smooth walls less so. With short pipe lengths, these losses are so small that they are reasonably ignored. In really long pipe runs, it's very important to consider. However, there ain't no pipes in a filter, so your assertion means zilch.
Rather, filters have "holes" (or ports, if you prefer) which are the inlet and outlet routes. Those holes present a potential for dP, but ONLY if the holes are significantly smaller in area than the cross-sectional area of the supply line or exit line. Generally, the inlet/outlet holes in a filter are greater in total cross-sectional area than the supply/exit oil circuits themselves, so the "holes" are a moot topic here.

There is no other way in or out of an oil filter. I don't need a test setup to know this, it is not theory, it's very basic physics, units of measurement, math. Wrong?
No - you're not wrong regarding the entry/exit points. One way in and one way out. Did someone say otherwise?


Looking at the pictures, this is the general way I see how the set up controls lube flow ...
- oil flows via the inlet supply line as it goes into the filter mount
- oil touches the inlet pressure transducer which is mounted AFTER that supply line inlet, just ahead of the filter media
- oil flows through the media (or through the BP, if the dP across the media is too great and invokes the BP action)
- oil touches the outlet pressure transducer which is mounted BEFORE the outlet line (mirror to the inlet in concept)
- oil flows via the outlet line as it heads to the engine

There's no "pipe" causing any significant restriction here. The transducers are a close as can be practically placed, and exist mere millimeters ahead and behind of the oil's path through the media. Even if the filter goes into BP mode, that does not affect the dP reading across the two transducers because, as you state, there's only one way in and one way out. If and only if the "holes" of the filter were significantly restrictive relative to the overall capability of the system, then you could claim that the "holes" contribute to the dP. But that's not how oil filters are designed/made. The several inlet holes in the baseplate represent enough cross-sectional area in total, as does the outlet as well, that the total flow through the filter is not inhibited by the "holes" relative to the engine's other restrictive points.

If you want to acknowledge pipes in the system, I'll mention these ...
- there's the suction pipe coming from the oil-pickup and connecting to the oil pump is typically the smallest "pipe" in terms of cross-sectional area in just about any typical engine lube system. The flow via that pipe is pretty large, because the PD pumps always end up bleeding off pressure via their PRV to protect the entire system from over-pressurization. So the flow capability of the tube has to supply both what is used in the engine and what is dumped back to the sump
- We could consider the engine's oil galleys as "pipes", because they are the flow routes through the engine that have cross-sectional area and also have walls.
- Some engines have small oil-jet cooling pipes under the pistons, but obviously not all engines
- Some engines have oil carried externally (or internally) via pipes to things like turbo chargers for bearings, etc; not all engines, obviously
None of that matters to this experiment that RSMike ran, though. He measured the dP as close as practical to the media as he can, and the "holes" in the filter are not the restriction you imply.


Why? I don't mind being wrong, and don't need to be right.
People leave a discussion as it devolves into personal attack bickering, which is bullying. Because of someone needing to "win", when it's no longer about the science, and they are the wrong ones? No wonder some very good resources in people have chosen to leave this site. The bullying to "win" needs to stop. People should feel free to ask and ponder without being personally judged, that's good discussion. I guarantee you there are people here who think twice about asking something or challenging something because they know what is coming at them if they do. That's wrong.
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People leave for all manner of reasons; I accept that for what it is. People often confuse legit challenges to their opinions and theory with personal attacks. (Yet, no one here has called anyone else derogatory names, insulted family members, called into question one's genetic lineage, etc.) The quantity of people here whom are intimidated from asking questions are no less in count than those who are unafraid to spout off poorly reasoned garbage. It's an open forum, and as long as the rules are not broken, there's free exchange available to those who willingly participate.
 
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If anyone wants to learn about flows, cross sectional areas, friction/head-loss, pipe and fitting effects, velocities, and fluid dynamics in general. I would encourage one to look at these methods/equations:
1) Bernoulli's Principle and Equation
2) Darcy Weisbach and Hazen Williams
3) Continuity Equation and Reynolds Transport Theory

These are a great start for for understanding the physics, and empirical data involved for predicting fluid systems/models. Not to mention lots of fun to learn with many ahhhh, so that's how that works moments!
 
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No - there's no "inlet pipe" or "outlet pipe" in a filter. Pipes have flow loss and pressure loss (when flow is occurring; not applicable in static condition) when the walls of the pipes create drag related to frictional effects and resultant boundary layers inducing fluid shear, etc. Rough walls create more drag and dP; smooth walls less so. With short pipe lengths, these losses are so small that they are reasonably ignored. In really long pipe runs, it's very important to consider. However, there ain't no pipes in a filter, so your assertion means zilch.
Rather, filters have "holes" (or ports, if you prefer) which are the inlet and outlet routes. Those holes present a potential for dP, but ONLY if the holes are significantly smaller in area than the cross-sectional area of the supply line or exit line. Generally, the inlet/outlet holes in a filter are greater in total cross-sectional area than the supply/exit oil circuits themselves, so the "holes" are a moot topic here.


No - you're not wrong regarding the entry/exit points. One way in and one way out. Did someone say otherwise?


Looking at the pictures, this is the general way I see how the set up controls lube flow ...
- oil flows via the inlet supply line as it goes into the filter mount
- oil touches the inlet pressure transducer which is mounted AFTER that supply line inlet, just ahead of the filter media
- oil flows through the media (or through the BP, if the dP across the media is too great and invokes the BP action)
- oil touches the outlet pressure transducer which is mounted BEFORE the outlet line (mirror to the inlet in concept)
- oil flows via the outlet line as it heads to the engine

There's no "pipe" causing any significant restriction here. The transducers are a close as can be practically placed, and exist mere millimeters ahead and behind of the oil's path through the media. Even if the filter goes into BP mode, that does not affect the dP reading across the two transducers because, as you state, there's only one way in and one way out. If and only if the "holes" of the filter were significantly restrictive relative to the overall capability of the system, then you could claim that the "holes" contribute to the dP. But that's not how oil filters are designed/made. The several inlet holes in the baseplate represent enough cross-sectional area in total, as does the outlet as well, that the total flow through the filter is not inhibited by the "holes" relative to the engine's other restrictive points.

If you want to acknowledge pipes in the system, I'll mention these ...
- there's the suction pipe coming from the oil-pickup and connecting to the oil pump is typically the smallest "pipe" in terms of cross-sectional area in just about any typical engine lube system. The flow via that pipe is pretty large, because the PD pumps always end up bleeding off pressure via their PRV to protect the entire system from over-pressurization. So the flow capability of the tube has to supply both what is used in the engine and what is dumped back to the sump
- We could consider the engine's oil galleys as "pipes", because they are the flow routes through the engine that have cross-sectional area and also have walls.
- Some engines have small oil-jet cooling pipes under the pistons, but obviously not all engines
- Some engines have oil carried externally (or internally) via pipes to things like turbo chargers for bearings, etc; not all engines, obviously
None of that matters to this experiment that RSMike ran, though. He measured the dP as close as practical to the media as he can, and the "holes" in the filter are not the restriction you imply.



People leave for all manner of reasons; I accept that for what it is. People often confuse legit challenges to their opinions and theory with personal attacks. (Yet, no one here has called anyone else derogatory names, insulted family members, called into question one's genetic lineage, etc.) The quantity of people here whom are intimidated from asking questions are no less in count than those who are unafraid to spout off poorly reasoned garbage. It's an open forum, and as long as the rules are not broken, there's free exchange available to those who willingly participate.
There is a pipe coming into the filter base, seen as a hole, and a pipe leading out. That’s the one the filter screws onto. That’s just how it is.
People aren’t posting because they are confused, but because bullying is a real problem. I am not easily intimidated maybe others are more so. Anytime someone says like you said “your assertion means zilch” that’s off topic and bullying. it isn’t about me and my assertions, it’s about oil systems. It doesn’t effect me at all, but it does make the site less valuable to those who aren’t wanting to be put down. Try to say something not glowing about a Fram Ultra and watch what happens. Putting people down gets rid of their desire to talk and come back.
I didn’t see any explanation yet, but Ascent’s advice is good. Go back to the 17th century when they started learning about it, or earlier. I took a graduate course in hydraulics at UC Davis eons ago, but don’t remember one thing from it. I know I liked it and did well in it. The explanation should be given with good intentions regardless of the askers resume. No one here should feel lesser than others, or have to spout their resume. I also worked with a lot of professors at Stanford, and I remembered one telling me one can know a lot, (like he does,) but not everyone can explain it so others understand, like this other professor popular with undergrads.
I know the oil enters the filter through a pipe, hits the media which is a restriction, so the pressure increases to keep the flow going through the media. Then it goes into the center tube and out the threaded pipe, to it’s path back to the oil pan only to do it again. The pressure gauge is a dead end point along the way to measure pressures. That’s all I know. If one truly understands how it works with measuring dp at the inlet and outlet pipes, when dp occurs across the media, they should be able to put it in simple terms for a dummy like me to understand.
 
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