Cooling Fan Tech

[AgitatedPancake]

The context of that example seems less relevant to the current discussion than it could be. The thinner core would absolutely flow 1000cfm of air easier than the thick core. But I think the question most guys here are posing is more like this:

You have a 12" thick radiator and 2" thick radiator, both with inlet temperatures of 50* and you flow 1000cfm through each of them. Which will have the highest outlet temperatures (extract the most heat from the system)?

If the 12" thick radiator extracts more heat than the 2" thick radiator for a given airflow, then the next question to pose is why do you feel like your example customer had overheating problems with a thick two core radiator that were solved by going to a single core. Did the increase in static pressure surpass the efficient zone of your fans, decreasing the available CFM of air to do work?

When it comes to the packaging constraints of the offroad world that these guys bring up, If your answers to the above are what I would expect, it seems that you may not be in disagreement that a thicker core radiator with a fan that can operate efficiently at higher static pressures may provide the most heat extraction per available packaging area in the chassis. Albeit with a penalty in operating efficiency of the fans

 

[DeltaPAGJohn]

Face value, 2".

My turn for a loaded question. Are the radiators the same volume, same frontal area, or same internal surface area?

Edit: added same surface area

Oh, right, yes both radiators have the same surface area, same construction, fins, tube space ect, so the 12" thick radiator will have a much larger internal surface area

So both radiator are moving 1000 CFM, both radiator have 50f inlet air temp and 100f outlet air temp, both radiators have dissipated the same amount of heat. Do you need more energy to move 1000CFM through the 12" radiator vs the 2" thick radiator?

 

[Will Scarlet]

Hey Will, Its fine, We have plenty of race teams and high performance clients that test and use our cooling systems in some of the most demanding applications. Probably more demanding than what most of the readers here will ever experience. Our technology has been proven in CAD/CFD modeling, then prototype "lab" tested & then empirically testing. Just like very tech. Below is a beautiful corvette that uses our cooling system for many years. It runs an 872 CID nitrous motor. This runs dual Delta PAG 16" brushless fans and our radiator. The first radiator we made used dual 1.25 tubes. The latest radiator it's running Delta PAGs new Mono-Core radiator. Same exact size, same exact setup just thinner core. Thinner, lighter & Cools better. More and more teams are adopting our technology and we're getting data in every day that's confirming our computer simulations. Its just legacy products/ways have been out for such a long time... its going to take time.

The way I see it, its been done wrong for such a long time, some people will understand or reluctantly try and eventually switch over. Then there are some people, so set in their ways, will go to their death bed thinking the earth is flat. Its OK, these things take time.

The problem here is you're not really providing any data and the comparison is with two systems that you designed. You say it cools better, but no data to backup that statement. I will say if the data supports it, it shows that you have improved your design but it's still not a comparison between convention design and your design.

Even considering that you mention replacing your old system with the newly designed system for the Corvette, you give no data for comparison and you don't state if there were any other cooling improvements made for the engine. You don't give anything showing where it improved. No temperature data period, no fan data period, and no cooling system data period. Just nothing.

Show is a real comparison between a conventional design and your design with the data to back it up. It's really time to put up or shut up.

Food for thought: And don't take this the wrong way, but how do you expect people to believe you when you we only have your word that it works?

 

[EndlessMtnFab]

But why are some people getting so hung up on motor efficiency? Nothing about our vehicles is efficient. Most of us would say .... "okay ... need more alternator to power that thing."


It seems like the general scope of this discussion keeps wavering around. Coolant Fan tech because Radiator Core tech. What's next ... Which Coolant Tastes best?

Seems like John is trying to deflect around.

 

[DeltaPAGJohn]

The context of that example seems less relevant to the current discussion than it could be. The thinner core would absolutely flow 1000cfm of air easier than the thick core. But I think the question most guys here are posing is more like this:

You have a 12" thick radiator and 2" thick radiator, both with inlet temperatures of 50* and you flow 1000cfm through each of them. Which will have the highest outlet temperatures (extract the most heat from the system)?

If the 12" thick radiator extracts more heat than the 2" thick radiator for a given airflow, then the next question to pose is why do you feel like your example customer had overheating problems with a thick two core radiator that were solved by going to a single core. Did the increase in static pressure surpass the efficient zone of your fans, decreasing the available CFM of air to do work?

When it comes to the packaging constraints of the offroad world that these guys bring up, If your answers to the above are what I would expect, it seems that you may not be in disagreement that a thicker core radiator with a fan that can operate efficiently at higher static pressures may provide the most heat extraction per available packaging area in the chassis. Albeit with a penalty in operating efficiency of the fans

Please take it step by step. Please dont add offroading or package constraints ect. We are only in a universe with two radiators, one is 12" thick the other is 2" thick. We can start added variables and hypothesize the results once we are all on the same page on the fundamentals.

Is it possible for a 12" thick radiator to have the same inlet and outlet cooling air temp as a 2" thick radiator?

 

[Treefrog]

Oh, right, yes both radiators have the same surface area, same construction, fins, tube space ect, so the 12" thick radiator will have a much larger internal surface area

So both radiator are moving 1000 CFM, both radiator have 50f inlet air temp and 100f outlet air temp, both radiators have dissipated the same amount of heat. Do you need more energy to move 1000CFM through the 12" radiator vs the 2" thick radiator?

12" will take more power. But as already stated:

If the radiators are of similar construction then you can not set the inlet and outlet air temps and CFM the same.
You can set the inlet and outlet air temps the same if the radiators are of different design.
Your question is broken.

If you have two radiators of the same frontal area, and the same power dissipation, the thicker one will have less restriction.

 

[DeltaPAGJohn]

The problem here is you're not really providing any data and the comparison is with two systems that you designed. You say it cools better, but no data to backup that statement. I will say if the data supports it, it shows that you have improved your design but it's still not a comparison between convention design and your design.

Even considering that you mention replacing your old system with the newly designed system for the Corvette, you give no data for comparison and you don't state if there were any other cooling improvements made for the engine. You don't give anything showing where it improved. No temperature data period, no fan data period, and no cooling system data period. Just nothing.

Show is a real comparison between a conventional design and your design with the data to back it up. It's really time to put up or shut up.

Food for thought: And don't take this the wrong way, but how do you expect people to believe you when you we only have your word that it works?

Well, the driver told me it was much better. Details traveling at 60mph staying below 160f, even hitting 140f, telling me that too cool now and needs to variable speed the pump. In city driving, traffic low speed, fans on, he would regularly see temps +200, never saw above 190, 180-185 normal with Mono-Core. He's running again in Florida in a month during Sick Week. Will get more info then. The show organizer has also converted to our Mono-Core. But there's is a big change for Sic2.0 that's making me nervous. Radiator is about half the size, but there's other benefits, and other detriments.

By the way the above, that is how empirical data looks like. Primarily a conversation with the driver.

 

[AgitatedPancake]

Please take it step by step. Please dont add offroading or package constraints ect. We are only in a universe with two radiators, one is 12" thick the other is 2" thick. We can start added variables and hypothesize the results once we are all on the same page on the fundamentals.

Is it possible for a 12" thick radiator to have the same inlet and outlet cooling air temp as a 2" thick radiator?

I mean technically, if the air is moving slow enough to completely saturate with heat by the time it exits, the answer would be yes right? Though that technicality probably isn't what ya meant.

We can take my questions step by step as well though just to make sure I get what you're saying, I'm here to learn. So the first part I asked to help refine my own understanding was:

You have a 12" thick radiator and 2" thick radiator, both with inlet temperatures of 50* and you flow 1000cfm through each of them (IF 1000cfm could be pulled through the 12" core). Which will have the highest outlet temperatures (extract the most heat from the system)?

 

[DeltaPAGJohn]

12" will take more power. But as already stated:


If you have two radiators of the same frontal area, and the same power dissipation, the thicker one will have less restriction.

What if the 12" radiator has more restriction, the internal construction is identical, but just thicker. inlet air 50f outlet air 100f both 1000 CFM

Is that possible?

 

[Treefrog]

What if the 12" radiator has more restriction, the internal construction is identical, but just thicker. inlet air 50f outlet air 100f both 1000 CFM

Is that possible?

Technically. If the fluid is 100f and the radiators have restriction to the point that all cooling is done within the first 2 inches.

 

[DeltaPAGJohn]

I mean technically, if the air is moving slow enough to completely saturate with heat by the time it exits, the answer would be yes right? Though that technicality probably isn't what ya meant.

We can take my questions step by step as well though just to make sure I get what you're saying, I'm here to learn. So the first part I asked to help refine my own understanding was:

You have a 12" thick radiator and 2" thick radiator, both with inlet temperatures of 50* and you flow 1000cfm through each of them (IF 1000cfm could be pulled through the 12" core). Which will have the highest outlet temperatures (extract the most heat from the system)?

Yes, that is what I ment. Heat saturation of the cooling air is exactly what I'm saying.

Is it possible to have the outlet air temp the same? Yes

 

[Will Scarlet]

Well, the driver told me it was much better. Details traveling at 60mph staying below 160f, even hitting 140f, telling me that too cool now and needs to variable speed the pump. In city driving, traffic low speed, fans on, he would regularly see temps +200, never saw above 190, 180-185 normal with Mono-Core. He's running again in Florida in a month during Sick Week. Will get more info then. The show organizer has also converted to our Mono-Core. But there's is a big change for Sic2.0 that's making me nervous. Radiator is about half the size, but there's other benefits, and other detriments.

By the way the above, that is how empirical data looks like. Primarily a conversation with the driver.

I understand what empirical data looks like, but this is the first time you have given any data like this. To me it's better than nothing and it's a start.

 

[DeltaPAGJohn]

Technically. If the fluid is 100f and the radiators have restriction to the point that all cooling is done within the first 2 inches.

Exactly! beautiful. So in this example at 1000CFM of air you reach full temp saturation at 2". But even though the two system are dissipating the same heat. they need very different fans to do so, right?

 

[JMRobins]

It seems like real-world situations are missing here. A thin radiator usually takes less power to flow a certain amount of air. If you can design a system to use a single row efficiently, that's great. In the real world, many of us have size constraints on radiator sizes. That leaves us with needing to go thicker on the core to get better cooling. That's where your fan won't do as good. It's clear to me that you engineered your fan for your radiator designs. I'm sure it works as you designed. However, in the real world, a single-row radiator that has enough size to dissipate enough heat might not fit. So a thicker radiator and a higher pressure fan is in order.

I don't doubt your fan/radiators work great for what they are designed for. but I doubt that your designs will work for many of our size constraints.

On another note, if you want to learn a ton about radiator design and efficiency, look into home-built airplane forums. There are some seriously talented and seasoned engineers with exceptional knowledge on this. In their case, they need the lightest and most efficient radiator design in heat dissipation, weight, and induced drag.

Disclaimer: I'm not an engineer and don't know much about radiator design, but I read a lot about it and forget most of it.

 

[Treefrog]

Exactly! beautiful. So in this example at 1000CFM of air you reach full temp saturation at 2". But even though the two system are dissipating the same heat. they need very different fans to do so, right?

Right.

But you just completely glossed over the low fluid temp and the highly restricted radiator. You are trying to compare a red painted orange to an apple.

If I bump the temp of to a more normal 200 degrees, the 2" will not dissipate the same amount of power. It's exit temp may only be 120, compared to the 12" being at 200.

 

[DeltaPAGJohn]

Right.

But you just completely glossed over the low fluid temp and the highly restricted radiator. You are trying to compare a red painted orange to an apple.

If I bump the temp of to a more normal 200 degrees, the 2" will not dissipate the same amount of power. It's exit temp may only be 120, compared to the 12" being at 200.

Please take it step by step. I am not glossing over anything, Im just lay out simply understood principals. We can apply your 200f temp later, but it wont matter at that point. You'll see.

Back to the original setup:

This example at 1000CFM of air you reach full temp saturation (100f) at 2". But even though the two system are dissipating the same heat. they need very different fans to do so. The 12" thick radiator will require a more powerful fan to get the same 1000CFM as the 2" radiator, right? What will happen if we put the same, more powerful fan on the 2" thick radiator?

 

[Treefrog]

Please take it step by step. I am not glossing over anything, Im just lay out simply understood principals. We can apply your 200f temp later, but it wont matter at that point. You'll see.

Back to the original setup:

This example at 1000CFM of air you reach full temp saturation (100f) at 2". But even though the two system are dissipating the same heat. they need very different fans to do so. The 12" thick radiator will require a more powerful fan to get the same 1000CFM as the 2" radiator, right? What will happen if we put the same, more powerful fan on the 2" thick radiator?

It would likely move more than 1000cfm.

But you still seem to dodge the issue of you are optimizing the radiator design to the thinner radiator and then applying the same design to a thicker radiator. Instead of optimizing both radiators.

So tell me, if both radiators are optimized internally such that exit temp is reached at the exit, which one take less power to move the air?

 

[DeltaPAGJohn]

It would likely move more than 1000cfm.

But you still seem to dodge the issue of you are optimizing the radiator design to the thinner radiator and then applying the same design to a thicker radiator. Instead of optimizing both radiators.

So tell me, if both radiators are optimized internally such that exit temp is reached at the exit, which one take less power to move the air?

By change construction, you're adding new variables. Now the difference is not only the thickness, you've changed a bunch of other variable. Lets keep both radiators the same and only difference is thickness. Actually most radiator companies keep the same FPI and tube spacing and just use more/wider tubes.

Back to the original example. So how much more air will you have going through the 2" system? Please recall, one radiator is 2" and the other is 12", 6x greater thickness? is it 6x more air or is it more?

Look, Im tired, its more that 6x its closer to 36x because of the velocity squared law, so its exponential. That's why airflow drops drastically in the fan curves when increase even a small amount of restriction. It has nothing to do with the type of fan, its just physics. Believe me don't believe me, i don't care.

Now add heat transfer coefficient (or rate of heat transfer) this stays linear based in Delta T. So the rate of heat transfer is dropping as air travels through the core. So the highest rate of heat transfer is in the beginning of the core, and if you make it thinner your quadrupling the volume of air while only losing a linear and diminishing rate of heat transfer. Hot Dog! You just evacuated a ton more heat by making it thinner! Hallelujah! Holy Shit! Where's the Tylenol!

 

[chaplinfj60]

why cant we just get a simple real word test set up. take a standard RAD of 26x19, or what ever is close. because that will fit most of our applications here, either in front or the rear of the vehicle and do some sort of test. where we are comparing apples to apples at least in packaging aspect. because i feel like that is where we need to see data.

something like a griffin rad with spal fan and PAGs set up that fits the same space. and come up with a few data points.

maybe someone all ready mentioned this and i missed it.

 

[CarterKraft]

why cant we just get a simple real word test set up. take a standard RAD of 26x19, or what ever is close. because that will fit most of our applications here, either in front or the rear of the vehicle and do some sort of test. where we are comparing apples to apples at least in packaging aspect. because i feel like that is where we need to see data.

something like a griffin rad with spal fan and PAGs set up that fits the same space. and come up with a few data points.

maybe someone all ready mentioned this and i missed it.

That is the only thing even worth discussing IMO.

I don't blame PAG at all for playing along, but if we were brilliant engineers we might have our OWN PAG and be building cooling systems...
This back and forth is pretty useless.

 

[DeltaPAGJohn]

This back and forth is pretty useless.

Agreed, I'm never going to get those hours back.

I don't blame PAG at all for playing along, but if we were brilliant engineers we might have our OWN PAG and be building cooling systems...

Aww, are you calling me a brilliant engineer? gosh 🥰

I think you're mistaking brilliance with my simple lack of fear of calling everyone else stupid. Of course there's a ton of research backing it and i'm lucky to work with some ridiculously impressive race teams that never say no to my hairbrained schemes.

 

[EndlessMtnFab]

If I can't blind them with brilliance, I will baffle them with my bullshit

Sorry John ..... Had to do that one.

 

[WaterH]

I don't know about Hydrodynamic:
-either he doesn't understand fluid dynamics, ironic considering his name
-or has drank too much of Spals cool-aid and doesnt want to hear anything else
-or has some vested interest in Spal products (sells spals products), or all the above.
Frankly, I don't care and I'm just going to ignore him and answer people that have a genuine questions.

Regarding Spal, I thing Spal made a product as best they can tip towing around everyone patents due to being late to the game. Their product is primarily good at very high pressures and as a result very inefficient. Saying you need to make your heat exchanger high pressure to justify the use of the Spal fan and Spal's brushless existence is silly. Please note most, if not all OEMs have core thicknesses of 1" or less.

Regarding "reputation", physics doesn't give a shit about reputation. This is not a high school cafeteria, its engineering.

I’m not aware of Hydrodynamic’s connection with Spal, but I won’t rule it out.

One thing I do know about is patents. A lot of people don’t realize you can get a patent on almost anything. A patent is worthless until you enforce it in court. That is where most patents get dropped.

True story, a woman in Panama City patented ceramic fish. I’m not talking about one artists interpretation of a fish. She thought she held the rights to every piece of pottery shaped like a fish. If you read the patent she filed, it sounded like she was right. My wife had a pottery shop in Panama City and sold some fish. This patent holder sued my wife in federal court. The case should have been thrown out immediately , but the judge heard the case because he wanted to write “case law”. The end of the story is my wife won the case without an attorney. (The woman had two)

Have you enforced any of your patents?

“Saying you need to make your heat exchanger high pressure to justify the use of the Spal fan and Spal's brushless existence is silly.”

This statement I find very courious. You realize I can flip it to “Saying you need to make your exchanger less resistance to justify the use of a PAG fan is silly”

Every time I have bought a E-fan, I allready had my exchangers. So it sounds like you are saying “then you can’t use our fans”.

Thats fine, just state that up front. Before I was asking people to verify your amp draw claims. Now I think the more likly thing to verify is your cfm claims. I suppose they need to be verified with a restriction. I guess, to be fair, I should have compared the Spal fans with a restriction also.

 

[Bebop]

but if we were brilliant engineers we might have our OWN PAG and be building cooling systems...

This is dumb.

 

[Outahand]

Back to the original example. So how much more air will you have going through the 2" system? Please recall, one radiator is 2" and the other is 12", 6x greater thickness? is it 6x more air or is it more?

I think I am following but I am confused here. The air flow was the same in your example. What do you mean by "how much more air will you have going through the 2" system?"

It takes 6x (or 36x?) pressure to move the same amount of air through the 12" core. But the heat is only dissipated in the first 2". So if you have a 2" core the same amount of air removes the same amount of heat but it can be pulled through the thinner core much easier.

Am I on the right track here?

 

[CarterKraft]

Agreed, I'm never going to get those hours back.

Aww, are you calling me a brilliant engineer? gosh 🥰

I think you're mistaking brilliance with my simple lack of fear of calling everyone else stupid. Of course there's a ton of research backing it and i'm lucky to work with some ridiculously impressive race teams that never say no to my hairbrained schemes.

If you are you are, no point not recognizing the facts, I really think it remains to be seen for anointing but the opportunity exists.

This is dumb.

Sure it might be, this is just I operate, If we were standing around PAG's race car or yours I wouldn't call you dumb if I didn't agree with you.
I have been humbled too many times in this business, realizing where I am wrong and learning what I didn't know is the key to getting smarter.

I have no problem explaining what I have experienced, tested, measured etc. but just because you have different results from your tests doesn't make you or I dumb, we need to learn why there is a difference.

 

[Bebop]

If you are you are, no point not recognizing the facts, I really think it remains to be seen for anointing but the opportunity exists.




Sure it might be, this is just I operate, If we were standing around PAG's race car or yours I wouldn't call you dumb if I didn't agree with you.
I have been humbled too many times in this business, realizing where I am wrong and learning what I didn't know is the key to getting smarter.

I have no problem explaining what I have experienced, tested, measured etc. but just because you have different results from your tests doesn't make you or I dumb, we need to learn why there is a difference.

You're missing my point which was answering this statement:

if we were brilliant engineers we might have our OWN PAG and be building cooling systems...

You can be a brilliant thermodynamics engineer and have no interest in building cooling systems.

 

[DeltaPAGJohn]

I think I am following but I am confused here. The air flow was the same in your example. What do you mean by "how much more air will you have going through the 2" system?"

It takes 6x (or 36x?) pressure to move the same amount of air through the 12" core. But the heat is only dissipated in the first 2". So if you have a 2" core the same amount of air removes the same amount of heat but it can be pulled through the thinner core much easier.

Am I on the right track here?

Yes, close, but yes.

In this part of the questioning we are adding the amount of energy needed to move 1000cfm through each system. And then say, well if use the same energy in both 12" thick radiator and 2" thick radiator what will happen. Well you will have a lower deltaT on the 2" radiator, instead of 100f out it will be, lets say 80f out, but the volume of air will increase exponentially. So, when you multiply the volume of air with the albeit lower Dt, the increase in heat rejection is enormous. To figure this out it needs to modeled and run in a simulation.

if you really really stand back and look at this (forest). If you can take away the relationship between volume of air & restriction VS rate of heat dissipation and area... I will never have to say another word, your pupils will dilate and you can never unsee this.

 

[Bebop]

In this part of the questioning we are adding the amount of energy needed to move 1000cfm through each system. And then say, well if use the same energy in both 12" thick radiator and 2" thick radiator what will happen.

Why would you?

Just use more energy to move more air through the 12" thick one.

 

[DeltaPAGJohn]

I’m not aware of Hydrodynamic’s connection with Spal, but I won’t rule it out.

One thing I do know about is patents. A lot of people don’t realize you can get a patent on almost anything. A patent is worthless until you enforce it in court. That is where most patents get dropped.

True story, a woman in Panama City patented ceramic fish. I’m not talking about one artists interpretation of a fish. She thought she held the rights to every piece of pottery shaped like a fish. If you read the patent she filed, it sounded like she was right. My wife had a pottery shop in Panama City and sold some fish. This patent holder sued my wife in federal court. The case should have been thrown out immediately , but the judge heard the case because he wanted to write “case law”. The end of the story is my wife won the case without an attorney. (The woman had two)

Have you enforced any of your patents?

The only people saying that patents are silly are the ones holding all the patents, yeah they definitely don't want you getting a patent. There are primarily two types of patents a design patent (you own that exact look) and a utility patent (you own that science, no matter how it looks). A utility patent is much harder to get.

In your example; There is nothing innovative about ceramics, there's nothing innovative about a fish shape. Yes, you can get a patent that says you own a ceramic fish that is exactly 12" long with a tail that's 4" wide. Yes, that's yours and nobody can do that. So someone make a fish that is 12.01" long and has a tail that is 3.97" tall. It does not infringe.

I don't care for design patents but have several of both. Design patents imo are trademarks and you need them for branding and corp. bs. I dont know, my lawyers tell me who to give money to. Yes, I've enforced them and have done very well. I live in NYC, we got plenty of good lawyers here foaming at the mouth.