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The water pump is pretty interesting.

The charts don't mean as much to me, I don't know how much static pressure there is in a given setup.
 
DeltaPagJohn, Welcome to the party. I'm just catching up on this thread. It seems the wolves are pushing you into a corner.
That's fine, Now is the time to prove your product. The link to the product line is nice, thanks for that.
If you want the respect of the pack then we need you go full on egghead, geek, nerd mode. We LOVE tech. Like really in depth cause and effect. You may start us in airflow 101 class and some will argue but it will work out. We have been burned before by "flash in the pan " companies so we are naturally hesitant to quickly jump on board.
The Off Road community may not seem high tech from the outside but I can assure you it can hold it's own.
 
RustyC said:
DeltaPagJohn, Welcome to the party. I'm just catching up on this thread. It seems the wolves are pushing you into a corner.
That's fine, Now is the time to prove your product. The link to the product line is nice, thanks for that.
If you want the respect of the pack then we need you go full on egghead, geek, nerd mode. We LOVE tech. Like really in depth cause and effect. You may start us in airflow 101 class and some will argue but it will work out. We have been burned before by "flash in the pan " companies so we are naturally hesitant to quickly jump on board.
The Off Road community may not seem high tech from the outside but I can assure you it can hold it's own.
Click to expand...
Thank you for the welcome RustyC. Lets recap a bit, my intension was never to get deep into the weeds on this topic. I was attracted by a comment from another post (WalterH post# 95) noticing, empirically, that the Spal brushless are not very efficient. And I was like, "Yeah, well did you take a look at Delta PAG? They're far more efficient". Our clients complain about that all the time, probably why they're our clients.

That was like a year ago, came back to read comments saying Delta PAG fans don't move a ton of air with their thin blades and low profile motors and only amperage will determine how much air they move, ect. Nonsense. I ignored it for the most part. I kinda feel like when you get trapped debating a flat earther at the bar. So I mostly responded to the post inquiring who the hell is Delta PAG? Understandable, since Delta PAG does not advertise at all.

Now, my mistake, I did not notice the first post from hydrodynamic trying to sell his wears, so I guess I was stepping on his toes by chiming in on this thread. My apologies. But I feel its important to note that efficiency is very important and what he's showing is a very inefficient system.

In my attempt to explain how its possible one fan can move the same air at lower amps, i.e. efficiency. I pointed out one difference that is glaringly obvious, hub diameter. Now to touch on the other affect of hub diameter and that is core utilization. The size of the hub plays a huge roll on how air through the entire system (radiator included). You need to think about this holistically. In a cooling system, what's the point of the fan without the radiator and vis versa. If you take a look at your radiator core with a Flir camera you'll see that cooling happens primarily in the shape of a donut. This is very prominent with thin shrouds or no shrouds at all. If you have a large fan hub, a large portion of your radiator core is not doing any cooling. Here are some photos of CFD simulations and product shots. 3" hub vs 8" hub

Fan Hub.jpg
TECHNOLOGY_PAGE_image-4.jpg


Here's two more morsels of controversy; Two very common misconceptions is that paddle blades move more air and thicker radiators cool better. That's for another time
 
DeltaPAGJohn said:
Here's two more morsels of controversy; Two very common misconceptions is that paddle blades move more air and thicker radiators cool better. That's for another time
Click to expand...

Now is probably a good time. This is exactly what I was trying to say earlier. You just posted up some solid info on why the hub size matters (insert inappropriate joke of your choice here). I'd be curious for more info onthe blade count, curve, pitch, etc. :beer:
 
DeltaPAGJohn said:
Here's two more morsels of controversy; Two very common misconceptions is that paddle blades move more air and thicker radiators cool better. That's for another time
Click to expand...
If the only change you make to a cooling system is you go to a thicker core the net result will effectively be more cooling.

The volume will help a little to smooth over spikes in load and the extra area exposed to the moving air will result in more heat transfer from the coolant to the air, even if less efficient than a thinner core.
 
arse_sidewards said:
If the only change you make to a cooling system is you go to a thicker core the net result will effectively be more cooling.

The volume will help a little to smooth over spikes in load and the extra area exposed to the moving air will result in more heat transfer from the coolant to the air, even if less efficient than a thinner core.
Click to expand...

That's assuming the air flow goes unchanged. And the thicker core might slow down the air flow. Lotta variables on that one too. Are the cores staggered? Does your fan have enough strength to keep pulling air through at the same rate? Does the boogeyman check his closet for Chuck Norris?

I'll let PAG take over for that one .....
 
EndlessMtnFab said:
That's assuming the air flow goes unchanged. And the thicker core might slow down the air flow. Lotta variables on that one too. Are the cores staggered? Does your fan have enough strength to keep pulling air through at the same rate? Does the boogeyman check his closet for Chuck Norris?

I'll let PAG take over for that one .....
Click to expand...
I'm sure you could concoct some weird situation where it gets worse but for pretty much anyone with an automotive application taking your existing radiator and replacing it with one with a thicker core is gonna result in a better performing cooling system.

A thicker core WILL slow down airflow but it will more than make up for it by putting more heat into that air.
 
arse_sidewards said:
I'm sure you could concoct some weird situation where it gets worse but for pretty much anyone with an automotive application taking your existing radiator and replacing it with one with a thicker core is gonna result in a better performing cooling system.

A thicker core WILL slow down airflow but it will more than make up for it by putting more heat into that air.
Click to expand...
Agreed.

There's a lot of weirdos out there .... so weird situations are sure to follow. :laughing: Was just trying to clarify a potential blanket statement ... before some newly arrived google newb takes info as gospel.
 
EndlessMtnFab said:
That's assuming the air flow goes unchanged. And the thicker core might slow down the air flow. Lotta variables on that one too. Are the cores staggered? Does your fan have enough strength to keep pulling air through at the same rate? Does the boogeyman check his closet for Chuck Norris?

I'll let PAG take over for that one .....
Click to expand...
Yup, you hit the nail on the head. A thicker core will create higher static pressure, which will reduce velocity of air. To maintain the same velocity of air at higher static pressure, power consumption goes exponential. Similar to drag, energy needed to travel from 100mph to 200mph is not double, its quadruple. What you find is to have the same heat rejection rate as a thinner more efficient core, you'll need to spend double the power... for the same amount of cooling. Not to mention thickness and weight. Why? Cause marketing has taken over engineering.

Another important factor is cooling air heat saturation. As air is traveling through the core its picking up heat. Higher the Delta T (System temp - Ambient temp) the higher rate of heat transfer. So when air first enters the core, heat rejection is as its highest rate and drops as it goes through and picks up heat, so diminishing returns the thicker you get.

There is an optimal thickness and we build custom radiators with our Mono-Core design. Just one row.

It does get kinda complicated... ah not really. I think the real problem is, its been done wrong for such a long time people wont consider something else.
 
arse_sidewards said:
I'm sure you could concoct some weird situation where it gets worse but for pretty much anyone with an automotive application taking your existing radiator and replacing it with one with a thicker core is gonna result in a better performing cooling system.

A thicker core WILL slow down airflow but it will more than make up for it by putting more heat into that air.
Click to expand...

That’s what I was going to say. I’ve seen guys change to a thicker rad and had vastly better cooling more than once. Not sure of the science, but I know what I’ve seen work.

Question for Delta PAG, it all makes sense that a brushless motor would last longer and have less drag. But I don’t really see that brushes are that much drag. So the idea that your fan uses considerable less power to move the same air is a bit hard to believe.

I have Four 12” Spal brush fans on my project truck. The specs from Spal are 1381 cfm with a 30 amp fuse. (I could not find a running amp claim) I personally measured 22 amps on one running. Your site says your 12” brushless fan pulls 2100 cfm at 14 amps. Can you break down where that efficiencies are coming from? Example 30% from brushes, 30% from smaller hub and 30% from better fan design.
 
Outahand said:
One of my Buick buddies has a dual DeltaPAG fan on his 87 Grand National and is very pleased with it.

I have one on my 65 Vista Cruiser with an 87 Grand National turbo V6. I ended up not using the controller but it works well triggered by my ecm. Pulls a lot of air. I have not measured amp draw. It works way better than the stock GN fan I was using. It did not fix all but I have an intercooler shroud right behind it and I think I need to get air out of the engine compartment better.
Click to expand...

Outahand, could you possibly measure the amp draw? I don’t know you, but it doesn’t appear that you just joined to plug Delta, so it would go along way if your measurement was close to the Delta PAG web site claims.
 
WaterH said:
Outahand, could you possibly measure the amp draw? I don’t know you, but it doesn’t appear that you just joined to plug Delta, so it would go along way if your measurement was close to the Delta PAG web site claims.
Click to expand...
from 4 min
 
DeltaPAGJohn said:
But I feel its important to note that efficiency is very important and what he's showing is a very inefficient system.

In my attempt to explain how its possible one fan can move the same air at lower amps, i.e. efficiency. I pointed out one difference that is glaringly obvious, hub diameter. Now to touch on the other affect of hub diameter and that is core utilization. The size of the hub plays a huge roll on how air through the entire system (radiator included). You need to think about this holistically.
Click to expand...

DeltaPAGJohn said:
If you have a large fan hub, a large portion of your radiator core is not doing any cooling. Here are some photos of CFD simulations and product shots. 3" hub vs 8" hub

Fan Hub.jpg
Click to expand...
Assuming these are nominal 18" Fans
18" blade = 254 sq. in. surface area
3" hub =7 sq. in. surface area = 97% blade area
8" hub = 50 sq. in. surface area = 80% blade area
The PAG has 17% more blade but this area of the blade is not as useful as the outer area
The PAG blade would be turning at 1,965 surface feet per minute assuming 2500rpm rotor speed
The Spal blade would be turning at 5,240 surface feet per minute assuming 2500rpm rotor speed
The outer blade on both would be turning at 11,790 surface feet per minute assuming 2500rpm rotor speed
Hopefully this shows that the majority of the blade speed doing the work is on the outer blade. This is why modern blade designs have a deeper blade towards the middle to move more air and a thinner blade at the tips to move less so the load is more even across the blade.
The PAG has high pitch blades at the rotor but they can only be turned so much to compensate

blade-pitch.jpg
 
HYDRODYNAMIC said:
Assuming these are nominal 18" Fans
18" blade = 254 sq. in. surface area
3" hub =7 sq. in. surface area = 97% blade area
8" hub = 50 sq. in. surface area = 80% blade area
The PAG has 17% more blade but this area of the blade is not as useful as the outer area
The PAG blade would be turning at 1,965 surface feet per minute assuming 2500rpm rotor speed
The Spal blade would be turning at 5,240 surface feet per minute assuming 2500rpm rotor speed
The outer blade on both would be turning at 11,790 surface feet per minute assuming 2500rpm rotor speed
Hopefully this shows that the majority of the blade speed doing the work is on the outer blade. This is why modern blade designs have a deeper blade towards the middle to move more air and a thinner blade at the tips to move less so the load is more even across the blade.
The PAG has high pitch blades at the rotor but they can only be turned so much to compensate
Click to expand...

I think your math is wrong, Delta PAG has 21% more blade area for the 18". I'm not sure I understand what you mean by useful, the entire blade area is useful. A properly designed fan blade produces the same pressure drop from hub to tip. That's very important and kind of a standard model in CFD software (Computational Fluid Dynamics)

The way you do that, which you eluded to, is by adjusting 3 major factors of an airfoil; cord length, angle of attack and camber. Goal here is to even out the pressure from hub to tip at any give RPM. That's what this picture is. See how even the orange color is from hub to tip... that's sexy
CFD2.jpg
 
DeltaPAGJohn said:
A thicker core will create higher static pressure, which will reduce velocity of air. To maintain the same velocity of air at higher static pressure, power consumption goes exponential.
Click to expand...

DeltaPAGJohn said:
What you find is to have the same heat rejection rate as a thinner more efficient core, you'll need to spend double the power... for the same amount of cooling. Not to mention thickness and weight. Why? Cause marketing has taken over engineering.

There is an optimal thickness and we build custom radiators with our Mono-Core design. Just one row.

It does get kinda complicated... ah not really. I think the real problem is, its been done wrong for such a long time people wont consider something else.
Click to expand...
This is the fundamental part where your fan design is not efficient.

"You Keep Using That Word, I Do Not Think It Means What You Think It Means"

Efficient is not two fans instead of one, or a core with double the surface area to cool an application. Just to say yes my fans are energy efficient.
A thicker core with half the surface area and a single fan with enough power to pull the air to cool the application is efficient.
Triple 1" cores or dual 1.25" or bar and plate 2.5" cores are pretty common in 19" x 31" and larger when you start to have fun.
1200W of cooling fans turns into maybe 2HP even if its 10HP , I don't think anyone is going to say, hey maybe I should double my radiator footprint and double my fan count to save a couple HP.
 
DeltaPAGJohn said:
I think your math is wrong, Delta PAG has 21% more blade area for the 18". I'm not sure I understand what you mean by useful, the entire blade area is useful. A properly designed fan blade produces the same pressure drop from hub to tip. That's very important and kind of a standard model in CFD software (Computational Fluid Dynamics)

The way you do that, which you eluded to, is by adjusting 3 major factors of an airfoil; cord length, angle of attack and camber. Goal here is to even out the pressure from hub to tip at any give RPM. That's what this picture is. See how even the orange color is from hub to tip... that's sexy
CFD2.jpg
Click to expand...
Sorry I didn't calculate your extra 4%
I see your pressure is even from hub to tip except for the red on the outer edges but how much static pressure can that blade pull?
 
HYDRODYNAMIC said:
This is the fundamental part where your fan design is not efficient.

"You Keep Using That Word, I Do Not Think It Means What You Think It Means"

Efficient is not two fans instead of one, or a core with double the surface area to cool an application. Just to say yes my fans are energy efficient.
A thicker core with half the surface area and a single fan with enough power to pull the air to cool the application is efficient.
Triple 1" cores or dual 1.25" or bar and plate 2.5" cores are pretty common in 19" x 31" and larger when you start to have fun.
1200W of cooling fans turns into maybe 2HP even if its 10HP , I don't think anyone is going to say, hey maybe I should double my radiator footprint and double my fan count to save a couple HP.
Click to expand...
"Inconceivable!"

Try it. Same fan, same area of core, just thinner, lets say standard dual 1" tubes vs your triple 1" tubes. I you'll be surprised. Then you'll wonder "will it cool better even thinner", yes, yes it will. "up to what point?" you may ask. Well, we've done the work, we know. Look, they're wrong buddy, they really are.

Don't believe me, that's fine. I'm not sure if you have anything else "invested" into this, other than the purchase of your cooling system in post #1. If not, try it.

If there are other biases which are making you so determined on this course. Well... Good luck to you sir.
 
DeltaPAGJohn said:
"Inconceivable!"

Try it. Same fan, same area of core, just thinner, lets say standard dual 1" tubes vs your triple 1" tubes. I you'll be surprised. Then you'll wonder "will it cool better even thinner", yes, yes it will. "up to what point?" you may ask. Well, we've done the work, we know. Look, they're wrong buddy, they really are.

Don't believe me, that's fine. I'm not sure if you have anything else "invested" into this, other than the purchase of your cooling system in post #1. If not, try it.

If there are other biases which are making you so determined on this course. Well... Good luck to you sir.
Click to expand...

I think one thing that you may be missing with this audience is that our vehicles tend to have very limited real estate for cooling. So the challenge ends up being creating the most effective cooling system in the area available to us. In my buggy the absolute biggest rad I could fit is 16" tall x 26" wide and that is layed back at a 45 degree angle to fit under the hood.

Granted I'm only trying to cool 250hp but its not exactly idling along ever. Pushing 40+" tires at 30-40+ mph in the dirt is hard on a cooling system.
 
HYDRODYNAMIC said:
Sorry I didn't calculate your extra 4%
I see your pressure is even from hub to tip except for the red on the outer edges but how much static pressure can that blade pull?
Click to expand...
Depends at what RPM. The 18" I think most firmware we max it at 2,400rpm. At that rpm, the entire stall at a little over 2" H20. But you start getting significant stall near the hub north of 1" H20. At higher static pressure, the blade closer to the hub starts to stall. That can be offset by increasing RPMs. Similarly if a plane is pointing too up and not going fast enough it will stall and not increase altitude. To mitigate stall, increase speed.

We program our motors to run at optimal efficiency at around 0.5-0.6" this is where most heat exchangers are.

Once you debunk the "thick core is good" myth, you'll be in the same spot.
 
crazybluerider said:
I think one thing that you may be missing with this audience is that our vehicles tend to have very limited real estate for cooling. So the challenge ends up being creating the most effective cooling system in the area available to us. In my buggy the absolute biggest rad I could fit is 16" tall x 26" wide and that is layed back at a 45 degree angle to fit under the hood.

Granted I'm only trying to cool 250hp but its not exactly idling along ever. Pushing 40+" tires at 30-40+ mph in the dirt is hard on a cooling system.
Click to expand...
I understand that completely. Take the same electric fan, don't care whos, take a 4" (three 1.25 tubes) core radiator and a 2.2" (dual 1" tubes) core radiator same exact core surface area. The 2.2" core will cool better. Period.. . . .
 
I've been quietly following along quietly because I don't have the experience to have an opinion here so I'm just absorbing, but I appreciate the direction the conversation has taken.

DeltaPAGJohn said:
I understand that completely. Take the same electric fan, don't care whos, take a 4" (three 1.25 tubes) core radiator and a 2.2" (dual 1" tubes) core radiator same exact core surface area. The 2.2" core will cool better. Period.. . . .
Click to expand...

May I ask (from a completely uninformed point of view) which factor plays the most significant role in that statement - is it due to the increased resistance from the stack thickness, or is it due to the air becoming heat saturated to a point of steep diminishing returns in the first ~inch of core thickness?

I've definitely noticed the trend for modern OEMS to have pretty thin cores, I figured it was in part for its standalone efficiency but probably more due to keeping the combined stack thickness to a minimum on modern vehicles with big condensers and oil coolers in front of the rad, for the sake of the fans. But to hear that thin radiator cores would provide superior cooling even when space limited on core size is surprising.
 
DeltaPAGJohn said:
I understand that completely. Take the same electric fan, don't care whos, take a 4" (three 1.25 tubes) core radiator and a 2.2" (dual 1" tubes) core radiator same exact core surface area. The 2.2" core will cool better. Period.. . . .
Click to expand...
I just checked the specs and the rad I am running is 2.5" two core. I really don't have any complaints with my setup as it works fairly well now that I spent some time figuring out that most of the common aftermarket fans seem to cool poorly compared to OEM grade stuff. I went through three pairs of fans before landing on a set of factory Honda accord cooling fans with nice square metal shrouds that I could cut up and turn into a OEM looking dual fan setup that shrouded the entire core. The funny thing about this setup that may line up with you efficiency math is that these fans seem to draw less for the pair than most of the aftermarket ones were drawing each. I went from having 2 40 amp relay's, that I'd had to upgrade to because the first sets of fans were burning up 30 amp standard relays, to a single 30 amp for the Honda fans, following the factory stuff.

I'm just here for the learning and tech.
 
John ....

Elsewhere on the net, you state the construction differences between the SPAL & PAG units. Notably, the outer rotor vs inner rotor design. You even go so far as to say that one major disadvantage is that you can't waterproof the outer rotor style (which is what PAG uses). On your website, you're clearly (now) stating that the motor is waterproof. New design or something else going on?
 
AgitatedPancake said:
I've been quietly following along quietly because I don't have the experience to have an opinion here so I'm just absorbing, but I appreciate the direction the conversation has taken.



May I ask (from a completely uninformed point of view) which factor plays the most significant role in that statement - is it due to the increased resistance from the stack thickness, or is it due to the air becoming heat saturated to a point of steep diminishing returns in the first ~inch of core thickness?

I've definitely noticed the trend for modern OEMS to have pretty thin cores, I figured it was in part for its standalone efficiency but probably more due to keeping the combined stack thickness to a minimum on modern vehicles with big condensers and oil coolers in front of the rad, for the sake of the fans. But to hear that thin radiator cores would provide superior cooling even when space limited on core size is surprising.
Click to expand...
They are both important and one factor affects the other. The thicker core slows down the air due to resistance which mean less volume of air per minute (CFM). Less matter (air) to exchange heat to dissipate per unit of time. But also because air is slower, it reaches saturation sooner. its kind of a seesaw thing. When we design heat exchanger we try to hit the pinnacle point in our CAD/CFD modeling

yes, packaging for OEMs... anyone really, is definitely a challenge. I have clients with everything and the kitchen sink stacked infront of the radiator. yeah we have to design for that. or convince the client to get rid of it. Talking about stacks... BTW the same principle applies to those stupid 5" thick intercoolers. not sure, maybe.
 
WaterH said:
I have Four 12” Spal brush fans on my project truck. The specs from Spal are 1381 cfm with a 30 amp fuse. (I could not find a running amp claim) I personally measured 22 amps on one running. Your site says your 12” brushless fan pulls 2100 cfm at 14 amps. Can you break down where that efficiencies are coming from? Example 30% from brushes, 30% from smaller hub and 30% from better fan design.
Click to expand...

I would really like to hear where you think you efficiencies come from most.

DeltaPAGJohn said:
Once you debunk the "thick core is good" myth, you'll be in the same spot.
Click to expand...

I think your going to have trouble debunking this. If your saying the first core is doing more cooling than following cores, I agree. If you want to say the first core will do more cooling than multiple cores, I’m sorry I’ve seen that “myth” work several times. The only thing we changed was go to a thicker core.
 
Why are semi truck radiators really thick if thinner is better ?
 
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