Looking for someone that wishes to get into a discussion about thermodynamics as applied to our beloved intercoolers. Please look at the water circuit in the photo below for reference to see that the factory intended the water take three circuits within the I/C. It is a counter flow design and is intended to extract the heat from the air in a series fashion.

Premise: Would you gain cooling ( now that we have super coolers and bigger pumps 0) with a single pass of cool water from right to left, rather than three smaller passes???

I am believing that the greater flow of water ( and greatly lower restriction - three parallel circuits as compared to three series circuits - a 9 to 1 lower friction path) would insure a greater delta T from the water to the air circuit.

Currently the cold water goes across the outlet of the I/C; then warmer it goes across the middle of the I/C; and then ,,,,and then it is hotter going across the inlet to the I/C where the air is also the hottest.

Iam wagering that the cold flow of water across the three circuits in PARALLEL would achieve greater heat rejection.

Please remember that the original factory H/E was terribly small, out of the fans air stream and restrictive.

WHAT SAY YOU< Over. Woody





https://www.crossfireforum.org/forum...rochargedc.jpg

https://www.crossfireforum.org/forum...er-xxx-img.jpg

 

I completly disagree with you!

 

No you don't.

 

The trouble with parallel circuits is that the water will always pass through the closest to the exit circuit or the easiest circuit to traverse. This can lead to blockages in some areas as small particles can start large blockages which only get bigger. That would only be a problem with coolant with particles suspended in it.

The speed at which the water travels will be on average 1/3 of the velocity of this series circuit when ignoring frictional and pressure drops. Hence the volume will need to be increased,but not by a factor of three maybe two would be sufficient. The speed has to be kept up to reduce or eliminate lamina flow, that is awkward in this case as there seems to be rectangular passages and the corners are a problem.

Turbulent flow is a must or the sluggish lamina flow layer will act as an insulator.

 

I completly disagree with both of you now.

 

180, note the inlet and outlet are are at opposite diagonal corners. I have a solution to the flow rates balance issue.

The 1/9th restriction would promote more flow and 2: 1 is a good estimate, I concur with you on that one.

With Twice the flow and greater temperature differentials, it feels like this could be better than factory cooling, I.E. lower IATs. [ given the massive increase in pump and h/e sizes].

The path restriction-friction would be 1/9 the stock restriction and about 3 times the cross section and maybe twice the flow, should be non turbulent due to the lower rate of flow per channel. BAD MATH WARNING; 2x flow, divided among 3x tubes =about 2/3 rate of flow or 3/2 as much latency time = = better heat up take.

I really dont want laminar flow, need to scrub off the boundry layer / film layer. Rather be in the goldie locks region somewhere in the middle.

OVER.

 

I don't think you paid for this argument, so I am not going to argue with you anymore. If you want a freebie you must be one of the 47%.

 

I completely disagree 110% with all of the posters above.. and all of the posters below

 

Similar to Dave's concerns, my fear would be that the fins furthest from the inlet/outlet would be "out of the loop" no pun intended.

Also, my other concern is the pressure in general. While the Johnson pump flows more, I'm not entirely sure there's enough muscle to push the entire collective volume of water through the fins at once. Also, the "returns" on each side allow the resistance to balance out, whereas if all vanes were used at once, the resistance acting upon the water would be much greater than it would be on any single "pass" in the three stage system. Think 100' hose versus a 10' hose... the water has to be pushed much harder to flow through 100' of pipe at the same CFM as a 10' pipe. Hopefully that visual makes sense.

Finally, the coldest water being furthest away from the intercooler inlet (factory setup) makes total sense. Assuming a given temperature on the inlet side, the channels furthest away from the inlet (near the Y-pipe) would not have nearly the cooling effect... the cooling curve would be much more gradual. In the factory setup, the air is cooled as it passes each bank, passing by the coolest row of fins on its way out. Put another way, ice cubes are much more efficient at cooling soda than cooling coffee. If all fins were equally warm, the cooling curve would be much flatter.

There's no question the intercooler core's integrity leaves a lot to be desired. One would think such a failure rate during assembly would result in a scrapping of the unit. But, that's Mexico-based Garrett for ya.

Too bad we can't ask BEGi for WTA cores

 

Once this suckers welded up who knows what ills hide inside and how many do you test destructively to find out the problems that are hidden.

 

Instead of pushing water thru circuit#1 and then #2 and then #3 is three times the restriction of one circuit path; agree??

Going thru three paths in parallel is the electric equivalent of three parallel circuits or 1/3 the resistance of a single path.

The overall restriction was 1+1+1=3

The parallel circuit would 1x1x1/1+1+1 or 1/3 thus 1/9 the restriction.

Iam getting ready to tear off my IC to cut into it and do this to prove it, gotta medicate myself.... Remember the flow rate with my super cooler was above 3 gallons per minute with the entire IC circuit in place. !!

Woody

My goal is to scrub more heat from the IC. Colder water in all three sections at the same time, sure has me convinced so far.

I have begun to consider the opportunity to possibly fix these leaky *******. Seems do able. WW

 

You're wrong, Romnie's going to win!

 

WTF ? where did that come from?

 

Ill start off by stating that im no engineer, not by any means. I am however a very mechanically inclined technician that works on a lot of mobile equipment that often deals with hydraulic systems retaining excessive heat.
From my experience with a typical fluid to air heat exchanger, a parallel flow of fluid through the exchanger is the most common method employed. I personally believe this has more to do with cost effectiveness, vs heat shedding potential.
I like John's analogy of pushing water through a hose. While a longer hose may provide more resistance to the flow of the water, the longer continuous length will provide better overall cooling efficiency. I think the increased resistance to flow might not be a bad thing either. It takes time for fluid to transfer heat to any material. Slowing fluid flow down is an old hot rodder trick to keep flathead Fords from overheating. You can move fluid too fast to effectively cool your system down, simply by not allowing time for heat transfer.
Case and point, my hot tub. Same heater, the tub will heat up faster on low pump setting than high because the fluid moving past it is absorbing more of the energy put out by the heater.
Heating and cooling go hand in hand. If you can transfer the heat to the fluid effectively, you can more effectively transfer the heat back out on the other side.

 

I win! Everything you wanted to know and more..

Comparison of Heat Exchanger Types - Engineers Edge

 

There are three things that need to be taken into consideration when designing a cooling circuit and Woody, you should know this like I know this car...

1) You need to have the ability to evacuate the incoming medium (coolant or water) at a rate of 1+:1. This is why you have small registers and large returns. You have a pump (fan) that pushes air through your home but said fan also has to push said air back to the exchanger or distributor.

2) You need to have adequate flow. It doesn't matter how cold you get the medium you're using to remove the heat if you don't move it through the circuit as quickly as you can. With these cars, there is no limit to the amount you can move through without reaching saturation unless it's 100+ gal/min, it's saturated before it gets to the outlet. More powerful pump, move more fluid, remove more heat.

3) You need a way to remove the heat from the saturated medium. Like an air conditioner, unless you can get the medium cool again, the next time it passe through the cooling circuit, it will become saturated sooner. Increase the size of the heat exchanger, you add more surface area for the cooler air to cool the heat saturated medium. If you add a reservoir to the circuit, you can most times completely mitigate this due to the increase in volume and the ability to increase the cooling capacity of the circuit by changing out the water or by the addition of ice.

That being said, a single-pass or triple-pass intercooler will only work as well as the rest of the cooling system it's part of. If your only upgrade is a heat exchanger, you should stay with the triple-pass IC because you aren't moving enough volume. If you have a high-flow pump and a larger heat exchanger, a single-pass IC will only show slight gains but shouldn't be overlooked due to the fact any gain in cooling and resultant lower intake air-charge temp translates into more power. This is one of those bang-for-buck decisions. If you have a large heat exchanger, a high-flow pump and a 3-4 gallon reservoir, a single-pass intercooler will really impress and with the addition of ice, can actually yield charge-air temps lower than ambient!

Take care

 

"NASTY, this is in our cars, but I have a plan and will test a fix." Woody

Looking forward to your plan professor!

 

I have some experience with the cooling of plastic injection molds and the faster you put the water through the mold the colder it gets. If the mold gets too cold the plastic will set up before the mold is completely full. Slowing the coolant down enables you to get the correct balance between the properly warm mold and the plastic part setting up in a reasonable time. Slowing the coolant down too much and the part will take too long to set up. So we can conclude that the flow rate of the coolant has a direct effect on the temperature of the mass it runs through.

Once turbulent flow is achieved there are diminishing gains to be had from increasing the flow rate. Using antifreeze diminishes the effectiveness of the coolant and makes it harder to achieve a turbulent flow due to its viscosity. It is easier to get turbulent flow in water than treacle.

The closer the air and coolant are to one another the slower the heat transfer. Just take an ice cold shower to prove this in reverse, you will agree well before hypothermia sets in.

 

a few points to consider if you will

generally speaking the faster the flow rate the better the ΔT's. the medium's total residency time in either the I/C or H/E remains the same over long periods of time, just in shorter periods.

assuming proper flow rate and H/E, a single pass I/C will most assuredly perform better. the best heat absorption occurs with the highest ΔT's and a triple pass can actually degrade the performance. how much better a single pass performs is a vaild question, but it will be better.

another factor in heat absorption of the medium are any additives beyond normal distilled water. Anti-freeze has a poor heat coefficient roughly 1/3 of water i believe. the higher the heat coefficient the higher the heat absorption it can achieve.

laminar flow is a bane to heat absorption. optimum heat transfer is achieved with water impingement on the target areas. question is how to achieve this in a unit like an I/C. i have no answer for that one.

anyways, my thoughts.

 

sound like a lot of hot air.....or water in this case.... I think I will just wedge a few runs of pipe under the S/C and pour in a little liquid nitrogen before each race....to supplement the inner cooler....