Combined coolant system idea
Combined coolant system idea
(OP)
I was thinking about all the things I need to keep cool on my engine.
1. Engine coolant
2. Transmission fluid
3. AC refrigerant (will be using AC to supercool liquid intercooler fluid)
4. Engine oil
5. Power steering fluid
So many things to mount up front and try and keep cool. Then I figured, maybe there is a way to combine them.
Here's what I came up with.
ONE air/water heat exchanger for everything. A real thick radiator perhaps, but better IMO to build a shroud to match the opening at the front of the car, and get a intercooler core that's 3-4.5" thick to fit in it, and run the fluid through the ends that would have been for charge air.
The water circulated through the intercooler/radiator will lead to a big heat exchanger. The exchanger will be a piece of 5-6" aluminum tubing, with several smaller tubes running through it end to end, one for each of 1-5 listed above. The water coming from the intercooler/radiator won't have it's own tube, rather it's flow will go through the main 5-6" tubing, around the smaller tubes, exiting offset at the other end of the cylinder.
Now the tricky part is the sizing of the individual tubes for 1-5. A larger diameter gives slower flow through speed, and more surface area, acting to increase the heat exchange rate for that particular fluid. I'll crunch more on this later.
So, seem like a neat idea? I like it much better than 5 individual coolers sandwhiched in odd ways, and a lot of airflow going past or around them as a result.
1. Engine coolant
2. Transmission fluid
3. AC refrigerant (will be using AC to supercool liquid intercooler fluid)
4. Engine oil
5. Power steering fluid
So many things to mount up front and try and keep cool. Then I figured, maybe there is a way to combine them.
Here's what I came up with.
ONE air/water heat exchanger for everything. A real thick radiator perhaps, but better IMO to build a shroud to match the opening at the front of the car, and get a intercooler core that's 3-4.5" thick to fit in it, and run the fluid through the ends that would have been for charge air.
The water circulated through the intercooler/radiator will lead to a big heat exchanger. The exchanger will be a piece of 5-6" aluminum tubing, with several smaller tubes running through it end to end, one for each of 1-5 listed above. The water coming from the intercooler/radiator won't have it's own tube, rather it's flow will go through the main 5-6" tubing, around the smaller tubes, exiting offset at the other end of the cylinder.
Now the tricky part is the sizing of the individual tubes for 1-5. A larger diameter gives slower flow through speed, and more surface area, acting to increase the heat exchange rate for that particular fluid. I'll crunch more on this later.
So, seem like a neat idea? I like it much better than 5 individual coolers sandwhiched in odd ways, and a lot of airflow going past or around them as a result.





RE: Combined coolant system idea
RE: Combined coolant system idea
RE: Combined coolant system idea
RE: Combined coolant system idea
Let's assume that you have your all-in-one heat exchanger. What temperature are you going to run it at?
1) If it's too low your engine will run at too low a temperature and lose efficiency. If it's high enough to keep the engine happy, it will be way too high for what your air conditioning condenser would like.
2) Consider coolant from the engine that exits the engine taking a certain amount of heat. For argument sake, let's say that the temperature coming out of the engine is 200 deg F, and it is cooled to 180 deg F in the radiator when it is routed back to the engine. If the ambient temperature is 100 deg F, the radiator will see a temperature gradient of about 90 deg F (not exactly, but close enough for argument purposes).
Now consider your new system. What did you say the temperature of the heat exchanger circuit going to be? If it's 100 deg F, then you will need a coolant system heat exchanger about one-half the size of your present radiator (not exactly, but work with me here). But, there's a slight problem. . . . .If your heat exchanger circuit is working at 100 deg F, and the ambient temperature is 100 deg F, then your new radiator/intercooler will have to have infinite heat conductance -- and that's not going to happen.
How about if you split the difference of your heat exchanger fluid temperature, and operate it at 140 deg F. With the lower temperature gradient (190-140) your engine coolant/new cooling system heat exchanger will be about the size of your present radiator. But your new radiator will have to be about twice the size of your old one. So now you have to have three times as much heat exchanger surface as you did when you just used a simple coolant system radiator.
Now since we haven't discussed the oil and transmission coolers, I've underestimated the amount of cooling surface you will need for your new intercooler/radiator system.
I hope I've been clear in what the problems are. Since you are now transferring the heat through two heat exchangers, you will need at least twice the cooling capacity that you have now -- first for the engine coolant/new coolant system heat exchanger, and the second for the new intercooler/radiator device that you have.
RE: Combined coolant system idea
Also, you made these claims of heat exchanger surface area but missed the fact that a normal radiator is a air/liquid heat exchanger, but the engine coolant and main coolant will be a direct water/water contact. I don't need a massive amount of surface area. Water has about 25x the thermal transfer rate as water.
RE: Combined coolant system idea
1. AC refrigerant can't be overcooled. The colder it is before going to the evaporator, the better.
2. The oil, if cooled through the main exchanger (may not need to), will have a thermostat for that too.
RE: Combined coolant system idea
Regards,
MB
RE: Combined coolant system idea
power steering coolers generally are just steel power steering lines zigzagged back and forth a few times..... as simple as it gets
oil and tranny coolers are generally in the radiator and although they dont cool down below the coolant temp, they cool as well as you want them to in most cases, if not, its very simple to throw an external tranny/oil cooler in front of everything. This setup is also very simple, and if the coils in your rad go bad, just buy one of these seperate coolers and your good to go..... 50 bucks later
most newer cars/trucks are very good at directing air flow through the heat exchangers with shrouds and fans, having them seperated, in my opinion, helps them dissipate heat better and prevents one system from overheating the other as much.
If the condensor goes bad all i need to do is replace just it, or if my radiator clogs, all i need todo is replace it.... not the whole system.
Maybe im just not visualizing your idea that well, I just dont see the benefits other than how it might cool alittle better.
RE: Combined coolant system idea