Heat exchanger element question

[AdrianC]

Hi, i do a motorsport where a normal cooling system for the engine cannot be used as it gets damage so we use solid water tanks along the bulkhead of the car, these arent the greatest as they tend to get hot as they're not really a cooling system at all. My idea would be to make a water tank, with a copper element inside which feeds the engine, and have cool water around it inside the tank to cool it down.

To ensure this works I'm guessing i need to know how long it would take to get for example 2litres of water inside the core around 98°c to heat up 20 litres of water around the outside of the core which should start around 20°c.

I know there are a lot of other factors involved, but keeping it simple, does anyone have a simple head conduction equation i could use?

Adrian

 

[Averagesupernova]

Not sure I understand what you are describing because it seems like what you propose is not really that much different than what you already have. Right now you have a tank that coolant is circulated through from the engine. Since it does not have enough surface area with air blowing over it everything tends to get too hot. So your proposal is to only circulate water through some copper line within the tank and use water/coolant surrounding it to cool what flows through the copper line. My question to you is (assuming I understand you correctly) why do you think this setup absorb heat longer than the way you are doing it now?

 

[AdrianC]

I assumed that because the hot water was contained within the copper coil, having cooler liquid around it, perhaps even icey cold, would cool it down? Or have i misunderstood and infact would the copper coil just heat up the tank of water?

Thanks for your reply

 

[Averagesupernova]

If the heat goes out of the coolant in the copper coil then it has to go somewhere and in your case it will go into the liquid in the tank surrounding the coil.

 

[AdrianC]

So would the tank with the coil in take longer to get hot than the standard tank? Also, how about putting a small amount of alcohol in with the petrol to reduce combustion temperature

 

[Averagesupernova]

Technically the tank with the coil in it would most likely take longer to heat up given that all other variables between the two situations are the same. But it also would take longer to heat up if it were not plumbed to the engine at all if you catch my drift. Designing the system so that the tank takes longer to heat up does not necessarily cool the engine better.

 

[philrainey]

maybe you want to fill the tank up with ice cubes before go time?

 

[philrainey]

I hope your tank has a pressure relief valve so if it gets too hot and boils it does not explode and kill you. And that the tanks are hydraulically tested to withstand a pressure above that of the pressure relief valve in accordance with the laws of where you are.