8 replies to this topic

[mariner]

Ina an interview with Racecar Engineering the head of Honda F1 design said that in 2022 they raised the operating temperature of the F1 engine so as to let Red Bull reduce the size of the radiators and associated ducting drag.

 

I can't see why running the engine hotter actually reduces heat output to the rads. as that is function of the thermal efficiency and the split of that into mechanical torque, exhaust  heat and coolant/oil heat. He didn't seem to imply running hotter increased thermal efficiency .

 

 

Is it simply that the hotter input temperature into each radiator gives increased heat dissipation in of itself?

[jcbc3]

Isn't it the other way round. Because lower/less cooling from smaller radiators, engine temperature automatically increase?

[Greg Locock]

A significant proportion of cooling is due to radiation and convection of the engine itself. This is roughly proportional to absolute temperature^4 (black body radiation)  and the temperature delta respectively. hence obviously a hot engine has more self cooling than a cold one.

[gruntguru]

Running the coolant at a higher temperature increases heat rejection from the radiators.

[DeKnyff]

If I remember well from my younger years, an internal combustion engine efficiency is related to the Carnot's cycle efficiency, which is 1-(T1/T2), T1 and T2 being the minimum and maximum temperatures of the cycle. T1 is the external air temperature, at least for atmospheric engines and is fixed at any given moment, therefore the only true variable is T2.

 

So, the higher T2, the higher the efficiency, which means more energy goes into pushing the pistons (engine power) and less energy is transformed into heat.

[Sterzo]

Is this perhaps a case of "how you tell it." Maybe he didn't mean they'd made any technical change at all, simply told Red Bull the engine could tolerate the higher temperature, which meant they could reduce the radiator size.

[Scotracer]

It's based on delta T. If your radiator can run hotter, it will reject more heat to the environment for a given cooling flow rate/temp.

[desmo]

What sort of coolant mixtures do F1 cars run? Is it stipulated (I assume so)?

[Oho]

water for safety reasons