Oil temperature after shutdown

[sobek]

Here's one for the RL helo-mechanics,

 

namely, why do the oil temperature gauges for the engines keep rising after engine shutdown?

 

cheers

[mvsgas]

I am not sure about helicopters or the KA-50, but in other jet aircraft, the oil warms up after shut down of the engine because it is not longer being circulated through a cooler (being a fuel oil cooler or a heat exchanger, or a oil air cooler)

[JDski]

Yea this is pretty much the case with all engines. I believe there is a cool down period that you should leave the engines running at idle before you shut them down. They will still probably get warmer after shutdown, but not as much as if you shut them down right after landing.

[AlphaOneSix]

the oil warms up after shut down of the engine because it is not longer being circulated through a cooler

 

Bingo. In the case of the Ka-50, oil from the engines and main gearbox gets routed through a set of radiators and is cooled using air. When you shut down, air is no longer being forced through the coolers, so the oil will warm of briefly before cooling down.

[AlphaInfinity]

Bingo. In the case of the Ka-50, oil from the engines and main gearbox gets routed through a set of radiators and is cooled using air. When you shut down, air is no longer being forced through the coolers, so the oil will warm of briefly before cooling down.

 

Like my daddy always said..."If you overheat your engine, pull over don't shut the engine off!".

[AlphaOneSix]

The reason for idling the engines for two minutes before shutting down has nothing to do with the oil temps, though. It's to allow your turbine disks to cool down a little. If you shut down your engines immediately from full throttle (AUTO), you run the risk of the engine casing cooling faster than your turbine disks, raising the possibility that your turbine disks might rub against the inside of the engine casing. As you can guess, that would be bad. Don't think that's modeled in this game, though.

[Focha]

Also and to complement others knowledge, as you probably know cooling or heating a material too fast will fatigue much more the materials and that is something you don't want at least if you are not the richest person in the world.

[Yo-Yo]

Here's one for the RL helo-mechanics,

 

namely, why do the oil temperature gauges for the engines keep rising after engine shutdown?

 

cheers

 

 

The heat circulation model in DCS is based on heat transfer equations and the effect is due to the heat transfer from the hot engine body to the oil.

As the fan stops after shutdown the radiators do not dump heat to the air.

By the way try to take a look at the temperature gauges during the hovering, the flight, at different OATs.

[JG-1_Vogel]

Wow... you don't really think about these little things. To see that something so small like that is modeled it really makes me amazed at the depth of this system in terms of system modeling... its mad!