HEAT EXCHANGER component for Pneumatic systems?

Ideas
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1

Many small aircraft have their heating system working as follows:

  • A Ram air intake is routed through a heat exchanger sourcing heat from the engine
  • A simple manually-operated valve allows the heated air into the cabin

We do not have such component, the only thing we can do is route hot bleed air into the cabin.

I think this device will be quite simple. It only needs:

  • Input Line
  • Curve: Heat Added vs Source Var (SimVar / LocalVar)
    (can be as simple as a temperature delta, or proper thermodynamics)
  • Output Line
3

I agree with this. Through trial and error with the pneumatic system, I’ve discovered that trying to route hot bleed air into the cabin comes with it’s own issues in terms of cabin pressure, which makes it difficult to cool the cabin with a ram air intake bringing in cool air - the bleed air created a far higher cabin pressure than the ram air was able to overcome.

For reference, I was trying to simulate a small unpressurized cockpit where a relatively small amount of hot air is generated via the cabin’s proximity to a rather large engine immediately in front, and only a controllable cool air vent is provided to cool the cockpit.

I also discovered difficulties in getting the system to recognize when an interactive point is open, and thus normalizing the temp and pressure.

Having the ability to specify ram air as ‘heated by engine heat’ or ‘unheated, fresh air’ would allow for the cabin temp to be simulated while avoiding large differences in pressure.

4

Indeed simulating simpler aircraft requires thinking out of the box!
I used an outflow valve that I keep open. Bleed air is as low pressure as I can. A manual valve allows to tune its pressure.
In my real-world case, ram air is routed around the engine exhausts, and warmed up for the cabin. this competes with another ram intake leading straight into air vents in the panel.

This is quite a common approach to warm up unpressurized GA aircraft.

I also found out that you can leave the Circuit declaration our for a valve. It now works manually without dependency with electricals. Good for simulating air vents, manual controls, etc.

5

Thanks for the tip about an outflow valve; I hadn’t considered that. Might have to give it another go! That said, your original idea/suggestion is still a good one and would simplify the process a fair bit.