Firstly by
rotary I mean the Wankel as opposed to the static crankshaft with rotating cylinders (eg: Gnome).
I've been reading a bit about ways of powering the GA fleet other than the traditional big displacement piston engines and especially like the diesel and rotary engines.
Good points for the diesel:
- the fuel (availibility, calorific value and volatility compared to avgas/mogas)
- efficiency
- lack of ignition system (interference, complexity)
- no carby (icing)
Good points for the rotary:
- few moving parts (simple)
- in theory (is it just
in theory?) it looks very reliable (straight shaft, solid construction because it can be)
- love the continuous rather than reciprocating motion - seems much less stressful
- low vibration
- low weight-to-power
So, combining the two, how about a compression-ignition rotary engine? Use the rotor, housing and eccentric shaft setup, replace the spark plugs with high-pressure injectors and increase the compression ratio somehow. Could it be done?
Potential problems:
- Would have to master the apex/face sealing problems in the rotary for the high levels of compression
- To achieve the high CRs may require a very accurate manufacturing process for the rotor and housing (?)
- Would the surface-to-volume ratio of the combustion chamber pose any problems for AVTUR / diesel?
- Must be others...
Is this a bit far-fetched
- any thoughts?