/diy/ - Do It Yourself

>>1003086
>Good luck casting superalloy.
Watch the video: [>>1002213]
>it needs to be singlecrystalline.
>>1003107
>Airplane-style jet engines are dynamic-thrust engines, most of their energy output is in direct intake-exhaust thrust.
There are several turboshaft engines that are based on jet engines which simply have the nozzle (and afterburner, if applicable) removed and a separate power-recovery turbine attached instead.
https://en.wikipedia.org/wiki/General_Electric_LM1500
https://en.wikipedia.org/wiki/General_Electric_LM2500
https://en.wikipedia.org/wiki/General_Electric_LM6000
Several turbine RC helicopter engines work the same way, starting with a model turbojet and attaching a power recovery turbine with output shaft to the exhaust.
>So if you want it to be very efficient at all, it has to be engineered (the mechanical properties AND the internal flow design) to operate normally at 90-95% of its maximum RPMs.
Temperature is the more pressing limitation for efficiency. It's possible to overengineer the turbomachinery to withstand even higher RPMs, but generally engine designers don't make the RPM limit any higher than it has to be in order to reach operating pressure ratio and temps. Doing so allows them to design the engine with less material, reducing both weight and cost.
>where the gas goes in the GSM pressure has to be higher than the air compressor section.
No, it doesn't. In fact, achieving that condition is impossible. Pressure at the turbine inlet can only be less than or equal to pressure at the compressor exit.
>Also the amount of nozzles on the compressor section have to be thought of for even heating of the combustion blades
I don't even... what?