Recent content by ronb9956

I had not intended to start a discussion about tuned pipes. The question is: if we can add 6KW of heat energy to the total exhausted cooling air plus engine exhaust, is it possible to generate net thrust - or even just reduce the drag from the cooling air flow?

Restricting the exhaust flow may not be a problem. The tuned pipe needs back pressure to operate efficiently, the more the better up to the point where the engine runs too hot. A typical pipe has a cross section area of 100 sq mm at the engine end and 16 sq mm at the "stinger" (outlet) end.

I’m interested in your views on whether any significant thrust could be obtained using the cooling air and exhaust gases from a model aircraft engine. International class control line speed models (known as F2A) achieve speeds of around 300 km/hr using 2.5cc engines and tuned pipe exhausts that...