Flow Analysis Inside the Blade of Tip-Jet Cold Cycle Helicopter

This paper is focused on the flow inside the blades of cold type tip-jet helicopters. The phenomena of additional compression of the air through the blades due to the existence of the centrifugal effect shows that there is more potential in such types of tip-jet helicopters compared to hot cycle ones. CFD 3D analysis is used to simulate the flow and results are compared to values obtained by 1D hand calculation with differential equations. Results clearly indicate that not only all pressure losses, i.e. pressure drop, inside the blades are compensated by effect of centrifugal force there is a significant increase of pressure at the blade tip.