Abstract:

A comprehensive basic analysis for various counter-rotating turbine is given with the blade element assumption. All possible typical schemes of counter-rotating turbine stage are enumerated. A typical three specification of each moving blade for blade element, such as impulse(I), reactive(R)and absolute axial intake, is suggested. Their performances of specific work, load distribution between counter-rotating shaft and efficiency are analysed for different shaft rotating speed ratios. It concluded that the load capacity per unit engine length of counter rotating turbine can be much higher than that of common tubine without efficiency penalty or ever with higher efficiency.

Key words: counter-rotating turbines, turbine analysis, basic stage