Influence of the crack propagation velocity on heat release in compressor blades during fatigue tests

In this work, the influence of the crack propagation velocity on heat release in blade was shown. Research was be performed during fatigue test of the compressor blade. In the investigations, the blade with the V-notch was examined. The blades during experiment were entered into transverse vibration by a vibration system Unholtz-Dickie UDCO-TA-250. The crack propagation process was conducted in resonance condition. The blades were periodically bended what simulates geometry changes during operation of the engine. The main part of the work is based on research of fatigue. During investigations both the amplitude of the crack length and also the blade tip displacement were controlled. Additional velocity of crack propagation was measured by change of a crack length in time. In the same time temperature, distribution pictures were observed. The taken picture was used to exhibit the phenomenon and shown the heat propagation direction. The main results of presented investigation are both the parameters of a crack and the crack growth dynamics in the compressor blade subjected to vibrations. An additional original result of the work is connection between velocity of crack propagation and temperature distribution taken from picture. The result of above analysis can be used in determining the amount of energy released during the cracking process and evaluate the amount of energy required for the growth of a gap. In this work, the capabilities of the proposed method and the problems associated with it were defined. The results presented in this paper have theoretical and practical value.