The Turbine Rotor Analysis Of The Contact Stress And Stress Intensity Factor

Using the finite element software ANSYS, this paper computed the contact stress, structure optimal, stress intensity factor(SIF) of crack and its remain life in aero-engine turbine disc , the specific details are as follows:1. Building the finite element modal of turbine rotor and turbine disc, analyzing the contact stress of turbine disc and turbine blade, discovering: contact stress increase with the position of flank, the maximum stress appears at the last of flank.2. This paper carried on the structure optimal, discovering: i)The contact stress in the flank increase slowly with the increase of flank angle. ii)With the friction coefficient increasing, the contact stress in flank decrease, iii) the contact stress won't change at the back of 0.25.3. The theory of calculating SIF of composite mode crack was set up, the results show that: i)the result of ANSYS is almost equal to analytical result, which prove that the method is feasible. When the crack is very big or very small, the result of ANSYS'error is comparatively obvious , that is due to the problem of the precision of gridding.4. The finite element software ANSYS was expanded to compute SIF, computing the SIF of unilateral oblique crack, central crack, central oblique crack, cracks at hole. The results were acquired as follows:Unilateral oblique crack: i) with the angle increasing, the SIF of mode I increase all along, but the SIF of mode II in unilateral oblique crack increase first, decrease then; ii)with crack length increasing ,the SIF of mode I and mode II increase; iii)the effect of pate length is obvious at small plate, when the plate length reach a certain value ,the effect can ignore entirety. Those results are useful to study crack for the future.Central crack: i)With the length-width ratio increasing, the SIF decrease, and this change can be neglected at the back of 1.5.Central oblique crack: i) with the angle increasing, the SIF of mode I increase all along, but the SIF of mode II increase first, decrease then; ii)with crack length increasing ,the SIF of mode I and mode II increase. Cracks at hole: i)With the hole increasing, the SIF increase obviously. ii)When there isn't no hole, the crack become central crack, whose SIF is most smallest. iii)When the hole is small, the value of SIF is almost equal to the SIF of radius add to crack length.