Research On Strength And Fatigue Life Of Combustion Chamber Of A Trubopropeller

This dissertation researches the strength and fatigue life of the combustion chamber of a trubopropeller. The applicability of the restriction-equations method in smooth structures,cylinder with fixture fringe and shell with fixture seat is validated by FEM analysis. The method of restriction-equations has good precision in plate, cylinder and with fixture fringe. The difference is a little bigger at the boundary, but it still less than 5%. The method can be used in engineering. In shell with fixture seat, the precision will be higher when the boundary is farther from the fixture seat. Stress analysis of the front combustor casing, the back casing and the flame tube on operation loads is made by ANSYS, the universal FEM software. The backside of underprop is dangerous area of the front combustor casing. The stress in the back casing is low. The dangerous area of flame tube is on the front edge of the swirler. The fatigue life prediction of the combustion chamber is obtained by nominal stress method. The fatigue life of the front combustor casing is 45709 cycles. The fatigue life of the flame tube is 9120 cycles. The back casing will not be cracked by reason of very low stress.