FADHIL, B. M.: Effect of pressure angle associated with rim thickness on gear tooth crack initiation and crack propagation path - numerical study 61 MADARÁS, J., FERENCEY, V., BUGÁR, M., GOGA, V.: The simulation of starting torque impact of an electric motor for the dynamic behaviour of the electric vehicle transmission mechanism 83 WANG, C., CUI, H. Y., WANG, R. X.: Loaded tooth contact analysis of modified double helical gears 95 BARTA, D., REPKA, J., TUČNÍK, P., SANIGA, J., MRUZEK, M., KUKUČA, P.: A non-conventional Stirling engine with FIK mechanism 109
B. M. FADHIL
A numerical model study was performed to investigate the influence of the gear pressure angle associated with rim thickness on gear tooth crack initiation and propagation besides the fatigue life. Three values of pressure angles (15°, 20°, and 22°) were taken into account associated with three values of rim thickness. Finite element programs FRANC2D and ABAQUS were used to simulate gear tooth initiation and propagation. The analysis used principles of linear elastic mechanics. FRANC program had a unique feature to automated crack propagation using automated re-meshing scheme. The computed stress intensity factors were used to determine the crack propagation direction. With the simple Paris equation, the fatigue life has been calculated. The results show that the gear pressure angle associated with rim thickness has a significant effect on the crack initiation position and crack propagation path in addition to the fatigue life.
J. MADARÁS, V. FERENCEY, M. BUGÁR, V. GOGA
C. WANG, H. Y. CUI, R. X. WANG
This paper performs loaded tooth contact analysis of modified double helical gears by proposing a method that combines the mathematical programming method with finite element method. Firstly, based on reducing vibration and noise and raising working efficiency, the method of three segment modifications for pinion profile is presented. Cutter surface equation is deduced by changing the shape of cutter-edge, substituting three segment parabolas for the line. Secondly, according to the condition of compatibility of deformation, force equilibrium and the non-embedment, the model of loaded tooth contact of double helical gears is obtained. LTCA program is developed successfully in a personal computer. By using this program, tooth load distributions and loaded transmission error are obtained in a meshing period. Finally, the comparison experiment of loaded transmission error both before modification and after modification is carried out. The results indicate that the LTCA method of modified double helical gears is reliable.
D. BARTA, J. REPKA, P. TUČNÍK, J. SANIGA, M. MRUZEK, P. KUKUČA
The paper deals with a design implementation of Stirling engine with a non-conventional FIK mechanism, contains a description of its operation and discusses the possibilities of compression ratio changes. It presents the results of research focused on individual parts of the engine, including the regenerator, heat transfer and FIK mechanism. These results have been obtained by calculation, simulation and experiments performed directly in selected engine parts. The software FLUENT was used for the simulation.