NUMERICAL SIMULATION OF THERMOMECHANICAL BEHAVIOR OF EVAPORATORS FAN IN A NEGATIVE COLD ROOM

This work is a contribution to the study of the influence of the operating cycle of a negative cold room on the thermomechanical behavior of evaporators fan blades. The objective was to demonstrate the effect of cyclic and continuous variation of the operating temperature of 20°C to -20°C on the appearance of cracks on the fan blades. Throughout this study, the effects of mechanical vibration have been neglected. The temperature gradient and the stress field in the material was estimated using Hoai model. Bueckner and Paris model was used to evaluate the stress intensity factor in order to determine the lifespan of the fan blades on the evaporator of the freezer rooms. The equation system chosen was solved by the application of the method of separated variables and dichotomy. The results show that the temperature field generated by either a short or long operating cycle does not have a considerable effect on the thermomechanical behavior of the fans. The breakage of the fans may occur after minutes and minutes respectively during operation of the freezer room’s short cycle and long cycle.