25121

محاسبه عددي و المان محدود خستگي اتفاقي بوژي H در حوزه ي زمان و بهسازي آن براي افزايش عمر با در نظر گرفتن ويژگيهاي مسير

كارشناسي ارشد

مهندسي راه آهن گرايش ماشينهاي ريلي

1397

تير 1400

دكتر داوود يونسيان

مهندسي راه اهن

1400/06/03

Numerical calculation and finite element of random fatigue bogie H in the time domain and its improvement to increase life by considering the characteristics of the path

1/1/1900 12:00:00 AM

In case of accidental fatigue of railway lines, which is the result of unpredictable and accidental forces due to roughness and rail connections, conventional theories and methods cannot be used to calculate the life of fatigue, so these methods will not work. In this dissertation, with the help of numerical solution, the life of the frame of high-speed passenger buses KTX-I and Manchester train is predicted. In the first stage, by dynamic simulation with real input from the rail line with the help of UM software, a complete dynamic solution is performed and the forces acting on the bourgeois frame are calculated. In the next step, the bogie frame is elemented by finite element methods and with the help of Abacus software, and by the single force method, the stress conversion matrices required for the numerical solution of the life prediction are extracted. Then, using various disproportionate methods, Abacus output matrices, UM output forces and material definition, the life and location of cracks are predicted using Fe-Safe software. Finally, by comparing the three different modes of the line class, the weight of the wagon and its speed, the bogie frame has been improved. The results show that by changing the line class from 4 to 5, the life of the boogie is increased 2.5 to 3 times, while its life in line 6 is about 250 to 300 times that of line 4 and 5. Also, in relation to the effect of weight and speed, it was found that with increasing each life, it decreases, which is completely linear up to a certain speed and weight, and then, compared to each line class, the life of the bogie decreases exponentially. In the discussion of improvement, there is a 30 to 40 percent increase in life in line 4 class, if the maximum increase in life in line 6 class is 15 percent.

Rail irregularity, Actual loading, random fatigue & Random forces