Using Finite Difference to Determine the Temperature Field in Alternators 860586
Analytical and experimental studies were conducted to determine means to decrease the temperature rise in the rectifier and rear housing of a small-frame alternator. An interactive computer program based on finite difference, ITAS (Interactive Thermal Analysis Systems), was used to analytically determine the temperature field of the alternator. The analytical results (including steady-state energy balance) were then used to guide the experimental effort, Best performance was achieved with a modified system design which included changes in the air flow path, finning the rectifier directly, and using an improved fan. This resulted in a temperature drop of 30 deg F over the entire operating range for the 40-amp modified alternator compared to the original design.