Constructal heat release of radial permanent magnet generator

Constructal theorem indicates a pattern of optimum efficient flow in a form geometrical design. A permanent magnet generator should keep its permanent magnet temperature below its critical. The constructal pattern in the form of rotor and stator radii ratio was studied for optimum heat flow generated from losses. A theoretical approach was applied to a 2D model of radial permanent magnet generator assumed to have specific thickness of the laminated core for its stator. The heat was released to the frame in order keeping temperature of the magnet below its critical temperature as the main requirement for performance. Geometric parameters showing thickness and width of the stator were found as the constructal pattern that meet the targeted output. Ratio of the stator and rotor radii proportional to magnetic field strength, square of convective coefficient, and inverse of conductive coefficient are shown as the solution of minimizing the rotor temperature.