Optimum convective heat transfer coefficient for diode-pumped laser slabs

It is important for laser designers to study the characteristics of heat tr ansfer from the laser crystal slab to the coolant in high-power DPSS laser operations. We have simulated and obtained the optimum heat transfer coeffi cient and coolant flow rate for our cavity design, in which the circulating coolant is maintained at a constant temperature. It has been determined th at the coolant temperature and the convective heat transfer coefficient (h) are important parameters in the thermal analysis. The coefficient h is aff ected by the coolant How rate, the physical properties of the laser slab an d the coolant and the pumping cavity geometry. Using analytical heat transf er equation, for cooling water temperature of 300 K, the optimum flow rate for our cavity geometry is found to be 390 cm(3)/s, corresponding to h = 5 W/cm(2) K. (C) 1999 Elsevier Science Ltd. All rights reserved.