This paper presents a way to design a finite-element computer model of cooling system with a complicated geometry. The computer model is developed on the basis of a commercial software package ABAQUS. The steady state forced-convective fluid cooling of a pin-fin heat converter for power (similar to1 kW heat power) semiconductor module has been investigated on the basis Of computer simulation. A phenomenological equation has been used for calculation of the local Value of the heat transfer coefficient for the liquid-solid interface. The impacts of the thermal conductivity of the pin-fin sink material, volume flow rate of the cooling liquid and geometrical design of the pin-fin sink on the thermal resistance of the converter are shown. Copyright (C) 2003 John Wiley Sons, Ltd.