The design of the spallation target system for accelerator driven systems requires a detailed understanding of the thermal-hydraulic issues involved as intense heat is deposited both in the window as well as in the target. Removal of heat from the window is a big thermal-hydraulic challenge. A lead-bismuth eutectic (LBE) experimental flow loop is currently being designed (1: 1 size of an actual target both in terms of geometry and flow rate) to study thermal-hydraulics of the target system. It is proposed to simulate the proton beam heating of the window with a plasma heat source. In this paper, flow simulation studies have been performed for different target geometries and flow configurations with different window materials, which are proposed for the above said experimental loop. Optimal values of window geometry and flow configurations including the thermal loads the window experiences have been arrived at along with the required parameters for the plasma torch. The plasma torch has been tested and found to be suitable for simulation of proton beam heating in LBE loop to be set up. (c) 2006 Published by Elsevier Ltd.