Mass transport, corrosion, plugging, and their reduction in solar dish/Stirling heat pipe receivers

Solar dish/Stirling systems using sodium heat pipe receivers are being developed by industry and government laboratories in the US and abroad. The unique demands of this application lead to heat pipe wicks with very large surface areas and complex three-dimensional flow patterns. These characteristics can enhance the mass transport and concentration of constituents of the wick material, resulting in wick corrosion and plugging. As the test times for heat pipe receivers lengthen, we are beginning to see these effects both indirectly, as they affect performance, and directly, in post-test examinations. We are also beginning to develop corrective measures. In this paper, we report on our test experiences, our post-test examinations, and on our initial effort to ameliorate various problems.