Effect of liquid saturated porous medium on heat transfer from thermoelectric generator

Abstract

Low-temperature heat sources are widely available in nature, they are considered to be unusable, even though the conversion of such low-grade energy into electricity (high-grade energy) is highly desirable. Thermoelectric generators (TEGs) are achieving increasing interest in converting low temperature heat into electricity. TEG suffers from low performance, improving the performance of TEG will allow there use in huge engineering applications. In this paper the effect of heat transfer rate on the performance of TEGs will be analysed under both steady and transient conditions. Enhancing heat transfer from the TEG surface will be studied using a liquid saturated porous medium. Aluminium and copper particles are used and their influences are compared to forced convection heat transfer from TEG surfaces with and without liquids. The experimental results showed that power generated with Cu particles exceeds that of Al particles with 14%. The free to forced convection power generation ratio was 26.5% for Al,36% for Cu and the enhancement of TEG performance reached 149% for liquid saturated Cu particles.

Keywords

• Thermoelectric generator
• Liquid evaporation
• TEG performance
• Porous medium
• Enhancing power generation
• Low energy harvesting