THERMAL STRESS AND HEAT TRANSFER ANALYSIS OF A THERMIONIC WASTE HEAT RECOVERY SYSTEM DESIGNED FOR A HYBRID ELECTRIC VEHICLE

This paper presents the simulation-based analysis and performance evaluation of a ThermionicEnergy Converter (TEC) system designed for automotive exhaust heat recovery. The proposedsystem, modeled using Multiphysics software, investigates the effects of various material propertiesand temperature gradients on thermal stress, thermal strain, and heat transfer efficiency. Highperformancematerials such as Tungsten and Molybdenum demonstrated superior thermionicconversion capabilities, achieving heat transfer rates of 1038.73 W and 985.43 W, respectively.Additionally, these materials exhibited low thermal stress and strain under operating conditions,validating their suitability for high-temperature TEC components. Coated Graphene showed thehighest heat flux (2107.09 W), indicating its potential for enhancing conversion efficiency, althoughpractical coating challenges remain. The simulation outcomes underscore the effectiveness ofnumerical modeling for material selection and design optimization in TEC systems. Future workinvolves experimental validation under dynamic thermal loads and further exploration of advancedcoating methodologies to improve TEC performance.