Numerical investigation on a multi-channel micro combustor fueled with hydrogen for a micro-thermophotovoltaic system

Targeting at improving the energy output of the micro-thermophotovoltaic (MTPV) system, the heat transfer performance and energy output of the conventional micro combustor (CMC) and the multi-channel micro combustor (MCMC) with various channel shapes in the MTPV system are compared. The mean outer wall temperature of the MCMC with diamond channel is improved by 86.5 K than that of the CMC at the inlet hydrogen mass flow rate ((m)over dot(in,hydrogen)) of 1.64 x 10-6 kg/s. Furthermore, four arrangements of MCMC are compared in this work. The double-layer MCMC with layers counterflow exhibits the highest total energy conversion efficiency of 13.2% when the (m)over dot(in,hydrogen) is 8.10 x 10(-7) kg/s. The equivalence ratio (Phi) of premixed hydrogen/air plays a crucial role on the thermal performance of DMCMC-layer counter flow. The outer wall temperature and its uniformity becomes better as the equivalence ratio increases. The MPTV system with a DMCMC-layers counterflow can obtain an energy output of 19.3 W when the (m)over dot(in,hydrogen) is 1.64 x 10-6 kg/s and Phi is equal to 1. Namely, the multi-channel micro combustor has the potential to be a novel energy resource for the MTPV system. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study compared the heat transfer performance and energy output of different channel shapes MCMC and CMC in the MTPV system, finding that the MCMC with diamond channels had a higher outer wall temperature at a certain flow rate. Additionally, the double-layer MCMC with counterflow structure achieved the highest total energy conversion efficiency under specific conditions.