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.