Heat transfer enhancement and pressure loss analysis of hydrogen-fueled microcombustor with slinky projection shape channel for micro-thermophotovoltaic system

Abstract

Micro thermophotovoltaic (MTPV) system, as a type of micro-combustion power system, possesses several advantages, including higher energy density, sustained and stable energy output, and significantly extended service life. The energy conversion performance of the MTPV system is known to be closely correlated with the thermal performance of the microcombustor. This study proposes a unique microcombustor for the MTPV system with a slinky projection form channel. The influence of the amplitude of the slinky projection, the slinky projection fins number, and the basic oscillating channel radius on the external wall temperature, temperature uniformity, and pressure loss are investigated by adopting the detailed hydrogen/air reaction mechanism with 3-D numerical models. The results show that the increase of the slinky projection amplitude and the slinky projection fins number can improve the external wall temperature. Compared to the traditional microcombustor, the average external wall temperatures of the microcombustor with a slinky projection amplitude of 0.4 mm are 31.6 K lower at an input velocity of 5 m/s. Additionally, when the input mixture velocity is 5 m/s, the average outer wall temperature improves by 29.4 K as the number of slinky projection fins grows from 10 to 42, and the pressure drop increases by 1.4 times. Furthermore, the basic oscillating channel radius is suggested to be 1.5 mm. In summary, this research provides a valuable method for enhancing the energy production of the MTPV system.