Numerical Study on Heat Transfer Enhanced in a Microcombustor With Staggered Cylindrical Array for Micro-Thermophotovoltaic System

Abstract

In consideration of high heat transfer efficiency and stable combustion, a new type of microplanar combustor for micro-thermophotovoltaic (micro-TPV) system is proposed, in which the heat transfer is enhanced by staggered cylindrical array. The numerical study results indicate that the temperature of radiation wall of cylindrical-array combustor is higher and more uniform comparing with the conventional-channel combustor, the application of cylindrical-array make the effective radiation of the combustor increase 34.55% and reach to 35.98 W. Moreover, with inlet velocity increase from 4 m/s to 16 m/s, the cylindrical-array combustor shows the better stability of combustion, which the position of the flame moves 4.8 mm in the cylindrical-array combustor and 9.1 mm in the conventional-channel combustor. However, the 0.5–4.5 equivalence ratio range for stable combustion is slightly narrower than 0.4–6.0 in the conventional-channel combustor. To extend the equivalence ratio range, one row of cylindrical array was canceled, and the distribution length of cylindrical array was reduced to 10 mm, After this improvement, the equivalence ratio range is extended to 0.3–5.5, and the negative effect on the flame stability of the cylindrical array is basically eliminated.