Heat and mass transfer mechanism of micro-combustion system with dual-fuel at high environmental load

Heat release and mass transfer characteristics in micro power unit with dual-fuel at high environmental load are mainly investigated in this paper. Energy conversion equations are solved in both phases separated by a regressing gas-solid interface. The igniter jet is assumed as a cross flow and then added to the gas governing equations in the form of source terms. Analyses have focused on variations in temperature, heat release rate per volume and species concentration. Results show that the forced-convection heat transfer in the gas flame zone is performed under the effect of the cross flow. Meanwhile, the rapid depressurization process of the micro system results in an adiabatic expansion phenomenon of the combustion-gas near the solid surface. However, the sandwich propellant can always keep burning due to the continuous addition of energy source from the igniter combustion-gas of high temperature. The out-of-phase blowout effect, that is, the gas zones with strong heat release always keep away from the solid surface, also appears in the whole process. Significantly, when the initial pressure or the average flow velocity of igniter jet is lower than 20 MPa or 40 m/s, the temperature distribution in the flowfield is greatly affected by the initial state.

Automated summary

This paper investigates the heat release and mass transfer characteristics in a micro power unit with dual-fuel under high environmental load. The forced-convection heat transfer in the gas flame zone is affected by the cross flow, while the rapid depressurization process results in adiabatic expansion phenomenon of the combustion-gas near the solid surface.