Combined Convective-Radiative Heat Transfer Enhancement in an Advanced Gas-FiredSurface Combustor-Heater. Annual Report, March 1990-February 1991

摘要

The research program is directed toward obtaining a fundamental understanding ofcombined convective-radiative heat transfer that interacts with combustion in a surface combustor-heater. In Task 1, Experimental Study, the bench-scale surface combustor-heater unit (200,000 Btu/h firing rate) with associated operation, control, and data acquisition and analysis systems has been prepared. The parametric studies on the effects of the major configurations of the heat-exchanger tubes, as well as materials of construction of the porous matrix on the performance of the test unit have been conducted. Data demonstrated the excellent performance of the test surface combustor-heater: high heat-transfer rates up to 100,000 Btu/h-sq ft and combustion emissions for both NO(x) and CO as low as 15 ppm over a practical operating range. In Task 2, Analytical Study, the development of a two-dimensional time-dependent mathematical model of the surface combustor-heater has been accomplished.