Accession Number : ADP009042

Title :   Solid Fuel Combustion in a Forced, Turbulent, Flat Plate Flow,

Corporate Author : CALIFORNIA UNIV BERKELEY DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Zhou, L. ; Fernandez-Pello, A. C.

Report Date : 23 JUL 1992

Pagination or Media Count : 4

Abstract : An experimental study is conducted of the effect of flow velocity, grid-generated turbulence and buoyancy on the combustion of a solid fuel in a flat plate boundary layer flow. The effect of buoyancy is determined by comparing the surface regression rates, flame characteristics, and exhaust products composition for the solid burning in a flow and ceiling orientation. Measurements are presented for the ceiling surface regression rate of PMMA sheets burning in air, and compared with previously obtained floor data. It is concluded that buoyancy has two major, and counteracting, effects. One is to affect the heat transfer by shifting the flame away from the surface in the floor burning and closer to the surface in the ceiling. The other is also due to the flame shifting and the instabilities associated with it that favors, in the floor case, the mixing of the reactants, and consequently the overall heat release rate. In the ceiling, the proximity of the flame to the cold surface causes quenching of the reaction, and the stability of the flame hampers reactants mixing, both of which reduce the heat generation rate. The overall result of these two counteracting mechanisms is that the surface regression rates are not that different in both geometries, although the composition of the combustion products are quite different

Descriptors :   *COMBUSTION, *FUEL CONSUMPTION, *FLAME PROPAGATION, *SOLID FUELS, TURBULENT FLOW, BOUNDARY LAYER FLOW, GAS SURFACE INTERACTIONS, FUEL AIR RATIO, HEAT TRANSFER, SURFACE ANALYSIS, REGRESSION ANALYSIS, BURNING RATE, CEILING, FLOORS, BUOYANCY, CARBON MONOXIDE, MASS TRANSFER, COMPARISON.

Subject Categories : Combustion and Ignition
      Fuels
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE