Radiation Model for Flows in High-Pressure Arc Heaters
Abstract
Analytical solutions of the integral equation of energy transport have so far been limited to a few simple geometries, one of which is the field with cylindrical symmetry - a good match with the geometry of modern high-pressure arc heaters, provided the electric discharge remains on the centerline of the heater. Unfortunately, it is known that the arc column in such devices undergoes substantial excursions from the centerline a large part of the time. To deal with the resulting strong asymmetries in temperature, the radiation transport was modeled using the differential (diffusion) approximation. This results in a partial differential equation which can be solved in multiple dimensions by the same methods that are used to solve the gasdynamic equations. The method has been verified by duplicating the one-dimensional formal integration results. Analysis of behavior of very hot gases requires the modification of the equations of motion by the addition of a radiant energy transfer term to the conservation of energy. Transport of radiant energy in a region of hot gas is described by the spatial and directional variation of the spectral radiation intensity function. This function is defined as the rate of flow of radiant energy of frequency v in the direction of the unit vector at a point specified per unit solid angle increment about the direction of propagation, and per unit increment of photon frequency about v. The spatial variation of Iv in a given direction is described by the radiative transfer equation (RTE) for a nonscattering gas.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1992
- Accession Number
- ADA246295
Entities
People
- E. J. Felderman
- W. N. Macdermott