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Benchmark Database for Input and Validation of Multiphase Combustion Models.


pdf icon Benchmark Database for Input and Validation of Multiphase Combustion Models. (261 K)
Widmann, J. F.; Charagundla, S. R.; Presser, C.

Chemical and Physical Processes. Combustion Institute/Eastern States Section. Proceedings. October 11-13, 1999, Raleigh, NC, 1999.

Keywords:

combustion models; databases; validation; interferometry

Abstract:

Control of process efficiency and the formation of species byproducts from industrial thermal oxidation systems (e.g., power generation and treatment of liquid chemical wastes), is generally based on a priori knowledge of the input stream physical and chemical properties, desired stoichiometric conditions, and monitoring of a few major chemical species in the exhaust. Optimization of the performance of these systems is relying increasingly on computational models and simulations that help provide relevant process information in a cost-effective manner. Although computational fluid dynamics (CFD) offers a cost-effective alternative to experiments, the accuracy of the CFD model must first be assured. This should be accomplished in two ways: verification and validation, Verification involves, ensuring that the algebraic and differential equations within the model have been accurately solved. In addition to verifying that the numerical code arrives at the correct solution, it is also necessary to determine if the chosen model accurately represents the physical process of interest. This is the validation step. The objective of this paper is to provide benchmark experimental data for CFD model and submodel validation. This paper presents data obtained from a baseline spray flame within the reference spray combustion facility at NIST. The spray data presented were collected non-intrusively using phase Doppler interferometry (PDI). The size and velocity distributions of the fuel droplets, droplet number density, and volume flux of fuel droplets within the spray have been obtained. The enclosed combustion chamber provides well-characterized boundary conditions, and wall and ceiling temperature profiles have been measured. Gas temperature and species measurements obtained at the reactor exit can be used for boundary conditions or validation of computational results. The inlet combustion air has been characterized using a 3-D CFD simulation to determine the velocity and turbulence intensity profiles, and the simulation has been validated with experimental data. Gas-phase velocity, temperature, and heat flux measurements are planned for completing this baseline case.