Catalytic Combustion

Catalytic Combustion and Catalytically Stabilized Combustion – Numerical Studies of the Thermal and Chemical Behavior of Catalytic Combustion on Monolith Supported Catalysts

Faculty:
Prof. Robert Dibble, Department of Mechanical Engineering, University of California
Prof. Andr‚ Boehman, Department of Energy & Geo-Environmental Engineering

Objective:
To understand the impact of the level of unmixedness on emissions formation during catalytically stabilized combustion.

Approach:
Prof. Dibble’s group has performed experimental studies of the effect of unmixedness on hybrid combustor behavior. In collaboration with Prof. Dibble’s group, a model has been constructed that considers the effect of the monolith supported catalyst on a fuel-air mixture with temporal (time varying) unmixedness but spatial (radial) uniformity of composition and the subsequent behavior of the gas phase combustion zone downstream of the monolith. The combined model (monolith + PFR) is used to predict overall NOx formation across the hybrid combustor.

Results:
To date, the simulations are only partly successful. As shown below, the uncatalyzed combustion calculations match the experimental observations quite well. But, for the catalytically stabilized combustion, the agreement is not as good.

Publications:

Boehman, A. L. and R. W. Dibble. Experimental and Numerical Investigation on the Influence of Temporal Fuel/Air Unmixedness on NOx Emissions of Lean Premixed Catalytically Stabilized and Non-Catalytic Combustion. Catalysis Today, 59, 131-140 (2000).

Catalytic Combustion (1)

Comparison of Predicted and Measured NOx emissions for Uncatalyzed Combustion of Propane

Catalytic Combustion (2)

Comparison of Predicted and Measured NOx emissions for Catalytically Stabilized Combustion of Propane