Transient Catalytic Combustion.
Abstract
Results of an experimental study of the catalytic ignition of lean propane-air mixtures on platinum in a stacked-plate catalytic combustor are presented. The effects of inlet temperature, equivalence ratio and gas velocity on the ignition transient were investigated. The ignition process was characterized in terms of the substrate axial temperature profile and the exhaust gas CO and CO2 concentrations measured as a function of time after the fuel was turned on. Ignition was always found to occur first near the leading edge of the catalyst as indicated by the more rapid heat-up of the front end of the catalyst. The downstream end of the catalyst heated up more slowly and was strongly dependent on convective heat transfer from the front of the catalyst. Increased inlet temperature, equivalence ratio and velocity were all found to shorten the ignition transient and to lead to increased steady state peak substrate temperatures. increased velocity also caused the peak substrate temperature to move further toward the back of the catalyst. For the conditions studied, the initial ignition rate was found to be surface reaction rate controlled at higher velocities (above 2 m/s) but at lower velocities (below 2 m/s) the initial ignition rate was found to depend both on the surface reaction rate and the mass transport rate. The transient ignition measurements also clearly revealed the fact that complete conversion can be achieved by substrate temperatures which are several hundred degrees below steady state. Keywords: Catalytic combustion, Catalytic ignition, and Premixed turbulent combustion.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 10, 1986
- Accession Number
- ADA173098
Entities
People
- D. A. Santavicca
Organizations
- Pennsylvania State University