thesis

thesis

Analyzing producergas in a counterflow setup

Biomass is a natural substance, which accumulates solar energy as chemical energy by the process of photosynthesis in the presence of sunlight. Biomass chiefly contains cellulose, hemi-cellulose and lignin, having an average composition of C6H10O5, with slight variations. For the complete combustion of biomass the theoretically amount of air required (defined as the stoichiometric quantity) is 6 to 6.5 kg of air per kg of biomass and the end products are CO2 and H2O. In gasification, biomass is subjected to partial pyrolysis under sub-stoichiometric conditions with the air quantity being limited to 1.5 - 1.8 kg of air per kg of biomass. The resultant mixture of gases generated during the gasification process is called producer gas, contains CO and H2 and is combustible. The raw producer gas also contains tar and particulate matter which have to be removed as they are harmful to the engine. source: http://www.desipower.com/technology/biomass.htm
The thesis main goal is to research producergas flames in a counterflow burner setup.. These phenomena are key discriminators to rate the performance of chemical models. Such a counter-flow burner is made up of two opposing ducts. In the case of non-premixed flames fuel and nitrogen will be injected from one duct opposed by an oxidizer stream made up of air. In the premixed configuration the reactive stream consisting out of fuel, oxygen and nitrogen is injected from one duct, and nitrogen is injected from the other duct. Flow-rates are measured to calculate the velocities of the reactant streams at the injection plane. The strain rate can be determined out of the velocity data of the fuel stream. Temperature is measured by using thermocouples. Extinction and auto-ignition characteristics of the fuels will be measured. The data will be compared with numerical data obtained out of a combustion model using detailed chemistry at conditions of the experiments. The numerical results are obtained with the 1D flame code CHEM1D which was developed at the TU/e and the FlameMaster code developed at Stanford University.