Development of combustion dynamics at thermochemical conversion of biomass pellets

Experimental study of combustion dynamics was aimed to provide control and analysis of the main effects determining the development of swirling flow dynamics at thermo chemical conversion of biomass pellets (wood and wheat straw). The presented experimental study is carried out in a batch-size experimental device with a heat output up to 2 kW along with test experiments in a pilot device with a continuous supply of biomass pellets and a heat output up to 20 kW. The experimental study of combustion dynamics includes the time-dependent measurements of the main flame characteristics at thermo-chemical conversion of biomass pellets, which involve complex measurements of the swirling flow velocity, temperature and composition fields' formation, along with estimation of main factors, affecting the development of combustion dynamics and a heat energy production. Considering the upstream and downstream swirl flow effects on the formation of the flame reaction zone it is shown that the swirling air flow can be used as an effective tool to enhance the mixing of the axial flow of volatiles with an air swirl and the enhanced thermo chemical conversion of renewable fuels - biomass pellets of different elemental and chemical composition (wood and wheat straw).