Effect of main combustion zone's stoichiometric-ratio on velocity fields in the reburning zone

By probing the dynamic characteristics of the gas-particle two phase flow in reburning zones of furnaces with a Phase Doppler (PDA) instrument, rules that govern, for different stoichiometric ratios in the main combustion zone, the gas and particle velocity distribution in the recombustion zone, have been disclosed. Results show that slipping of both the gas and the particle phase gets more pronounced with increasing in the main combustion zone, and moreover that, for the 3 modes of operation investigated, slipping mainly occurs in the x direction, and that shutting of multiple adjacent primary and secondary air ports makes the main combustion zone's whirling flow avoid the jet's driving effect for quite a long run before reaching the reburning zone, so that the flow field looks like to be in a state of a natural circulation with gradually increasing radius of whirl.