Spouted pressure drop was one of important parameters in the design and application of spouted bed.In this paper spouted pressure drop of a new double nozzle rectangular draft tube spouted bed was studied.A 120 mm...Spouted pressure drop was one of important parameters in the design and application of spouted bed.In this paper spouted pressure drop of a new double nozzle rectangular draft tube spouted bed was studied.A 120 mm×240 mm cross section double nozzle rectangular stainless steel spouted bed was used to investigate the effects of flow rate,particle diameter,bed height,draft tube diameter and height of entrainment zone on maximum spouted pressure drop.Maximum spouted pressure drop increased with increasing flow rate, increasing particle diameter and increasing height of entrainment zone.Maximum spouted pressure drop increased and then decreased with increasing draft tube diameter.Maximum spouted pressure drop was hardly affected by bed height.By regression of experimental data,the correlation of maximum spouted pressure drop with the above parameters was obtained.展开更多
In a rectangular fluidized bed combustor, the tracer gas is injected continuously into the bed from a point source at the center of the distributor plate. In this study, a general governing equation is formulated for ...In a rectangular fluidized bed combustor, the tracer gas is injected continuously into the bed from a point source at the center of the distributor plate. In this study, a general governing equation is formulated for tracer gas dispersion in the bed. An analytical solution is derived to estimate the dispersion coefficients, Dxand Dy, in a horizontal plane. The concentration profiles at different sampling heights with various gas velocities are plotted.Subsequently, to estimate the dispersion coefficients, surface fitting of the obtained analytical solution to the experimental data is performed. The dispersion coefficients obtained from this model are compared with those of a conventional model. Additionally, the effect of walls, bed height and gas injection rate on the dispersion coefficients in a horizontal plane is investigated, and the effect of distributor design on the dispersion coefficients in a horizontal plane is investigated with different tracer positions. It is found that Dxand Dyare nearly equivalent at a lower tracer gas ratio of the injected gas to the total gas flow rate. It is also demonstrated that the effect of bed height on Dxis minor. This model is also able to estimate the dispersion coefficients in the case of a multihorizontal nozzle distributor.展开更多
文摘Spouted pressure drop was one of important parameters in the design and application of spouted bed.In this paper spouted pressure drop of a new double nozzle rectangular draft tube spouted bed was studied.A 120 mm×240 mm cross section double nozzle rectangular stainless steel spouted bed was used to investigate the effects of flow rate,particle diameter,bed height,draft tube diameter and height of entrainment zone on maximum spouted pressure drop.Maximum spouted pressure drop increased with increasing flow rate, increasing particle diameter and increasing height of entrainment zone.Maximum spouted pressure drop increased and then decreased with increasing draft tube diameter.Maximum spouted pressure drop was hardly affected by bed height.By regression of experimental data,the correlation of maximum spouted pressure drop with the above parameters was obtained.
基金The financial support from the Ministry of Science and Technology under Grant MOST 105-3113-E-033-001
文摘In a rectangular fluidized bed combustor, the tracer gas is injected continuously into the bed from a point source at the center of the distributor plate. In this study, a general governing equation is formulated for tracer gas dispersion in the bed. An analytical solution is derived to estimate the dispersion coefficients, Dxand Dy, in a horizontal plane. The concentration profiles at different sampling heights with various gas velocities are plotted.Subsequently, to estimate the dispersion coefficients, surface fitting of the obtained analytical solution to the experimental data is performed. The dispersion coefficients obtained from this model are compared with those of a conventional model. Additionally, the effect of walls, bed height and gas injection rate on the dispersion coefficients in a horizontal plane is investigated, and the effect of distributor design on the dispersion coefficients in a horizontal plane is investigated with different tracer positions. It is found that Dxand Dyare nearly equivalent at a lower tracer gas ratio of the injected gas to the total gas flow rate. It is also demonstrated that the effect of bed height on Dxis minor. This model is also able to estimate the dispersion coefficients in the case of a multihorizontal nozzle distributor.
