Papers by Author: Shun Li Fang

Abstract: Trefoil-hole baffles have good thermo-hydraulic performances as the support of heat pipes, however the published research paper is relatively limited. The present paper investigates the shellside thermo-hydraulic characteristics of shell-and-tube heat exchanger with trefoil-hole baffles (THB-STHX) under turbulent flow region, and the variations of shellside Nusselt number, pressure loss and overall thermo-hydraulic performance (PEC) with Reynolds number are obtained for baffles of varied pitch with the numerical method. CFD results demonstrate that the trefoil-hole baffle could enhance the heat transfer rate of shell side effectively, and the maximal average Nusselt number is augmented by ～2.3 times that of no baffle, while average pressure loss increases by ～9.6 times. The PEC value of shell side lies in the range of 16.3 and 73.8 kPa-1, and drops with the increment of Reynolds number and the decrement of baffle pitch, which indicates that the heat exchanger with trefoil-hole baffles of larger pitch could generate better overall performance at low Reynolds number. Moreover, the contours of velocity, turbulent intensity and temperature are presented for discussions. It is found that shellside high-speed jet, intensive recirculation flow and high turbulence level could enhance the heat transfer rate effectively. Besides good performance, THB-STHXs are easily manufactured, thus promise widely applied in various industries.

Abstract: The flow of the hydrogen has played an important role in the heat exchange in the inner bell. In this research, we have studied the volume distribution of the hydrogen in the inner bell through numerical simulation method, and we get the volume distribution law of the hydrogen when we change the axial angle and the tangential angle of the velocity of the hydrogen flowing into the inner bell while we do not change the speed of the hydrogen. This research could provide theory reference for the design and application of the structure of the coil base of the high performance hydrogen bell-type annealers later.

Abstract: This paper analyzes the current energy structure and coal we use, based on clean coal technology in China, one of the current technology development status and prospects of coal were analyzed, and highlights China's Hunan province a coal for flue-cured tobacco production - biomass briquette mix, production test proved its superior performance, the desulfurization rate, burn rate of more than 90%, respectively, and 98%, suitable for promotion.

Abstract: The wet flue gas desulfurization is the main technology used today in China. Aimed the sintering gas desulfurization tower, Fluent software is used here to simulate the flow in the tower with different gas entrance angle and velocity, and we have got the effect of sintering gas entrance angle and velocity on the flow in the tower. The result shows: an appropriate increase of the gas entrance velocity and a downward inclined angle will be helpful for extending the residence time in the tower of the sintering gas and it will also improve the flow in the tower. This research could provide reference for the design and application of new wet flue sintering gas desulfurization tower later.

Abstract: During lignite pyrolysis process, there will produce large amounts of gas which is low calorific value, combustion difficult. This paper creatively put forward a program: high temperature and oxygen-containing flue gas of coal-fired mix combustion with low calorific value gas. Compared to mixing high calorific value fuel, the distinguishing feature of this program is ultra-low cost, and technically feasible. In this scheme, the stability of high-temperature and oxygen-containing flue gas is key technology. Through coal-fired experiments, we obtained generation rule of high-temperature and oxygen-containing flue gas, and summed up a diminishing marginal effect.

Abstract: The heating bell with burners is an important heating device for the high performance hydrogen bell-type annealers. The arrangement of the burners has an important impact on the heating effect. In this study, we simulated a series of model with different location of burners under the same quantity of burners and the same heating power. The result shows: (1) Under the same quantity of burners and the same heating power, when we increase the number of rows of burners, the maximum temperature inside the furnace could be reduced, and the temperature distribution will become more uniform; (2)When we fixed the number of the row of the burners, if we move the upper burners to higher position to make the arrangement of burners more uniform, the temperature distribution inside the furnace will be more uniform, this will be good for the heat transfer to the higher parts of the annealers, and this will accelerate the heating process, improve the efficiency of annealing, reduce fuel consumption, and extend the life of the inner bell.

Abstract: The flow in the burner is impacted by many factors, including the big bulk of the modern hot-blast stove, complex pipeline and too many valves. The length-width ratio of internal-combustion hot blast stoves is so high that non-uniform velocity distribution is easily brought forth along its length. Considering a real burner, a 1:5 scale model is established in this paper. The impact of the deflector on the velocity distribution of the nozzle exit is analyzed in the experiment, providing a basis for practical engineering design.

Abstract: In China, there is a vast area of tobacco producing, and the production condition in various regions is different. It is difficult for the traditional bulk tobacco curing barns with air rising to adjust the area with all conditions, and the intrinsic quality of cured tobacco is difficult to guarantee. We study on a new tobacco curing barn with double-way ventilation, and we analyze its performance through experiments. We tested the change of the temperature field in both the new tobacco curing barn with double-way ventilation and the traditional tobacco curing barn with air rising, the result shows: (1) Air moves in the new tobacco curing barn with double-way ventilation from top to bottom, compared with the traditional bulk tobacco curing barn with air rising, the new tobacco curing barn has a smaller amount of airflow, and it also has a small temperature difference on the same horizontal plane and a reasonable temperature difference on vertical direction, this is good for the curing of different maturity tobacco leaves; (2) Fuel of the new tobacco curing barn with double-way ventilation is one-time added, so the heat supply is stable, and the temperature changes quite gentle, but fuel of the traditional tobacco curing barn with air rising is many-time added, the temperature changes dramatic. (3) The new tobacco curing barn with double-way ventilation has forced ventilation channel and enhanced moisture channel to strengthen the ability of natural ventilation, so when power outages and other emergency situations happen, there is natural air convection in the tobacco curing barn, but the simple tobacco curing barn with air rising totally could not avoid the harm caused by power outages and other emergency situations. This research could provide reference for the design and application of new curing barn later.