| With the large capacity,high load thermal power units successively put into operation,as an auxiliary machine pneumatic conveying system is facing increasing load pressure,in order to achieve the coal ash pneumatic conveying process of greening,stabilization,energy saving goals,the optimization of the pneumatic conveying system is imperative.Pilot pneumatic conveying technology is applied in this context,this technology is mainly added to the main intake pipe "replenishment" device,dredging the particles in the ash pipeline,achieving the purpose of long-distance solar saving,and this topic,mainly based on this technology as a reference,achieves the purpose of solar saving by/through adding auxiliary intake pipe to horizontal tube.The main tasks are as follows:In this paper,Computational Particle Fluid Dynamics（CPFD）method is mainly used to perform numerical simulation analysis on horizontal tubes with a diameter of 125 mm and a length of 10 m.First of all,based on the orthogonal mesh included in barracuda software,the horizontal tube is grid-independent verification and the grid of 500000 can provide a reliable guarantee for the subsequent simulation analysis results.The interaction between the main intake velocity of the main horizontal tube and the mass flow rate of the particles is analyzed.The relationship between the formation of deposit layers of pulverized coal particles in the deposition process of horizontal tubes and the main intake gas velocity and particle mass flow rate were studied.Reducing the intake velocity or increasing the particle mass flow rate increases the thickness of the particle deposit layer.After that,an auxiliary intake tube is added to the horizontal tube to compare the dredging effect of the particles before and after the addition of the auxiliary intake tube.The results show that the increase of the intake rate,the better the dredging effect on the particle accumulation layer.When the tilt angle of the auxiliary intake air changes from 35° to 55°,the dredging effect on the particle accumulation layer first becomes better and worse,and the dredging effect takes its peak at about 45°.The working time of the particles in the tube is t,and the energy consumption loss of the particles in the tube is the power consumption coefficient E.Determine the three structural parameter factors of auxiliary intake（intake speed,tilt angle,distance between adjacent two valves）,two target values（working time t,power consumption coefficient E）for one-factor climbing test,analyze the change trend of the two target values with the three factors,and analyze the optimal values of the two targets,the research results show that the relationship between the structural parameters and the target values is complex,interrelated and mutually restrictive,within a certain range,The changes in the structural parameters of the auxiliary intake pipe have different influences on the energy consumption characteristics of the pneumatic conveying process,and in order to achieve the energy saving of the pneumatic conveying system,it is necessary to consider the influence of the structural parameters of the auxiliary intake pipe in a balanced manner.The response surface method is used to design and carry out multiple sets of center experiments,and an approximate model is built with the working time t and power consumption coefficient E as the goals,and the multi-objective optimization of the structural parameters of the auxiliary intake pipe is carried out based on the approximate model of two target values.After optimization,it is found that the auxiliary intake speed is 5m/s,the intake angle is 45°,the distance between the adjacent valves is 1900 mm,and the particle dredging effect is better.Compared with the same main intake speed,and feed flow rate without auxiliary intake,it is found that the working time is shortened by 4.97% after the addition of auxiliary intake,while the power consumption coefficient is reduced by 33.51%. |
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