Analysis Of Heating Factors On Aggregate In The Rotary Dryer Of Asphalt Mixing Equipment

The main body of rotary dryer in asphalt mixing plant is revolving drum with small slope,and always equipped with flights、a feed box、a discharging box and a driving device, and iskind of device that is heated by very high temperature and can transport material, and it iswidely used. Firstly, In this paper, using the analysis method for summarizing the factorswhich impact on heat transferring to aggregate and it will be divided into two broad categoriesof factors.(1) The factors which influence the heat transfer efficiency between gas andaggregate.(2) The factors which impact on temperature stability of aggregate. Secondly, thepaper mainly focus on two points of these two categories of factors, the first point is thattemperature stability is affected by pressure fluctuations and the second point is that theparameter of flights will impact on the heat transfer efficiency of the dryer. by means ofestablishing the numerical heat transfer model of aggregate particles in the rotary dryer(Thismodel is established by some parts: Non-premixed combustion model,heat convection modelbetween gas and aggregate particles, Radiation model between aggregate and flame.) andusing FLUENT software to simulate how will the temperature fluctuate in the situations thatthe pressure fluctuates, and simulated results is satisfactory. The simulation of heat transferefficiency between gas and aggregate is simulated with three steps, firstly Takingconcentration in the cross-section of the rotary dryer as a parameter in the numerical heartransfer model and then using MATLAB PDEtool to simulate in some kinds of differentconditions, thirdly compare the results which in some kinds of different conditions. Theresults show that the L-type flights with90°installation angle is the best choice for increasethe efficiency of the convection between gas and aggregate.