Simulation Analysis Of Influencing Factors Of Infrared And Hot Air Synergistic Heating Asphalt Pavement

At present,different heating methods of asphalt pavement in hot in-place recycling equipment show different advantages and disadvantages.The infrared radiation heating method is highly efficient,but it leads to aging and carbonization of asphalt.Hot air circulation heating possesses many advantages in heating uniformity and small temperature gradient.However,the heating rate is low and the time taken in HIR is long.Therefore,in order to find a new heating method that can fuse the advantages of different heating methods and reduce the impact of its shortcomings on the heating effect of asphalt pavement,it is necessary to study the heat transfer law of the heating method under the influence of multi-factor coupling and the thermal regeneration process of asphalt pavement.In this paper,after comparing the advantages and disadvantages of several current mainstream thermal regeneration methods,the heating method combining infrared heating and hot air circulation heating is selected as the heating method of the simulation experiment.And using the new method to carry out multiple simulation experiments,the working condition with better heating effect is combined with the influencing factors,and the working conditions with good heating effect were combined with the influencing factors.At the same time,through the data analysis of the simulation results,the heat transfer law of the thermal regeneration process of asphalt pavement was studied.(1)Reasonably plan the parameter range of the simulation model and establish a physical model of multiple cooperatively heated asphalt pavements.Various types of heating methods have been designed to incorporate various factors that affect the heating effect.The FlUENT finite element analysis software simulation experiment was used to solve the problem.(2)Comparing the simulation results of each group by the control variable method,the final heating distance is 5cm,the hot air circulation wind speed is 3m/s,and the heating mode is second.(The ratio of infrared radiation to hot air circulation on time is 3:2)The asphalt pavement has the best heating effect.(3)The relationship between the distance from the surface layer of the pavement and the temperature setting is analyzed when the temperature of a certain part of the asphalt pavementchanges to a certain temperature under the influence of different influencing factors.At the same time,the influence of different influencing factors on the temperature increase at different depths of asphalt pavement is analyzed.(4)By referring to the new method of heating the asphalt pavement in the patent,a new heating model of the temperature field of the three-dimensional asphalt pavement was established,and the heating method was selected to heat it.According to the simulation experiment results,the heating characteristics of different models are obtained,and the heating effect is compared to obtain the selection criteria of the shape of the dowel in the new method under different working conditions.