| As a traditional ethnic therapy,sand burial therapy has a long history and a lot of medical research in turpan,xinjiang.This therapy has remarkable effects on various chronic diseases,such as arthritis,waist and leg pain,etc.,so it attracts a large number of patients and tourists who are in need of treatment and experience.Buried sand treatment of natural sand therapy was initially in turpan area,because the turpan region of the sand contains minerals and trace elements are relatively high,and the summer light during the day time is long,the climate is dry little rain,sand temperature is relatively constant,but due to the site,seasons and environment,and many other factors,can only be from may to August will open to public.Then,the method of imitating the natural sand therapy place through the indoor four-season sand therapy room was derived.Although the limitation of season and region was solved,the investment of construction cost was increased,and the limitation of inconvenience and immobility was also found.Therefore,it is particularly important to design a sand-blasting medical rehabilitation device that combines sand therapy with traditional Chinese acupuncture,which is not only convenient for treatment,but also not affected by external factors such as climate,region and time.The device will use air compressor in the sand can sand to particular pipe pressure,the sand flows through the internal pipe with constant temperature heat source,and uniform sand heated and regulating system through a device at the end of the nozzle,the grains of sand with moderate strength,a certain temperature and uniform sediment injection to the corresponding parts of the body,out of sand grains with heat,can make the local tissue vasodilation,blood and lymph circulation,so as to relieve pain and to achieve the effect of rehabilitation.The sandblasting device occupies a smaller area and is free and flexible compared with the indoor four-season sand-treatment room,which can break the limitation of treatment only in specific places.This article mainly by the gas-solid two phase flow sandblasting device of heating system as the research object,the heating system is mainly composed of external pipe and the inner heat source,using the principle of heat transfer and fluid dynamics,adopt the method of numerical simulation to study effect of the heating system in sand heated,analysis of different heat source structure,the working pressure and particle diameter of sand grains in the basin is the influence of the heat transfer efficiency.Objective: to obtain the optimal heating structure,inlet working pressure,suitable particle diameter and sand output,and to determine the optimal scheme of heating system,so as to provide the basis and data support for specific experiments.Firstly,three dimensional physical models of four different heat source shapes were designed,and the DO radiation model,Boussinesq hypothesis and standard k-ε equation were used to calculate the gas-solid coupling problem in the heating system by finite volume method.The temperature field changes of each heat source shape are simulated respectively.The results show that when the internal heat source is a solid cylinder,the heat of the particles is relatively uniform,and the proportion of incoming and outgoing sand in the pipeline is high.Secondly,after determining the shape of the internal heat source,five working pressures between 0.2MPa and 0.6MPa were changed to study the heating of sand grains.It was found that the heating temperature of sand grains in the pipeline was the best when the working pressure was 0.2MPa.Cylinder in the shape of the internal heat source(solid)and pressure(0.2 MPa)are sure good cases,by setting up three different particle diameter:1.5mm,2mm and 2.5mm to study of sand heated,according to the comparison of simulation results,found that when the particle diameter is 2mm,best heat effect of sand,and conform to the required temperature range.Finally,in the shape of the internal heat source(solid cylinders),pressure(0.2MPa)and particle diameter(2mm)to determine the good situation,including heat source for solid cylindrical shape,on the basis of the heating system of four kinds of optimization design of the model,based on the model of temperature field,velocity field,the quantity of sand particle trajectories,and comparison of energy consumption as well as considering the sand flow in heating system of heat loss,finally selected the inner heat source for five solid cylindrical structure as a numerical simulation of the optimal solution,for the specific experiment provides the reliable theory basis and data support. |
