The Study On Mixing Process And Effect Of Stirring In Mixer Truck

Stirrer is widely used in machinery,chemical industry,biological industry,and hasthe advantages of fast mixing speed and large reaction space.Generally speaking,the mixing operation can be divided into different types according to the different purpose of mixing,such as mixing the material,heat transfer and mass transfer.As a part of production,the mixing effect will affect the subsequent production process.Fracturing is an important part of oil exploitation in the middle and later stage of oil and gas field development,and the quality of fracturing fluid directly affects the output of oil.The configuration of fracturing fluid is mainly carried out in the mixing tank of the mixer truck,and the mixing effect will directly affect the fracturing operation.Firstly,the current research status of the internal flow field of common stirred tanks is analyzed,and the experimental research and numerical simulation methods are compared,and the advantages of the numerical simulation method are pointed out.Then,the numerical method of the flow field in the stirred tank is discussed.Among them,the standard k-e model is selected for the turbulence model,the mixture model is selected for the multiphase flow model,and the multiple reference frame method is adopted for the paddle area.The grid of the mixing tank of the mixer truck is divided by the pretreatment software ICEM CFD,and the grid area is divided into the rotary area and the static area respectively,and finally the assembly is carried out.The solid phase is composed of quartz sand and liquid phase is water.The simulation calculation is carried out by Fluent software.The velocity field and concentration field in the mixing tank of the mixer are preliminarily obtained,and the necessity of optimizing the structural parameters and operating conditions is brought out.The influence of the structure parameters(the inlet height of the inlet,the impeller immersion depth and the interval)on the velocity field and the concentration field is studied.The mixing time,the mixing power and the mixing energy of the unit volume are used to evaluate the mixing effect.At the same time,the operating conditions(sand ratio and stirring speed)are also studied on the velocity field and the concentrationfield,the above three indexes are used to evaluate the effect of the concentration field.