Study On Effective Thermophysical Properties Of Phase Change Capsule Composites Based On Micromechanics

In order to rationally develop the rich oil resources on the seafloor,ensuring the fluidity of the oil and gas pipelines on the seafloor is an important part of the oil and gas extraction process.During the transportation of oil and gas in marine pipelines,the low temperature environment will precipitate wax crystals and form hydrates in the pipeline to block the pipeline.The importance of pipeline insulation is self-evident.The traditional submarine pipeline insulation technology has the disadvantages of high cost,environmental protection,and complicated structure.This paper proposes a new composite insulation structure filled with phase change microcapsules in the insulation layer.The phase change process realizes the storage and release of energy.The effect of automatic insulation of the pipeline insulation layer according to the temperature in the pipeline is achieved.As a high-density,many kinds of materials,diverse characteristics,and excellent energy storage materials,phase change materials can store and release energy through phase change reactions,and realize different forms of energy conversion by controlling the phase change direction.However,in the actual application process,the general thermal conductivity of phase change materials is low,and there is a large volume difference before and after the phase change,which has a great impact on the structural performance of the insulation layer.In severe cases,it may even cause the insulation layer to crack and change Issues such as material leakage.Therefore,it is of great significance to study the phase change microcapsule technology which has a certain coating property on the phase change material and can greatly improve the heat transfer efficiency of the phase change material.In this paper,the composite material model is built with the help of COMSOL,DIGIMAT and other software.The microstructure of the composite material is analyzed using mesomechanics.The macroscopic thermal conductivity of the composite material is predicted by studying the microstructure and thermal conductivity of the composite material.Starting with the thermophysical parameters on the micro-scale of the phase change composites,the density,specific heat capacity,thermal conductivity and other parameters are investigated,and the factors and mechanisms that affect the changes of these parameters are clearly defined.By changing the volume fraction,diameter,shape and other parameters of the phase change microcapsules in the composite material,adjusting the macroscopic thermal conductivity,heat storage,temperature control range,heat transfer efficiency and other properties of the composite material,it can be designed for production for various purposes and occasions Applied phase change capsule composite material.It is of great significance to deeply study the microscopic thermal properties of phase change microcapsule composite materials,and to provide design models and theoretical basis for the practical application of the new composite insulation structure containing phase change microcapsules.