Preparation Of Phase Change Materials Based On New Mesoporous Silicon And The Study On Thermal Insulation Effect In The Insulation Layer Of Oil Pipeline

Crude oil has the characteristics of easy solidification and high viscosity,and the fluidity decreases at low temperature.So crude oil must be transported along the pipeline at a certain temperature.However,the temperature of the heated crude oil is higher than that of the medium around the pipeline,and the crude oil will constantly dissipate heat to the outside of the pipeline during the process of transportation.Therefore,an insulation layer is usually designed outside the pipeline.At this time,the choice of insulation material is very important.High-quality insulation material can not only reduce heat loss,but also reduce the cost,and it should be safe and environmental.The phase change heat storage function of the phase change materials means that it will probably be a very effective thermal insulation material.Phase change energy storage technology has been recognized as one of the important technologies for utilizing renewable energy and saving energy.In this paper,a new composite phase change material with stable shape was prepared by vacuum impregnation method using polyethylene glycol(PEG)as phase change material and nanoflower-like wrinkled mesoporous silica(NFMS)as supporting material.The structure,morphology and thermal properties of PEG/NFMS were characterized by various testing methods.The test results showed that PEG molecules have been completely adsorbed into the pore channels of NFMS,and NFMS did not affect the crystal structure of PEG,PEG/NFMS had good thermal stability.The composite phase change material prepared in this paper has a good phase change temperature range and a high thermal enthalpy value,which has a broad application prospect in energy storage.In order to study the application effect of composite phase change materials PEG/NFMS in oil pipeline insulation,this paper is based on ANSYS thermodynamic finite element analysis.A two-dimensional model of oil pipeline was established and simulated in this paper.The thermal insulation effect of pipeline was analyzed by comparing two models with different thermal insulation materials.The simulationresults show that in the heating stage,when the insulation layer of the oil pipeline contains phase change materials,the outermost temperature of the pipeline insulation layer is lower and the heat dissipation is less.In the cooling stage,when the oil pipeline only contains ordinary insulation materials,the temperature of crude oil inside the pipeline is lower,and the temperature of insulation layer outside the pipeline is higher,resulting in more heat loss.The results show that adding the appropriate amount of phase change material into the pipeline insulation layer can reduce the heat dissipation and improve the insulation ability of the material.