Determining thermal and physical characteristics of wood polymer material for pipeline thermal insulation

Abstract

One of the methods for ensuring the efficiency of pipelines for transporting heat-carriers during operation is their thermal insulation, which inhibits heat transfer processes and does not affect environmental indicators. Therefore, the object of research was wood, a polymer material made by polymerization of wood sawdust and dry mixtures of synthetic resins for thermal insulation of pipelines. It has been proven that in the process of thermal action on the heat insulating layer of wood polymer material, the process of heat inhibition involves the formation of pores. This is due to the fact that the thermal conductivity of the material depends on the volumetric mass, the decrease of which for a wood polymer product leads to a decrease in thermal conductivity. In this regard, the simulation of the process of heat transfer through a cylindrical heat-insulating layer made of wood of polymer material was carried out and the dependences derived, which allow obtaining a change in the dynamics of heat transfer and determining thermophysical properties. According to the experimental data and the established dependences, it was found that the thermal conductivity of the wood of the polymer material was within 2.4÷2.9·10-8 m2/s, the thermal conductivity of the sample did not exceed 0.030 W/(m∙K). In addition, the heat capacity of the product corresponds to a value of more than 1034÷1145 kJ/(kg·K) depending on the thickness, which accordingly categorizes it as a heat-insulating material. At the same time, data on thermal insulation properties for polyurethane foam show that when it is used with a density of 100 kg/m3, the thermal conductivity is 0.029 W/(m∙K), which is approximately the same as the value of the proposed wood polymer material. The practical value is the fact that the results of determining the heat-insulating properties of a wood polymer material make it possible to establish the scope and conditions of its application