What material should be used for supporting the low thermal conductivity materials in a 400-degree jacket? ? ?
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Recently, I came across a project that required the creation of jacketed tubes, with a gas at 400 degrees Celsius flowing inside the inner tube. The jacketing was needed to have a low thermal conductivity (below 0.35 W/M·K) and to be able to withstand a compression force of 6 MPa. I would like to ask what material would be better? I tend to use ceramics, but their thermal conductivity is too high. Are there any ceramics with low thermal conductivity? It would be great if you could recommend some manufacturers
It’s not easy to understand. A jacket is added for heat exchange; then why is it necessary to prevent heat conduction? Is it normal for the jacket to be empty, with material only being introduced under special circumstances (such as for cooling)?
This post was last edited by niuzhejun on 2016-7-13 at 16:30. A jacket is used for insulation, with the aim of preventing heat from the inner tube from escaping to the outer tube. At present, the three elements of heat transfer—convection and radiation—can be controlled; however, no suitable material with low thermal conductivity has been found for this purpose. High-temperature gas flows only inside the inner tube
The main challenge lies in achieving low thermal conductivity, while also being able to withstand a pressure of 6.4 MPa; the components are not large, with tube supports having a diameter of only 150 millimeters
The current problem for the poster is that the inner tube and the outer sleeve experience heat bridge heat transfer due to the jacket supports, and this is indeed quite tricky to deal with. Doesn’t the original poster work on vacuum-insulated tubes? How many degrees can such tubes retain heat for a given medium?
This post was last edited by niuzhejun on 2016-7-19 at 10:22. Currently, vacuum insulation is used in pipelines for low-temperature media such as liquid nitrogen and liquefied natural gas. It is hardly used in high-temperature applications, or maybe I am just not aware of any such cases. . . Materials that can be used at low temperatures cannot be used at high temperatures; processes such as evacuation and multi-layer insulation also change completely. Therefore, it is still in the research and development stage. If successful, such pipes could have market value only if they can achieve a heat loss of around 0.5W.