There is heat transfer between any object. Today we want to talk about the heat transfer in the refractory material of ceramic fiber blanket.
Heat transfer is a complex phenomenon. It is often divided into three basic modes: heat conduction, heat convection and heat radiation.
The thermal conductivity of ceramic fiber blanket decreases with the increase of bulk density, but if the decrease is small, the thermal conductivity will increase when the density exceeds a certain range. At different temperatures, the minimum thermal conductivity corresponds to the minimum bulk density, and the bulk density corresponding to the minimum thermal conductivity increases with the increase of temperature.
The above is of great significance to the application of ceramic fiber blanket. The thermal insulation performance of ceramic fiber is to use the thermal insulation effect of closed air in the pores of products. When the solid fiber reaches a certain proportion, the porosity increases and the bulk density decreases.
When the slag ball content reaches a certain proportion, the influence of bulk density on the thermal conductivity VB coefficient actually refers to the influence of porosity, pore size and pore properties on the thermal conductivity. When the bulk density is less than 96kg / m3, due to the enhancement of oscillating convection and radiation heat transfer of gas in the mixed structure, the thermal conductivity decreases with the bulk density and increases exponentially. When the bulk density is greater than 96kg / m3, when the bulk density increases, the pores in the fiber are closed, and the microporous shape increases. The air flow in the pores is limited to a certain extent, and the heat transfer in the fiber is reduced (the thermal resistance increases). At the same time, the radiant heat transfer through the hole wall is reduced, resulting in the reduction of thermal conductivity.
When the bulk density increases to a certain range of 240 ~ 320kg / m3, the solid fiber contact point increases, and the solid fiber contact point increases, which weakens the resistance of pores to heat transfer, resulting in the thermal conductivity no longer decreasing and will increase.
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Shandong redon high temperature materials Co., Ltd. has domestic high-end production equipment and reliable production technology, with an annual output of 1050 ceramic fiber series products, 1260 ceramic fiber series products, 1400 ceramic fiber series products and 1600 polycrystalline series products of more than 10000 tons. There are more than 30 kinds of products in different forms, such as cotton, blanket, felt, board, paper, various textiles, profiled products, modules, folding blocks, castables, spraying and so on, which can meet the heat insulation requirements of different situations in the high temperature field. Welcome to click the online service at the bottom right of the website or submit an online inquiry. We will contact you as soon as possible.