supermarket refrigerated showcase » article > display freezer > display cooler building graphic design (2)
display cooler building graphic design (2)
building graphic design (2)
the heat transfer calculation of the envelope structure through the envelope structure is actually the result of the combined effect of heat conduction, convective heat transfer and thermal radiation. There is solar radiation on the outer wall and the top of the display cooler, and heat conduction is mainly conducted in the envelope structure and the insulating material layer, while the air on the inner surface of the envelope structure is convective heat exchange. In order to simplify the calculation work, the heat insulation calculation of the envelope structure is calculated according to the stable heat transfer. When calculating the thickness of the insulation material, two factors need to be considered:
n9n. First, the thermal resistance of the envelope structure should be able to prevent water vapor on the surface of the envelope structure Condensation;
second, the total heat transfer of the envelope structure should be within a certain limit.
calculation of air and moisture barrier Because of the temperature difference between inside and outside of the display cooler, the partial pressure of water vapor in the air is different, and the partial pressure of water vapor in the display cooler is lower than that in the outside air The partial pressure of water vapor, so that water vapor permeation will occur. In order to facilitate the analysis, the water vapor permeation process through the display cooler enclosure structure is considered as stable conditions. For example, under stable conditions, the water vapor permeation amount P through the enclosure structure is proportional to the difference between the internal and external water vapor partial pressures of the display cooler. It is inversely proportional to the resistance encountered during the infiltration process, that is, the purpose of the air barrier and moisture-proof calculations is to check whether there is a condensation zone in the enclosure structure. If there is a condensation zone in the enclosure structure, a reasonable arrangement of the enclosure structure is required. For each layer of material, add a layer of moisture-proof material with good moisture-proof performance to ensure that the moisture inside the enclosure structure does not condense.
in actual engineering design, it is sometimes difficult to make no moisture condensation inside the enclosure. Therefore, if the designed scheme satisfies H& ge; 1.6ew, and the designed gas barrier satisfies the principles of difficult to enter and easy to exit, it is considered to meet the requirements. The so-called difficult to enter and easy to exit the principle refers to: the gas barrier layer should be arranged on the high pressure (temperature) side of the insulation structure in the enclosure structure, and the sum of water vapor permeation resistance on the high pressure side should be greater than the insulation material The sum of water vapor permeation resistance on the low pressure side makes it difficult for water vapor to enter and exit n5n for thermal insulation materials. Commonly used air and moisture-proof materials for civil display coolers include petroleum asphalt, linoleum, asphalt waterproof plastic, and polyethylene plastic film. The moisture-proof check calculation is required during design to ensure that there is no condensation in the wall. For the enclosure structure of the combined display cooler, since its surface layer is a stainless steel plate or glass steel plate with excellent moisture resistance, they are impermeable to water vapor and do not require air and moisture resistance calculations.
the above articles are from refrigerated showcase display cooler, supermarket display cooler, display cooler prices, please visit: www.ihdjx.com
free order hotline: +86 18019567573
keywords：