Material cooling rate
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Dear friends, I have a question: For a 5m3 storage tank containing water at a temperature of 90°C, with a liquid level of 60%, and the tank being insulated with aluminum silicate insulation thickness of 100mm, what will be the temperature of the water inside the tank after 1 hour?
This post was last edited by CHANGBAISHI on 2019-10-25 08:23; specification: aluminum silicate. The material specification states a thickness of 100mm, but what is the actual thickness after it’s processed? This material has a high moisture absorption rate; how should the thermal conductivity be chosen? The best insulator is a vacuum insulation layer; followed by foam insulation, high-density foam, glass wool…… The worst option would likely be this one. If calculation is to be done, the thermal conductivity of this medium needs to be provided. 5m3 is not considered large; it is recommended to consider other materials. For those with modest requirements, the best choice is a high-density glass wool compressed panel, covered with glass cloth and coated with waterproof paint. Cost-effective. For reference.
Thank you for your answer regarding heat retention. How can the cooling rate be estimated in the absence of heat retention?
It is recommended to download a reference book on Principles of Chemical Engineering, which contains relevant solutions for calculations related to heat balance, temperature, and other aspects. There are also the thermal conductivity parameters of the related insulation materials. It’s impossible to calculate without these conditions. (For reference)
Use Q=C M (90-X) to calculate the heat Q, and then use Q=k △t F to determine △t. The temperature X can be found by using the average heat transfer temperature difference; the value of K is taken as 1400 W/m2. This is the heat transfer coefficient for regular stainless steel. My opinions might be incorrect, so I welcome feedback from others
According to the \"Design Code for Insulation of Petrochemical Equipment and Piping\" (SH/T 3010-2013), the surface heat loss Q of the equipment’s insulation layer is calculated. Using the formula Q = m*Cp*(T1-T2)/t, it is possible to determine how much the temperature of the water in the tank will drop after 1 hour. Q represents the surface heat loss; m is the mass of water in the tank; Cp is the average specific heat capacity of water at temperatures between 70–90°C; T1 is the initial temperature of the water, which is 90°C; T2 is the temperature of the water in the tank after 1 hour; and t is the time taken for the temperature to drop, which is 1 hour. Pay attention to the units used in the formula.