heat transfer coefficient
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Recently, I have been helping to design a reactor, with the reaction system being calculated based on water. It is assumed that 40 kg of hydrogen peroxide is added to 1 ton of water; hydrogen peroxide decomposes during the reaction, releasing heat in the process. The leader told me that the reactor is cooled by exchanging heat with air. I want to figure out how to determine the heat transfer coefficient for heat transfer with air
This post was last edited by wiseboy on 2011-4-27 10:07. Your question is completely unfocused and unprofessional; it’s a mess. You want to ask about the “load capacity of the vehicle”; you should also specify whether it’s a train Truck? It’s still a small bridge vehicle. :Handshake, is that how your boss wants questions to be posed?
Oh, maybe I was a bit vague in my wording. I just want to know: for a stainless steel reactor in which the reaction fluid is water, and cooling is to be achieved directly through air, isn’t it necessary to know the heat transfer coefficient in order to determine the heat exchange rate? I wonder how to calculate the heat transfer coefficient with air.
First, assume the heat transfer coefficient K1; later, compare it with the calculation coefficient K2. If K2/K1 is between 1.15 and 1.25, then the heat transfer coefficient can be used. Otherwise, further assumptions and calculations are needed until the conditions are met.
This post was last edited by wiseboy on 2011-5-9 13:49. Is the liquid level of the reactor in direct contact with the atmosphere? To what height inside the reactor has the liquid level been filled? How far is it from the upper edge? Is the reactor indoors or outdoors? Is the reactor equipped with stirring? Is the reaction solution as thin as plain water or is it viscous? What is the viscosity? Is the reaction solution as heavy as plain water or less dense? What is the density? . . . . . ? ? ? Really, the way you ask questions is like that of a CIA agent who is hesitant to speak, rather than someone with a technical background. Heat transfer calculations seem very simple for you; no one can assist you with the conditions you provide.
I’m not sure how to put it. Could you be more specific?
I guess the original poster is looking for an approximate value, but the question is too vague. Most importantly, the heat transfer coefficient is related to the temperature difference with the environment as well as the size of the reactor. I can give you some empirical values: Capacity, heat transfer coefficient (W•(kg•K)-1): 2.5 m3 – 0.054; 5 m3 – 0.027; 12.7 m3 – 0.020; 25 m3 – 0.005. For volumes of 10 ml, the value is 5.91, and for 100 ml it’s 3.68. You can do the calculations yourself; keep in mind that the temperature difference between the inside and outside is 60 K, and the filling efficiency is 80%.