What should the heat transfer coefficient of the heat exchanger be?

Hehe, the conditions provided by the original poster are not sufficient to determine the heat transfer coefficient; only knowing the heat transfer coefficient can one calculate the heat transfer area! It is best to provide data on the flow rates on both sides, whether it is in gas or liquid state, the thermal conductivity of the medium, its viscosity, density, and surface tension of the liquid!

As for the flow rate, it can be assumed for now that the medium is in a liquid state； Where can I find other relevant data? Some people say it’s in the \"Chemical Process Handbook,\" but I couldn’t find it, so I’m asking for help.

The operating conditions used by the poster represent a serious waste of resources; with the temperature of the hot-side medium at 120/65°C, is it really necessary to use cryogenic brine at –19°C for cooling? If it’s designed in this way by an engineering firm, then the design quality of that firm is by far the worst in the world. It can be cooled completely using circulating water; if the heat load is high, the most energy-efficient approach is to use an air cooler for cooling. If cooling is achieved using chilled brine, on the one hand, the amount of water required for circulation in the refrigeration system will be only greater than that needed for direct cooling with circulating water; at the same time, the refrigeration unit consumes a large amount of electrical energy, and if it is a steam turbine unit, it also consumes a large amount of steam.

Thank you for the reminder from the 4th floor; I called the user again, and he said he made a mistake when filling out the order form – it should be from 120°C to 5°C.

You can go to http://bbs.hcbbs.com/thread-122096-1-3.html to take a look; it should be helpful to you.

What was said on the 4th floor is correct – it’s a bit of a waste. Even with a medium temperature of 120/5°C on the hot side, I can help you perform a calculation using HTRI if needed, but you’ll still need to provide some data such as flow rates

I’ve read many posts, and this one seems quite strange to me – everyone above seems to agree with what was said on post 4...? Regarding the use of a coolant of such high quality, I initially didn’t notice that the additional parameters mentioned by the original poster also aligned with the views expressed in post 4. However, the recommendation in post 4 to use air cooling needs to be considered carefully (there are many posts on the forum discussing this topic; there are numerous factors to take into account, and what post 4 said is too absolute). Secondly, I disagree with the conclusion in post 4 that “the consumption of chilled water exceeds that of circulating water.” When the process parameters for the heat-containing materials remain unchanged, the heat load remains constant. As for the coolant, it’s necessary to conduct an on-site analysis. Generally, the inlet temperature of circulating water is around 30 degrees Celsius, with a maximum designed temperature difference of about 8 degrees. If the ambient temperature during summer is high, say around 34 degrees Celsius at the water inlet, then in order to ensure the proper operation of the existing heat exchangers, it’s necessary to increase the flow rate of cooling water, resulting in a temperature difference of around 6 degrees. Chilled water at -19 degrees Celsius is typically used in brine-based cooling systems, where the temperature difference is between 5 and 10 degrees. If a brine-based system with a temperature difference of 10 degrees is used, the amount of water required will naturally be less. Additionally, when chilled water is used, the logarithmic temperature difference across the heat exchanger increases significantly, which in turn improves the heat transfer coefficient of the heat exchanger. Considering energy utilization, the best option is to use circulating water cooling first, followed by chilled water in series....

Heat transfer coefficient 2000 to 3000