Help post: Heat exchanger time
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How much steam is required and how long will it take for a 120 square meter shell-and-tube heat exchanger to raise water at 55 degrees Celsius to 85 degrees Celsius using steam at 100 degrees Celsius?
There are many small programs for heat exchanger calculations available on the forum that you can download; you can search for them on your own.
The steam volume is calculated based on thermal equilibrium, and then a heat loss rate is added to obtain the required amount of steam. The flow rate of the medium inside the heat exchange tubes is related to the heat exchange structure, the medium itself, the heat transfer coefficient, and the material used for heat exchange. In the design of heat exchangers, it is necessary to control the flow rate of the medium within them; this flow rate exists within a certain range, and the heat exchanger must not operate outside of these limits, whether under maximum or minimum operating conditions. Based on the flow rate inside the heat exchange tubes, it is possible to calculate the time it takes for the medium to move from entering the heat exchanger to exiting it – this time is known as the heat exchange time.
There’s no traffic at all. Heat exchange is a continuous process; what do you mean by time?
There is no flow on the cold side, so it’s impossible to make a calculation. Once the area of the heat exchanger is known, it’s necessary to work backwards to determine the time required. Generally, the temperature needs to be raised within a specified time frame as requested by the customer, and based on that, the area of the heat exchanger can be calculated. You are now deducing the time based on area, which is theoretically feasible. Hahaha, it’s the same as not saying anything
I heard about the heat exchange time for the first time, hahahahahaha
Assuming an infinite supply of heat, the flow rate of the cold source is unknown, as is the outlet temperature of the heat source (i.e., the temperature acceptable to the user). To achieve a fast heat exchange rate (i.e., in less time), it is necessary to have a larger temperature difference between the two sides; ideally, the heat source should have steam at 100°C on the inlet side and a gas-liquid mixture at 100°C on the outlet side. Additionally, the layout of the heat exchanger is unknown, and this directly affects the efficiency of heat exchange. Of course, the most direct and quick method is to introduce steam directly into the water, with no heat loss (or very little). The time it takes for heat to be transferred through the water is the heating time, and this transfer process can be accelerated by stirring
As fast as you want, or as slow as you want