How should the warning issues in HTRI’s output results be handled?
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I would like to ask the experts here: if the following issues appear in the HTRI output reports, what methods can be used to address them and eliminate these problems? 1. The temperature range for the saturated properties of the hot water (stream) is above the critical temperature of 373.95°C according to the IAPWS-IF97 correlations. The saturated properties for all areas above this temperature will therefore be calculated at the critical temperature. 2. A dry-wall mist flow is expected for the boiling fluid; this condition may lead to high tube wall temperatures. It is necessary to check the maximum allowable tube wall temperature. The first issue indicates that the temperature range exceeds the critical temperature, but what exactly does this critical temperature refer to? The second question is about film boiling occurring in the boiling fluid (as I understand it); could it be that the material chosen for the tubes is not suitable?
The general analysis is as follows for reference only: 1. The specified temperature on the hot side is too high; please check the temperature unit and process conditions； 2. Excessive temperature differences cause intense boiling of the fluid on the cold side, which prevents proper heat transfer in the boundary layer; as a result, the temperature of the heat exchange tube becomes relatively high, approaching that of the hot side. Suggestion: If the process conditions of the hot-side fluid are correct, it is possible that the process setup is inappropriate, resulting in waste of high-grade heat sources ；
Thank you, :handshake I need to take a good look at it.
Thank you, I understand now. Since I often encounter situations where chilled water is used as the cooling medium, and the temperature of the heating medium isn’t particularly high, it’s easy for this warning to appear. I think it’s not necessarily the high temperature on the heating side that’s the issue; rather, it’s due to some kind of \"improper setting\" as mentioned by the person on the second floor, which leads to waste of high-grade heat sources； ”