Service and cleaning of heat exchangers

It’s as if there are mountains between them; the original poster’s translations are inappropriate. Feel free to come and discuss: Fouling resistance – heat resistance due to fouling; Heat exchanged – amount of heat transferred; Transfer rate – heat transfer coefficient; Service – medium used for heat transfer; Clean – cleaning fluid (referring to the heat transfer rate under different conditions); MTD – mean temperature difference. Note: From an English perspective, Transfer rate should refer to the heat transfer rate, but given the unit of W/m²°C, it is usually the heat transfer coefficient. The unit for heat transfer rate is W/m². There are many definitions available online, so they won’t be listed here

The original poster has the opportunity to download the ASME codes from this forum. In the official translation: Service uses \"clean\" for cleaning, and \"Corrected\" for the correction values

By combining the knowledge of chemical engineering principles learned with some information found through research. I think: these are some parameters of the heat exchanger. And it is very likely to be the simulation result of a heat exchanger simulation software. Agreeing with solar3124: Fouling resistance, Heat exchange resistance; Heat exchanged – the amount of heat transferred. First, regarding MTD (Corrected): here, “corrected” refers to the corrected average temperature difference. In heat exchangers, this is referred to as the “logarithmic temperature difference” (the temperature difference that is corrected by using logarithms). For plate heat exchangers, the logarithmic temperature difference is calculated as follows: Logarithmic temperature difference △t = ((Ti – To) – (to – Ti)) / ln((Ti – To) / (to – Ti)). Ti: Temperature of the hot fluid at the inlet, in K; To: Temperature of the hot fluid at the outlet, in K; ti: Temperature of the cold fluid at the inlet, in K; to: Temperature of the cold fluid at the outlet, in K; ln: Natural logarithm. Secondly: Transfer rate: Service/Clean. The transfer rate represents the overall heat transfer coefficient of the heat exchanger. There are three types of Service/Dirty Clean. Dirty represents the overall heat transfer coefficient with account taken of the fouling thermal resistance; clean represents the overall heat transfer coefficient without considering such resistance; whereas service is the overall heat transfer coefficient calculated based on the actual heat transfer area of the heat exchanger. Personally, I think it’s actually possible to leave it in English; professionals know what it refers to. I couldn’t find a suitable translation, and I think \"work,\" \"dirt,\" or \"clean\" might work. For better understanding, please see the following: It is as follows: Service 315 – Dirty: 508.2; Clean: 752.1. These three values represent the overall thermal conductivity of the heat exchanger, with the unit being [W/(m2*K)]. The area used for calculating the heat exchanger is based on the value for Service 315, denoted here as U. In the table, there are also these three values: Surf/unit(eff.) represents the effective heat exchange area A [m2], Heat exchanged represents the amount of heat transferred Q [W], and MTD corrected represents the logarithmic temperature difference. The relationship between them is Q = A * U * MTD, with all values derived from Service 315. Service/Clean = obtained area margin. The relationship between Clean and Dirty is 1/Clean + Fouling resist(shell) + Fouling resist(tube) = 1/Dirty. Refer to the post on HCBBS: http://bbs.hcbbs.com/viewthread.php?tid=200182. This post was last edited by niuky on 2008-12-31 at 18:40.]

"These are some parameters of the heat exchanger. And it is very likely to be the simulation result of a heat exchanger simulation software. " It is the output result of HTRI or HTFS

Clean: Cleaning fluid (referring to the heat transfer rate under different materials). Service: Medium

Generally speaking, the opposite of clean is dirty; one refers to the cleaning pressure drop and the other to the clogging pressure drop. However, this is not what is meant in this article – I was just giving an example above. In this text, the transfer rate refers to the heat transfer amount; therefore, service and clean refer to the heat transfer amounts in the operating state and the cleaning state, respectively. Additionally, Shell side refers to the shell side of the heat exchanger, while Tube Side refers to the tube side. In and out represent import and export respectively.

:o :o Everyone here is really professional, especially those on the fourth floor. Thank you :handshake

Correct! The transfer rate is the overall heat transfer coefficient of the heat exchanger. There are three types of Service/Dirty Clean. Dirty represents the overall heat transfer coefficient with account taken of the fouling thermal resistance; clean represents the overall heat transfer coefficient without considering such resistance; whereas service is the overall heat transfer coefficient calculated based on the actual heat transfer area of the heat exchanger.

We can discuss it in more detail upstairs

11# whq520 agrees with the view on the fourth floor