Numerical study on the flow characteristic of shell-side film flow of floating LNG spiral wound heat exchanger

A mathematic-physical model was established to investigate the shell-side flow characteristic of film flow in spiral wound heat exchanger (SWHE), which was used for floating liquefied natural gas (FLNG). The numerical study was carried out based on CLSVOF model and dynamic contact angle model, and the numerical accuracy was validated by experimental data. According to the results under static conditions, the shell-side frictional pressure drop gradient increased with decreasing pressure and increasing mass flux and heat flux. Sloshing motion could significantly shorten the process of film flow in the heat exchanger, promote the early occurrence of flow pattern transition and lead to the remarkable change in frictional loss. Therefore, the effects of sloshing parameters and working parameters on shell-side frictional pressure drop gradient were investigated, where sloshing amplitude, sloshing period, pressure and mass flux respectively were 5 similar to 15 degrees , 5 similar to 15 s , 0.2 similar to 0.6 MPa and 60 similar to 100 kg / (m(2)center dot s) . As a result, in order to maintain the stable operation of FLNG SWHE, the heat exchanger should be placed near the gravity center of FLNG, and the shell-side pressure and mass flux should be respectively increased to 0.6 MPa and 80 kg / (m(2)center dot s) , as far as possible. These results will provide some instructions in the design and operation for FLNG SWHE. (c) 2022 Elsevier Ltd. All rights reserved.

Automated summary

In this study, a mathematic-physical model was established to investigate the shell-side flow characteristic of film flow in a spiral wound heat exchanger used for floating liquefied natural gas (FLNG). The results showed that the shell-side frictional pressure drop gradient increased with decreasing pressure and increasing mass flux and heat flux. The sloshing motion significantly shortened the process of film flow, promoted the early occurrence of flow pattern transition, and led to a remarkable change in frictional loss. The effects of sloshing parameters and working parameters on the shell-side frictional pressure drop gradient were investigated.