Design and verification for tube-side flow and heat transfer test-rig of coil-wound LNG heat exchangers

Coil-wound heat exchangers are the core equipment for liquefaction of natural gas, however, the experimental research on large-scale coil-wound liquefied natural gas (LNG) heat exchangers is relatively weak and the design theory is also imperfect in China. In order to obtain the characters of flow and heat transfer at the tube side of coil-wound LNG heat exchangers, a new experimental method which can simulate the actual coil-wound LNG heat exchangers operation conditions was presented, and then the corresponding test-rig was designed, developed and debugged. For guaranteeing the accuracy of the experimental data, the test-rig was verified by using liquid propane as experiment medium. The tested heat transfer coefficients of propane under different experimental conditions were compared with those from the classic tube heat transfer correlations in the same experimental conditions. It is concluded that the experimental conditions can meet the actual coil-wound LNG heat exchangers operation conditions, and the test-rig can operate stably. The deviation between the tested values and the predicted values is less than ±10%. So the accuracy of the test-rig is high and the experimental data are credible. The test-rig provides an experimental basis for comprehensive research on flow and heat transfer under the actual conditions for large-scale coil-wound heat exchangers.