Effect of compound sloshing conditions on pressure drop and heat transfer characteristics for FLNG spiral wound heat exchanger

Abstract

Floating liquefied natural gas (FLNG) is a promising floating production equipment which integrates the gas extraction, liquefaction, storage, loading and unloading of offshore liquefied natural gas. The spiral wound heat exchanger (SWHE) is one of the most important installations of FLNG and the effect of compound sloshing on the performance of the spiral wound heat exchanger attracts a lot of attention. In this work, an experimental device of dual mixed refrigerant (DMR) and a multi-phase four-stream calculation code for SWHE are constructed to study the performance of FLNG SWHE. Quantitative analysis of temperature, pressure drop and enthalpy affected by sloshing periods, displacements and types are completed. Compared with temperatures, pressure drop characteristics of SWHE are much more significantly influenced under sloshing conditions, especially for compound heaving and pitching conditions. The maximum fluctuation range of gas-phase mixed refrigerant pressure drop is from −11.08% to 24.96% for steady state. The temperature of gas-phase mixed refrigerant increases by 6.45 °C and the heat exchange decreases by 37.90 W under compound heaving and pitching conditions.