韩荣，蒋炎坤*，陈烨欣
华中科技大学能源与动力工程学院，湖北武汉430074
摘要：设计独立的换热器，降低水下工作柴油机中高负荷工况的排气温度。运用SolidWorks建立换热器模型并进行仿真分析，研究圆柱形换热器4种换热管布置方式对换热器温降与压损的影响。分析结果表明：设计的换热器可将排气温度由550.00 ℃降低到161.94 ℃，废气在换热器中的压损为5.95 kPa，降温效果和压损均满足相关工程要求；换热管管径和管心距不变，正三角形和转角三角形布置方式的换热器换热管数量较多，换热面积较大，换热效果较好，其中正三角形布置方式换热器的换热效果更好，但压损更高。本研究可为水下动力装置排气降温系统设计提供参考。
关键词：柴油机；排气降温系统；管壳式换热器；结构设计；流体仿真
Abstract:To reduce the exhaust temperature during high load operation in a underwater diesel engine, a separate heat exchanger is designed. The heat exchanger is modeled using SolidWorks and simulated using CFD technology. The effect of four heat exchanger tube arrangements on the temperature drop and pressure loss of the heat exchanger is investigated. The results show that the designed heat exchanger can reduce the exhaust gas temperature from 55000 ℃ to 16194 ℃, the pressure loss of exhaust gas in the heat exchanger is 595 kPa, the temperature reduction and pressure loss meet the relevant engineering requirements. It is also shown that more tubes could be mounted without changing the heat exchanger tube diameter and tube centre distance for the square triangle and corner triangle arrangement of the heat exchanger,the heat transfer area is larger and the heat transfer effect is better.In contrast to the corner triangle arrangement, the square triangle arrangement has a better heat transfer coefficient, but a higher pressure loss. This study can provide a reference for the design of exhaust cooling systems for underwater power plants.
Keywords:diesel engine;exhaust cooling system; shell and tube heat exchanger; structural design; fluid simulation
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