Abstract: ORC system was used to recover the waste heat of a certain type of ship diesel engines（maximum continuous rating 996 kW）. The performances of five different structure ORC systems were compared and analyzed on their net output powers. The results show that the maximum net output power of the basic ORC system that recovers the exhaust gas waste heat of the ship diesel engines is as 49.83 kW； by only adding a regenerator to further recover the waste heat of the expander outlet working fluid， the maximum net output power reaches 54.84 kW； while by adding a preheater to recover the waste heat of the ship diesel engine jacket cooling water， the number is up to 58.88 kW， which is 18.1% higher than that of the basic ORC systems. Using the independent dual-cycle ORC system to recover the waste heat of ship diesel engine exhaust gas and jacket cooling water simultaneously only make the maximum net output power 2.84% higher than that of the ORC system with preheater， which is as 60.6 kW. Therefore， considering of ship space constraints， operation and maintenance reliability， the ORC system with preheater should be given priority to recover the waste heat of the ship diesel engines.

Key words: ship diesel engine, waste heat recovery, organic Rankine cycle（ORC）, performances analysis

摘要： 利用有机朗肯循环（ORC）系统对某型号船舶柴油机（最大持续功率为996 kW）的余热进行回收，以系统净输出功为指标，对比分析5种不同结构形式的ORC系统的热力学性能，结果表明：回收柴油机排烟余热的基础ORC系统最大净输出功达49.83 kW；增设回热器进一步回收膨胀机出口工质废热后，系统最大净输出功达54.84 kW；增设预热器回收柴油机缸套冷却水余热后，系统最大净输出功达58.88 kW，比基础ORC系统提高18.1%；通过独立双循环ORC系统同时回收柴油机排烟余热和缸套冷却水余热时，系统最大净输出功为60.6 kW，仅比带预热器ORC系统高2.84%。因此，考虑到船舶空间受限以及运维可靠性等因素，应优先考虑采用带预热器ORC系统来回收该船舶柴油机的余热。

关键词: 船舶柴油机, 余热回收, 有机朗肯循环, 性能分析