基于小型ORC涡旋膨胀机变工况特性研究及实验验证

Based on the study of variable operating conditions and experimental verification of a small-scale ORC with a scroll expander

涡旋膨胀机作为有机朗肯循环(organic Rankine cycle,ORC)核心部件之一,其运行特性直接影响了ORC的性能。首先,建立了涡旋膨胀机的三维瞬态仿真模型,通过数值模拟的方法,系统地分析了不同工况下吸气压力、排气压力、转速和对涡旋膨胀机输出功率和等熵效率的影响;其次,分析了不同工况对涡旋膨胀机瞬态性能的影响,较为全面地分析了其中的机理;最后,通过实验室搭建的ORC低温余热无油发电系统试验台验证了数值模型的准确性,实验结果与数值模拟结果吻合良好,验证了数值模拟方法的可靠性和适用性。研究结果对涡旋膨胀机的设计和优化具有重要的参考价值。

As a fundamental component of the organic Rankine cycle(ORC),the scroll expander’s operating characteristics critically influence the ORC’s overall performance.Initially,we establish a three-dimensional transient simulation model of the scroll expander.This allows us to systematically analyze the effects of various operating conditions on aspects such as suction pressure,exhaust pressure,rotational speed,and the output power and isentropic efficiency of the scroll expander,using numerical simulation.Following this,we study the effect of different operating conditions on the transient performance and mechanical properties of the scroll expander,and achieve a more comprehensive understanding of the mechanisms involved.Ultimately,we verify the accuracy of our numerical model using a laboratory-built test bench of the ORC low-temperature waste heat oil-free power generation system.The close correlation between the experimental results and numerical simulation outcomes authenticates the reliability and applicability of our numerical simulation method.In conclusion,this research’s findings offer significant referential value for the design and optimization of the scroll expander.