一维/三维耦合复杂时变压缩系统流动失稳机理研究

The compression systems in internal combustion engines and natural gas pipelines are both time-varying, where the pressure/mass flow fluctuation exists on their inlet and outlet boundaries. Traditional numerical methods are incapable of representing the dynamic response characteristics of compression system to the pressure/mass flow fluctuation and considering of the coupling interaction between the components of the compression system, which severely restricts the understanding of flow instability mechanism on time-varying compression system.. This project innovatively proposes the 1D-3D coupling numerical method, whose cores are as follows: the pipes, plenums and valves are modeled in one dimension to represent the propagation characteristics of pressure/mass flow fluctuation; the compressor is modeled in three dimensions to capture the complex three-dimension unsteady flow characteristics; based on the wave propagation mechanism, establishing the data exchange model between one-dimension model and three-dimension model to consider the coupling interaction between the components of compression system. Then the established one-dimension-three-dimension coupling numerical method for time-varying compression system and the compressor experiments with fluctuation generator are employed, to explore the dynamic response characteristics of compression system under time-varying boundary conditions, to reveal the flow instability mechanism of compression system under time-varying boundary conditions and finally to provide the theory support for the development of time-varying compression system high pressure boost technology.

内燃机涡轮增压和天然气长距离管路输运增压均为时变边界压缩系统，其进口和出口边界存在压力/流量波动。传统数值仿真方法无法合理表征时变边界下压缩系统对压力/流量波动的动态响应特性，也无法正确考虑压缩系统各部件之间的相互耦合作用，严重制约了人们对时变压缩系统流动失稳机理的理解。. 本项目创新性的提出一维/三维耦合数值仿真方法，其核心内涵是：对管路、容腔、阀门等系统部件进行一维建模，表征压力/流量波动在其内部的传播特性；对压气机部件进行三维建模，捕捉其内部复杂的三维非定常流动特征；基于波的物理传播机理，建立一维与三维模型之间的数据交互模型，以考虑压缩系统内各部件之间的相互耦合作用。本项目利用所建立的一维/三维耦合时变压缩系统数值仿真方法，结合带脉冲发生器的试验研究方法，重点研究时变边界下变压缩系统的动态响应特性和流动失稳机理，为时变压缩系统高增压技术的发展提供理论支撑。

内燃机涡轮增压和天然气长距离管路输运增压均为时变边界压缩系统，其进口和出口边界存在压力/流量波动。传统数值仿真方法无法合理表征时变边界下压缩系统对压力/流量波动的动态响应特性，也无法正确考虑压缩系统各部件之间的相互耦合作用，严重制约了人们对时变压缩系统流动失稳机理的理解。.本项目创新性的提出一维/三维耦合数值仿真方法，其核心内涵是：对管路、容腔、阀门等系统部件进行一维建模，表征压力/流量波动在其内部的传播特性；对压气机部件进行三维建模，捕捉其内部复杂的三维非定常流动特征；基于波的物理传播机理，建立一维与三维模型之间的数据交互模型，以考虑压缩系统内各部件之间的相互耦合作用。本项目利用所建立的一维/三维耦合时变压缩系统数值仿真方法，结合试验研究，重点研究时变边界下压缩系统的动态响应特性和流动失稳机理，为时变压缩系统高增压技术的发展提供理论支撑。.本项目完成了所有研究内容，达到了预期研究目标，主要取得了以下3项研究成果：1）基于对压缩系统失稳特性的研究，建立了压缩系统一维/三维耦合模型和数值仿真方法，并完成了试验验证；2）基于所建立的方法获取了系统一维特征对压气机动态响应特性及流动失稳影响机理；3）基于所建立的方法获取了压气机三维特征对压气机动态响应特性及流动失稳影响机理。.本项目共发表学术论文25篇，其中SCI收录22篇；申请软件著作权1项；培养学生9人，其中博士生6人，硕士生3人。