Coordination Funds

协调基金

• 批准号: 531152024
• 负责人: Professor Dr.-Ing. Markus Richter
• 金额: --
• 依托单位: Professur Technische Thermodynamik
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/531152024?language=en
• 关键词: Coordination; Funds

The main objective of the Research Unit FOR 5595 is to develop a valid calculation model for multiphase surge and gap flows for oil-refrigerant mixtures in rotary positive displacement compressors (RPDC) based on novel microscopic and macroscopic approaches for experiments and simulations. A crucial prerequisite for this model development is the knowledge of the occurring flow patterns (e.g., bubbly, surge, mist flow), which depend significantly on the thermophysical properties of the fluid mixtures and operating boundary conditions. The small gap heights (< 0.3 mm) in connection with moving gap boundaries make a combined experimental and numerical flow analysis necessary. On the generic experimental model of a rotating body in a cylindrical glass housing, a new laser-optical framework for the spatially and temporally resolved measurement of the two-phase surge and gap flow is tested and compared with high-resolution flow simulations. Based on this, a calculation model for multiphase flow in narrow gaps with moving boundaries is developed. The oil-refrigerant mixtures used exhibit a strongly asymmetric mixing behavior. For such mixtures, the relevant thermophysical properties are measured systematically and accurately for the first time and are transferred into precise equations of state and transport property models. The structure of the models is designed to be transferable to other strongly asymmetric mixtures. Moreover, in order to apply the models in flow simulation, attention is paid to acceptable computational speed. The new models for the thermophysical properties of the fluid mixtures together with the new calculation approaches for the multiphase surge and gap flows will enable an improved design of efficient RPDC for oil-refrigerant mixtures in the future and, thus, contribute to the reduction of the consumption of resources.

研究单元FOR 5595的主要目标是基于新的微观和宏观实验和模拟方法，为旋转式容积式压缩机（RPDC）中油-制冷剂混合物的多相喘振和间隙流开发一个有效的计算模型。该模型开发的一个关键先决条件是了解发生的流型（例如，气泡流、喘振流、雾流），这在很大程度上取决于流体混合物的热物理性质和操作边界条件。与移动间隙边界相关的小间隙高度（< 0.3 mm）使得结合实验和数值流动分析成为必要。在圆柱形玻璃外壳中的旋转体的通用实验模型上，对用于两相喘振和间隙流的空间和时间分辨测量的新的激光光学框架进行了测试，并与高分辨率流模拟进行了比较。在此基础上，建立了动边界窄缝多相流计算模型。所使用的油-制冷剂混合物表现出强烈的不对称混合行为。对于这样的混合物，相关的热物理性质的测量系统和准确的第一次，并转移到精确的状态方程和传输属性模型。模型的结构被设计成可转移到其他强不对称混合物。此外，为了将模型应用于流动模拟，注意可接受的计算速度。流体混合物的热物理性质的新模型以及多相喘振和间隙流的新计算方法将使得未来能够改进用于油-制冷剂混合物的高效RPDC的设计，从而有助于减少资源消耗。