Inverse Design Method for Centrifugal Compressors in Carnot batteries

This paper presents a new inverse design method for centrifugal compressors, meant for researchers in the field of thermodynamic cycle design. It extends the state of the art in centrifugal compressor design methods by offering a fully automated way of designing centrifugal compressors for any given compression task. For the optimization of cycle designs and the generation of precise estimations of cycle performance, knowing the efficiency of any compression involved in the cycle is of great importance. The turbomachinery design process requires much specific knowledge and is time-consuming, taking away from the work of designing the cycle layout. In fields such as Carnot batteries, where heat pumps or organic Rankine cycles are commonly encountered, established design rules are unavailable and no standard solutions exist. This necessitates a method for the design of compressors, which takes little time and effort, requires no specific knowledge by the user and can be integrated into optimization routines. Design methods described in literature commonly start after the most basic characteristics of the compressor such as the number of stages and rotational speed have already been chosen by the designer. This requires specific knowledge and design experience. This paper extends these methods by integrating these decisions into the method. The user only has to provide the desired compression task. Afterward, the aerodynamic as well as mechanical inverse design methods are employed to decide upon a principal compressor design. The design is further refined through mean line analysis. The geometry of the flow path is created in detail and the performance of the compressor is determined. Through the use of real gas equations of state for the thermodynamic calculations a wide range of working fluids and operating conditions can be analyzed. The designs created by this method are analyzed for varying compression tasks stemming from the area of thermal energy storage. To validate the suitability of the designs created, they are compared to results obtained through computational fluid dynamics.