Search

One-dimensional (1D) design and optimization of the impeller plays a significant role in performance improvement of the centrifugal compressor. However, most of the concentration has been paid to three-dimensional (3D) optimization of blades, few attention was focused on main control parameters determining aerodynamic performance and their optimal combination. Thus, this study innovatively developed a multidisciplinary design method combined with empirical 1D loss models, statistical analysis, and multi-optimization theory. The preliminary design of 1D parameters was developed based on empirical loss models. Besides, the analysis of variance of signal to noise ratio (SNR) was applied to find the main control parameters according to their contributions. To maximize the total pressure ratio and isentropic efficiency, the multi-objective optimization based on grey relational grade (GRG) was used to find the optimal combination of 1D parameters. The results showed that the impeller outlet width and impeller outlet radius are the most sensitive parameters affecting compressor performance. The optimal combination of 1D parameters is obtained. Compared to the initial design, the optimal impeller can reduce consumed power of 2.99%, enhance the isentropic efficiency of 1.24% at design point, and obtain the maximum increment of isentropic efficiency of 2.16% at 50 g/s operating point at 70,000 rpm. • New multidisciplinary design and multi-objective optimization method was proposed. • Analysis of variance of SNR was used to identify main control parameters affecting performance. • The optimal combination was obtained by multi-objective optimization based on GRC. • Optimal impeller has higher isentropic efficiency at design or off-design points. [ABSTRACT FROM AUTHOR]

Summary: Centrifugal air compressors are promising due to their zero emissions, long driving range, and wide fuel sources. The gas foil thrust bearing (GFTB) is considered as one of the key components in the centrifugal air compressor to guarantee the system is oil‐free and reliable due to there is self‐acting and high speed. However, the gas foil thrust bearings were all of lower capacity in previous research. In this study, the effects of each foil and nominal clearance on the static performance are developed experimentally. The optimal GFTB with higher capacity is obtained. The feasibility study of the proposed GFTB is carried out, which is installed on the ultra‐high‐speed centrifugal air compressor. The result shows that the proposed GFTB can run stably and efficiently in the full speed ring, and the high‐pressure ratio and large flow rate of the air compressor also can be ensured. The results play an important role in guiding the stable operation of centrifugal air compressors applied in hydrogen fuel cell vehicles (HFCVs). [ABSTRACT FROM AUTHOR]

Summary: The gas foil bearings (GFBs) are one of the vital components of the air compressor applied in fuel cell vehicles. The design and operating parameters have an impact on the static and dynamic performances of GFBs, the properties of which need to be tailored to match the specific application demands. The influence of excitation frequency, nominal clearance, loading direction, and elastic structure on the performances is experimentally studied in this article. The results show that the displacement increased while the stiffness decreased with the increase in the nominal clearance. The recommended loading position is provided based on the analysis. The largest stiffness is obtained in the GFBs with the radial trisection foil. Considering the high stiffness and low damping, the best GFB aimed at anti‐vibration is obtained. The results can be used as guidelines for component matching in the design and operation of the polymer electrolyte membrane fuel cell system. [ABSTRACT FROM AUTHOR]