Modeling and investigation of the efficiency of a centrifugal fan with backward-curved

Abstract

Particular attention is paid to improving the efficiency of ventilation systems in mechanical engineering, especially in the design of power equipment and aircraft. One of the promising directions in this area is optimizing the aerodynamic characteristics of centrifugal fans equipped with backward-curved blades, which provide high efficiency over a wide range of operating conditions. The fan design, specifically the shape and type of impeller, significantly affects the total pressure losses in air supply channels and the overall aerodynamic performance of the system. This study presents the results of a numerical investigation of the characteristics of a centrifugal fan with backward-curved blades, comparing two design configurations: one with an open impeller and the other with a closed impeller. Combining CFD modeling with geometric optimization enhances the accuracy of calculations and contributes to the overall effectiveness of the design solutions. The influence of the impeller type on airflow rate, total pressure, and efficiency is given particular attention. Numerical simulations were conducted to evaluate the flow characteristics inside the impeller and at the fan outlet using Ansys CFX. The BladeGen module was used to create the impeller geometry, which allowed for the precise shaping of the blades and enabled further analysis in the CFD environment. Additional aerodynamic evaluations of the fan were conducted using various simulation tools within Ansys, providing a more comprehensive understanding of performance under different design conditions. The numerical modeling results enabled a detailed analysis of how the aerodynamic performance of the fan depends on the type of impeller used. The efficiency of two types of impellers under identical boundary conditions is a distinctive feature of this study. The closed impeller provides superior performance and greater stability of operational parameters, particularly under high-load conditions. This improvement is attributed to more efficient airflow control, reduced vortex formation, and decreased losses caused by air leakage through the system’s gaps. The numerical approach developed in this research allows for the formulation of general recommendations regarding the selection of the impeller type depending on the ventilation system’s specific operating conditions. The combination of CFD simulation and geometry optimization not only ensures more accurate predictions of fan behavior but also supports the development of more energy-efficient and reliable ventilation equipment. Thus, the findings of this study have practical implications for the engineering design process, particularly in sectors where ventilation performance is critical to system efficiency and operational reliability.