Construction of pressure characteristics of a centrifugal radial fan using ANSYS CFX software package
Authors:   State Biotechnological University, Melnik V. , Zelensky О. ,   State Biotechnological University, Zelensky А. ,   State Biotechnological University
Published: August 2024

Purpose. Improve the design and pressure characteristics of the centrifugal radial fan (CRF), reduce costs and design time by using modern design methods. Methods. Analytical study of the energy characteristics of the CRF using CFD software packages. Three-dimensional modeling of the flow of air in the flow part of the fan. Results. The paper describes the peculiarities of construction of the pressure characteristic of a centrifugal radial fan using the ANSYS CFX program. Numerical simulation of the flow was carried out to improve the initial indicators at the preliminary stage of the design of the CRF. This approach allows reducing costs and design time compared to the experimental approach and provides an opportunity to improve and analyze the performance of the fan and its design without manufacturing it. The use of a calculation complex of programs for the justification and analysis of the design results provides an opportunity to see the picture of the pressure distribution along the flow part, the field of velocity vectors and the movement of the air flow. By means of numerical modeling of the spatial air flow in the flow part of the fan, choosing the SST-turbulence model, the regularity of the change in the pressure characteristic of the fan was the distribution of velocities and pressures in different elements of the air conditioning system, at different values of the mass flow of air, was determined. An analysis of the change in total and static pressure in the flow part of the CRF was performed: in the stator – an inlet nozzle, in the rotor – a closed type impeller, and in the stator – made in the form of a snail. The question of the dependence of the total and static efficiency on the mass flow rate of the fan is also considered. Conclutions 1. Studies of the process of construction of the pressure characteristic of the CRF showed that the proposed approach allows you to reliably estimate the parameters of the fan’s operating modes, determine the main features of the change in determined. As a result of the calculation, efficiency and the distribution of full and static pressure in the elements of the flow part for its further improvement. 2. A distinctive feature of the proposed method of constructing the pressure characteristic is that in the early stages it is possible to predict the hydrodynamic parameters of the flow part of the designed fan without creating its solid-state model. And based on the results of a numerical study of the spatial air flow, it is possible to quantitatively and qualitatively analyze the elements of the flow part of the fan and specify their geometric dimensions for further calculation based on average parameters. 3. The ANSYS 19.0 CFX software complex allows you to immediately display changes in the design of fan assemblies and obtain the results of a numerical study of the spatial air flow in the flow part of the fan. Using the proposed graphic materials, it is possible to visually observe the processes taking place in the flow part of the CRF. The possibility of numerical calculation of the parameters of interest is also shown. 4. The creation of a real CRF to evaluate its performance requires significant funding and is time- consuming, while the use of CFD is fast and cost- effective. The ANSYS 19.0 CFX software package makes it possible to visually present a picture of the behavior of a wide range of process parameters that occur in the flow part of the fan and to show their relationship with the features of the geometry and dimensions of the fan. Keywords: total pressure, static pressure, nozzle, impeller, volute, CFD, mass flow, total efficiency, static efficiency.