An Attempt to Evaluate the Cycloidal Rotor Fan Performance

Tomasz Stasko,Krystian Smolka,Miroslaw Majkut,Slawomir Dykas

doi:10.4236/ojfd.2019.94019

Abstract

In this work, the cycloidal rotor fan (CRF) performance was estimated by means of a numerical method based on Unsteady Reynolds Averaged Navier-Stokes equations (URANS). The fan with a cycloidal rotor belongs to the positive displacement machines of the rotary type. The numerical algorithm for simulation of the flow in the cycloidal rotor as well as postprocessing of the CFD results was prepared using Ansys CFX CEL. The methodology for the assessment of the CRF performance was proposed and verified. It was found out that the CRF performance strongly depends on the shape of the profile of the applied rotor blade. The NACA 0012 and CLARK Y profiles were tested for the same CRF structure and flow conditions. Also, the crucial importance for the CRF performance has the range of the blade pitch angle change.

Highlights

The application of the cycloidal rotor idea to the fans is not known so far
The transient analysis was made for four rotational speeds and values of maximal blade pitch angle in order to determine cycloidal rotor fan (CRF) performance characteristic
− By estimation of the torques and forces in Ansys CFX, the implementation of the own expressions is recommended

Summary

Introduction

The application of the cycloidal rotor idea to the fans is not known so far. For the time, being the most widespread application of cycloidal rotors is for ship propulsion and control but the origin of the cycloidal rotor relates to the aeronautic domain [1] [2] [3]. From the point of view of a positive displacement machine of the rotary type, the most effective design is the CRF with four blades It presents a compromise between preserving a low oscillation of the flow stream, the complexity of the design and required rotational speed. In the presented work the elaborated CFD algorithm for modelling the flow in the cycloidal rotor fan was used in order to estimate the performance characteristics of this type of machine. It was investigated the influence of the blade profile shape on the CRF performance, the NACA 0012 and CLARK Y profiles were tested. It was attempted to find the optimal blade pitch angle for the given rotational speed of the rotor

Physical and Numerical Model

Cycloidal Rotor Fan Performance Estimation

Findings

Conclusions