Computational study of influence by rotating vaneless diffuser on the performance of centrifugal compressor
16 Feb 2021-Vol. 2316, Iss: 1, pp 030025
TL;DR: In this article, the performance of rotating vaneless diffusers with the stationary diffuser is compared using several performance characteristics such as total pressure ratio, static pressure recovery coefficient, coefficient of torque and stagnation pressure loss coefficient.
Abstract: In the present study rotating vaneless diffusers are considered to minimize energy losses associated with diffusion and to improve the operating range of the compressor. Depending on the speed of rotation the diffusers are classified into two types forced and free. Simulations using ANSYS CFX 17.2 are performed with free rotating diffusers, in which diffusers are rotated at fraction of impeller speed. The performance of rotating diffuser with the stationary diffuser is compared using several performance characteristics such as total pressure ratio, static pressure recovery coefficient, coefficient of torque and stagnation pressure loss coefficient are plotted in each case. Simulations are performed at different speed ratio over a range of 0.25-0.95. Among all the cases vaneless diffuser with speed ratio 0.75 has optimum performance in terms of performance characteristics and velocity streamlines are uniform with lower Mach number compared to the stationary vaneless diffuser.
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TL;DR: Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2000 as discussed by the authors, Boston, Massachusetts, USA.
Abstract: Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2000.
90 citations
01 Jul 1997
TL;DR: In this article, the aerodynamic design and manufacturing coordinates for an advanced 4:1 pressure ratio, single stage centrifugal compressor at a 10 lbm/sec flow size were defined.
Abstract: The objective of this program was to define the aerodynamic design and manufacturing coordinates for an advanced 4:1 pressure ratio, single stage centrifugal compressor at a 10 lbm/sec flow size The approach taken was to perform an exact scale of an existing DDA compressor originally designed at a flow size of 3655 lbm/sec
55 citations
TL;DR: In this article, an impeller and diffuser response model is used to predict the nonuniformity of the volute inlet flow due, to the circumferential variation of the pressure at the inlet, and is therefore applicable also at off-design operation of a volute.
Abstract: This paper describes a new model for the analysis of the flow in volutes of centrifugal compressors. It explicitly takes into account the vortical structure of the flow that has been observed during detailed three-dimensional flow measurements. It makes use of an impeller and diffuser response model to predict the nonuniformity of the volute inlet flow due, to the circumferential variation of the pressure at the volute inlet, and is therefore applicable also at off-design operation of the volute. Predicted total pressure loss and static pressure rise coefficients at design and off-design operation have been compared with experimental data for different volute geometries but only one test case is presented here. Good agreement in terms of losses and pressure rise is observed at most operating points and confirms the validity of the impeller and diffuser response model.
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