The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform

Daniel Rusch - One of the best experts on this subject based on the ideXlab platform.

  • the matching of a vaned diffuser with a radial compressor Impeller and its effect on the stage performance
    ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, 2014
    Co-Authors: Michael Casey, Daniel Rusch
    Abstract:

    The matching of a vaned diffuser with a Centrifugal Impeller is examined with a one-dimensional (1D) analysis combined with extensive experimental data. A matching equation is derived to define the required throat area of the diffuser relative to the throat area of the Impeller at different design speeds and validated by comparison with a wide range of compressor designs. The matching equation is then used to give design guidelines for the throat area of vaned diffusers operating with Impellers at different tip-speed Mach numbers.An analysis of test data for a range of high pressure ratio turbocharger compressor stages is presented in which different matching between the diffuser and the Impeller has been experimentally examined. The test data includes different Impellers with different diffuser throat areas over a wide range of speeds. It is shown that the changes in performance with speed and diffuser throat area can be explained on the basis of the tip-speed Mach number which causes both the diffuser and Impeller to choke at the same mass flow. Based on this understanding, a radial compressor map prediction method is extended to include this parameter, so that more accurate maps for matched and mismatched vaned diffusers can be predicted.Copyright © 2014 by ASME

  • The Matching of a Vaned Diffuser With a Radial Compressor Impeller and Its Effect on the Stage Performance
    Journal of Turbomachinery, 2014
    Co-Authors: Michael Casey, Daniel Rusch
    Abstract:

    The matching of a vaned diffuser with a Centrifugal Impeller is examined with a one-dimensional (1D) analysis combined with extensive experimental data. A matching equation is derived to define the required throat area of the diffuser relative to the throat area of the Impeller at different design speeds and validated by comparison with a wide range of compressor designs. The matching equation is then used to give design guidelines for the throat area of vaned diffusers operating with Impellers at different tip-speed Mach numbers. An analysis of test data for a range of high pressure ratio turbocharger compressor stages is presented in which different matching between the diffuser and the Impeller has been experimentally examined. The test data includes different Impellers with different diffuser throat areas over a wide range of speeds. It is shown that the changes in performance with speed and diffuser throat area can be explained on the basis of the tip-speed Mach number which causes both the diffuser and Impeller to choke at the same mass flow. Based on this understanding, a radial compressor map prediction method is extended to include this parameter, so that more accurate maps for matched and mismatched vaned diffusers can be predicted.

S W Armfield - One of the best experts on this subject based on the ideXlab platform.

  • numerical investigation of a small gas turbine compressor
    16th Australasian Fluid Mechanics Conference (AFMC), 2007
    Co-Authors: S W Armfield
    Abstract:

    This paper presents the initial development and study of a Centrifugal compressor undertaken at the Micro Propulsion Group (MPG), University of Sydney. The compressor is used in a small gas turbine engine (108mm diameter). Gerendas et al [1] refer to gas turbines of this size as small aero-engines. The gas turbine chosen for the initial study is the KJ66, which is one of the most robust and primitive small gas turbine designs available. This project is aimed at improving the performance and efficiency of a KJ66 small gas turbine, which currently utilises a 66mm diameter Centrifugal Impeller and radial wedge type diffuser. The proposed replacement Impeller is 71mm diameter, coupled to a mixed flow vaned diffuser to produce a higher pressure ratio at design conditions. The changes were made in such a way that the original engine’s diameter of 108mm was maintained. The geometry of the diffuser vanes was redesigned to ensure effective diffusion, while directing the flow from the radial to axial direction in a smooth turn. In addition to increasing the Impeller diameter, having smooth turns in the stage components is expected to increase compression efficiency, at least in a certain operational range. The work presented here uses Computational Fluid Dynamics (CFD) simulations. The performance and efficiency charts of the original compressor stage, with a KKK2038 compressor wheel coupled to a wedge-type diffuser, were mapped. The performance chart of the new design was also mapped and comparisons are made. The performance of the new stage design is notably better than the original design, within a certain operational range. The power requirement to drive the compressor was also checked to ensure its compatibility with the turbine drive.

Y. Shi - One of the best experts on this subject based on the ideXlab platform.

  • Multidisciplinary analysis transient flow effects on the Impeller in a semi-open Centrifugal Impeller stage
    2017 IEEE 21st International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2017
    Co-Authors: Rong Xie, M. Hao, L Guan, Y. Shi
    Abstract:

    Centrifugal compressors present very complex unsteady characteristics under running. The influence of unsteady aerodynamic load on blades surface may be related to the blade fracture. This issue involves aerodynamics, engineering thermodynamics, structural mechanics, computational fluid dynamics, mathematics, etc. A multidisciplinary analysis method based on CFD software has been applied to predict the flow field in a semi-open Impeller stage of a Centrifugal compressor, to analyze 3D flow characteristics in the transient flow field and aerodynamic load on the blade surfaces. Mechanism with a high amplitude frequency was focused on. Combined with entropy distribution diagrams, the wake vortex shedding frequency and the interference frequency generated by low-energy groups were captured. Results indicate that the wake vortex shedding and the low-energy groups are the main factors causing high aerodynamic load on the Impeller blade. The large pressure pulsation generated by wake vortex shedding and low-energy group may greatly threaten the blade safety. This study provides beneficial references for the analysis of blade fracture causes in a semi-open Impeller stage of a Centrifugal compressor.

Michael Casey - One of the best experts on this subject based on the ideXlab platform.

  • the matching of a vaned diffuser with a radial compressor Impeller and its effect on the stage performance
    ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, 2014
    Co-Authors: Michael Casey, Daniel Rusch
    Abstract:

    The matching of a vaned diffuser with a Centrifugal Impeller is examined with a one-dimensional (1D) analysis combined with extensive experimental data. A matching equation is derived to define the required throat area of the diffuser relative to the throat area of the Impeller at different design speeds and validated by comparison with a wide range of compressor designs. The matching equation is then used to give design guidelines for the throat area of vaned diffusers operating with Impellers at different tip-speed Mach numbers.An analysis of test data for a range of high pressure ratio turbocharger compressor stages is presented in which different matching between the diffuser and the Impeller has been experimentally examined. The test data includes different Impellers with different diffuser throat areas over a wide range of speeds. It is shown that the changes in performance with speed and diffuser throat area can be explained on the basis of the tip-speed Mach number which causes both the diffuser and Impeller to choke at the same mass flow. Based on this understanding, a radial compressor map prediction method is extended to include this parameter, so that more accurate maps for matched and mismatched vaned diffusers can be predicted.Copyright © 2014 by ASME

  • The Matching of a Vaned Diffuser With a Radial Compressor Impeller and Its Effect on the Stage Performance
    Journal of Turbomachinery, 2014
    Co-Authors: Michael Casey, Daniel Rusch
    Abstract:

    The matching of a vaned diffuser with a Centrifugal Impeller is examined with a one-dimensional (1D) analysis combined with extensive experimental data. A matching equation is derived to define the required throat area of the diffuser relative to the throat area of the Impeller at different design speeds and validated by comparison with a wide range of compressor designs. The matching equation is then used to give design guidelines for the throat area of vaned diffusers operating with Impellers at different tip-speed Mach numbers. An analysis of test data for a range of high pressure ratio turbocharger compressor stages is presented in which different matching between the diffuser and the Impeller has been experimentally examined. The test data includes different Impellers with different diffuser throat areas over a wide range of speeds. It is shown that the changes in performance with speed and diffuser throat area can be explained on the basis of the tip-speed Mach number which causes both the diffuser and Impeller to choke at the same mass flow. Based on this understanding, a radial compressor map prediction method is extended to include this parameter, so that more accurate maps for matched and mismatched vaned diffusers can be predicted.

Rong Xie - One of the best experts on this subject based on the ideXlab platform.

  • Multidisciplinary analysis transient flow effects on the Impeller in a semi-open Centrifugal Impeller stage
    2017 IEEE 21st International Conference on Computer Supported Cooperative Work in Design (CSCWD), 2017
    Co-Authors: Rong Xie, M. Hao, L Guan, Y. Shi
    Abstract:

    Centrifugal compressors present very complex unsteady characteristics under running. The influence of unsteady aerodynamic load on blades surface may be related to the blade fracture. This issue involves aerodynamics, engineering thermodynamics, structural mechanics, computational fluid dynamics, mathematics, etc. A multidisciplinary analysis method based on CFD software has been applied to predict the flow field in a semi-open Impeller stage of a Centrifugal compressor, to analyze 3D flow characteristics in the transient flow field and aerodynamic load on the blade surfaces. Mechanism with a high amplitude frequency was focused on. Combined with entropy distribution diagrams, the wake vortex shedding frequency and the interference frequency generated by low-energy groups were captured. Results indicate that the wake vortex shedding and the low-energy groups are the main factors causing high aerodynamic load on the Impeller blade. The large pressure pulsation generated by wake vortex shedding and low-energy group may greatly threaten the blade safety. This study provides beneficial references for the analysis of blade fracture causes in a semi-open Impeller stage of a Centrifugal compressor.