Design and features of the ECC-55 experimental rig for gas-dynamic tests of model centrifugal compressor stages

2021 ◽  
Author(s):  
A. I. Borovkov ◽  
Yu. B. Galerkin ◽  
A. A. Drozdov ◽  
A. F. Rekstin ◽  
V. B. Semenovskiy ◽  
...  
2018 ◽  
Vol 61 (1) ◽  
pp. 134-137
Author(s):  
S. S. Evgen’ev ◽  
V. A. Futin

2018 ◽  
Vol 54 (4) ◽  
pp. 4-10
Author(s):  
M. Kalinkevych ◽  
V. Ihnatenko

Gas-dynamic characteristics of the compressor make it possible to evaluate its energy and economic properties, to predict the values of capacity, the generated gas pressure and the power consumption during the compressor operation. For more in-depth consideration of the compressor, it is desirable to have the characteristics of its individual stages. The element-by-element analysis of the characteristics of each stage makes it possible to improve the coordination of the operation of the individual elements with each other and thereby improve the gas-dynamic characteristics of the compressor. The loss factor and the static pressure recovery factor can be used as the values characterizing the properties of the individual elements of the stage. Coefficients are suitable for evaluating the energy properties of any element of the stage. To assess the effect of the element in question on the economy of the stage, it is necessary to establish what proportion of the work required for compression is the "loss" of energy in a given element, i.e. find the reduction in efficiency stage due to dissipation of energy into heat in this element. Calculation of performance of the centrifugal compressor is performed from the inlet to the outlet using the equations of state, of process, of continuity and conservation of energy. The initial data are geometric parameters of the compressor, the composition and the initial parameters of compressed gas, the rotational speed of the rotor. The basis of the elementwise calculation of gas-dynamic characteristics is the gas-dynamic characteristics of the stage elements. The calculation can be performed using the characteristics of the stage elements taken from the own bank of experimental data or using the generalized characteristics of the stage elements. To obtain generalized characteristics of the impeller, blade and no-blade diffusers, reverse guide vanes, experimental data were used, published in the works of Galerkin, Den, Rees, Seleznev and others, as well as experimental data obtained by the author. The generalized characteristics are obtained in the form of analytical dependences of the loss coefficients on the angles of attack or flow angles by approximation of experimental data. These dependences were used to analyze the gas-dynamic characteristics of a centrifugal compressor, which made it possible to develop recommendations for their improvement.


2019 ◽  
Vol 140 ◽  
pp. 05003 ◽  
Author(s):  
Aleksandr Nikiforov ◽  
Alexei Kuchumov ◽  
Sergei Terentev ◽  
Evgeniy Petukhov ◽  
Kirill Kabalyk

The paper presents the results of mathematical simulation of the characteristics of a vane diffuser of a centrifugal compressor intermediate stage, such as the loss coefficient and the deviation angle versus the outlet vane angle of the diffuser. The simulation of these characteristics was made on the basis of processing the results of studies performed by the Research Laboratory “Gas Dynamics of Turbomachines” of Peter the Great St.Petersburg Polytechnic University at the model characteristics of vane diffusers. Given the almost complete absence of recommendations in the literature, the paper describes the technology for constructing neural network models, which includes preparing a sample of input data and determining the optimal structure of the neural network. Based on the obtained mathematical models, a computational experiment was carried out in order to determine the influence of the main geometric and gas-dynamic parameters on the efficiency of vane diffusers. The results of the computational experiment on neural models of the efficiency of a vane diffuser are analyzed according to the existing ideas about the physics of the processes of energy conversion in a vane diffuser.


2018 ◽  
Author(s):  
S. M. Beloborodov ◽  
V. Yu. Petrov ◽  
V. Ya. Modorskii ◽  
M. L. Tselmer
Keyword(s):  

Author(s):  
О.А. Solovyeva ◽  
А.А. Drozdov ◽  
E.Yu. Popova ◽  
K.V. Soldatova

The centrifugal compressor design involves the use of approximate engineering techniques based on mathematical modeling. One of such techniques is the universal modeling method, which proves to be practically applicable. Having generalized a series of CFD calculations, we used a mathematical model in the latest version of the compressor model to calculate flow parameters in vaneless diffusers. The diffuser model was identified based on the results of experimental studies of average-flow model stages carried out at SPbPU. The model is also used to calculate Clark low-flow centrifugal compressor stages with narrow diffusers with a relative width in the range of 0.5--2.0 %. For these stages, the developed mathematical model showed insufficient efficiency, since the dimensions of the diffusers go beyond the limits of its applicability. To solve this problem, we calculated a series of vaneless diffusers with a relative width in the range of 0.6--1.2 % in the ANSYS CFX software package. Relying on the results of CFD calculations, we plotted the gas dynamic characteristics of the loss coefficients and changes in the flow angle depending on the flow angle at the inlet to the vaneless diffuser. To process the calculated data, the method of regression analysis was applied, with the help of which a system of algebraic equations was developed that connects geometric, gas-dynamic parameters and similarity criteria. The obtained equations are included in a new mathematical model of the universal modeling method for calculating the flow parameters of vaneless diffusers. Comparison of the calculated gas-dynamic characteristics according to the new model with experimental data showed the average error of modeling the calculated (maximum) efficiency equal to 1.08 %


Author(s):  
P. M. Came

A computer-based centrifugal compressor design procedure developed at the National Gas Turbine Establishment is described. The impeller design package includes a geometry modelling procedure, aerodynamic analysis, stress analysis, and the direct generation of data for manufacture by numerical control. The method of diffuser design incorporates analyses of the flow in the vaneless space and ‘semi-vaneless’ space adapted from a new performance prediction technique; published diffuser pressure recovery data are used in the selection of the diffuser channel geometry. The application of these methods to the design of a 6.5 pressure ratio centrifugal compressor stage is described. The experimental rig testing of this compressor has been used to evaluate the advantages offered by the new design procedure. By comparing the measured performance with that of an earlier compressor designed with less advanced techniques for the same aerodynamic duty, the advantages of the new design procedure are established.


2017 ◽  
Vol 803 ◽  
pp. 012097 ◽  
Author(s):  
V N Matveev ◽  
L S Shabliy ◽  
A V Krivcov
Keyword(s):  

2020 ◽  
Vol 178 ◽  
pp. 01014
Author(s):  
Olga Solovyeva ◽  
Aleksandr Drozdov

The approximate engineering techniques based on mathematical modelling are used in centrifugal compressor design. One of such methods is the well-proven Universal Modelling Method, developed in the scientific and research laboratory “Gas dynamics of turbo machines”, SPbPU. In the modern version of the compressor model, vaneless diffusers mathematical model was applied based on a generalization of the CFD calculations. The mathematical model can be used for vaneless diffusers with a relative width in the range of 1.4 – 10.0%, with a radial length up to 2.0, in the range of inlet flow angles 10 to 90 degrees, the inlet velocity coefficient in the range of 0.39 – 0.82, Reynolds number varying from 87 500 to 1 030 000. The model was also used for calculating low-flow-rate model stages with narrow diffusers with diffusers’ relative width in the range of 0.5 – 2.0%. The mathematical model showed lesser accuracy. To widen the model applicability, new series of CFD-calculations were executed. A series of vaneless diffusers was designed with relative width in the range of 0.6 – 1.2%, The gas-dynamic characteristics of loss coefficients and outlet flow angle versus inlet flow angle of diffuser were calculated. Regression analysis was used to process the calculated data. System of algebraic equations linking geometric, gas-dynamic parameters and similarity criteria was developed. The obtained equations are included in a new mathematical model of the Universal Modelling Method.


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