Abstract. To carry out research, a complex of gas-dynamic design and profiling of a two-stage centrifugal compressor with an axial-radial impeller has been developed. It is a continuous process of solving the inverse and direct problem of gas-dynamic design, profiling the flow section with subsequent analysis of the rational velocity distribution of an inviscid flow on the impeller blades on axisymmetric streamline surfaces.

Abstract. The paper shows the results of calculation internal head characteristics of the intermediate low-flow centrifugal compressor stages impellers. The type of stages is used at the last stages of multistage centrifugal compressors of the high and ultrahigh pressure. Inviscid quasi-three-dimensional and viscous three-dimensional calculation methods are used. Numerical models of the objects of study represent the flow part of the impeller and the blade-free diffuser with width equal to the height of the blade at the output of the impeller. For a CFD calculation, two interfaces are considered: frozen rotor and stage. It is found that the most qualitative character has a viscous calculation with the Stage interface and inviscid quasi-three-dimensional calculation.

Abstract. The aim of this work is the validation study for the numerical modeling of characteristics of a multistage centrifugal compressor for natural gas. In the research process was the analysis used misyachna interfaces and software systems. The result revealed discrepancies between the simulated and experimental characteristics and outlined the future work plan.

Abstract. Design modernization of the centrifugal compressor stage test bench with three dimensional impeller blades was carried out for the possibility of holding a series of experimental studies of different 3D impeller models. The studies relates to the problem of joint work of the impeller and the stationary channels of the housing when carrying out works on modernization with the aim of improving the parameters of the volumetric capacity or pressure in the presence of design constraints. The object of study is the experimental single end centrifugal compressor stage with the 3D impeller. Compressor stage consists of the 3D impeller, vaneless diffuser (VLD), outlet collector — folded side scroll and downstream pipe. The drive is a DC motor 75 kW. The increase gear (multiplier) was set between the compressor and DC motor, gear ratio is i = 9.8. To obtain the characteristics of the compressor and the flow area the following values were measured: total pressure, static pressure, direction (angles) of the stream in different cross sections. Additional pneumometric probes on the front wall of the VLD of the test bench have been installed. Total pressure probes and foster holes for the measurement of total and static pressure by the new drainage scheme. This allowed carrying out full experimental studies for two elements of centrifugal compressor stage. After the experimental tests the comprehensive information about the performance of model stage were obtained. Was measured geometric parameters and the constructed virtual model of the experimental bench flow part with the help of Creo Parametric 3.0 and ANSYS v. 16.2. Conducted CFD calculations and verification with experimental data. Identifies the steps for further experimental and virtual works.

The purpose of this work is to test the nonlinear harmonic method (NLH), intended for simulation of the unsteady aerodynamic interaction between the rotor and stator of the turbomachine, characterized by high speed of calculations in comparison with the fully unsteady flow calculation approach. Calculations of unsteady flows in turbomachines belong to the class of compute-intensive tasks and to solve real problems in a reasonable time requires the use of supercomputers. The Department of compressor, vacuum and refrigeration engineering for testing the obtained solution of two-dimensional and three-dimensional flows in Turbomachinery using this NLH method, implemented in the software package NUMECA Fine/Turbo. To date, a comparison of the behavior of unsteady flow with the steady solution. Obtained flow patterns and considered conservativeness of flow parameters.