Temchenko S. Inverse problem for aerodynamic optimal design of turbomachinery annular diffuser ducts

Research object - the aerodynamic processes in the turbomachine flow part. The purpose of dissertation - for the calculation of axisymmetric flow in the annular diffuser channels of the turbomachinery design method for solving direct and inverse problems of aerodynamics, which takes into account the organization of computing processes for solving problems of optimal design of transition and exhaust diffusers. Methods: computational and theoretical methods of research stream flow in turbomachinery annular diffusers based on the fundamentals of gas dynamics and numerical mathematical methods. Theoretical and practical results: developed solution method of direct and inverse aerodynamic problems for annular diffuser channels of turbomachines setting, which became the basis for the optimum design of diffusers; completed the optimum design of the annular diffuser channel having a degree of expansion and geometrical parameters typical for the exhaust diffuser of compressors and gas turbine, thereby provided low coefficient of total losses and unseparated flow pattern and 20% decrease of the axial dimension compared to prior to separation diffuser with straight outline. The novelty: for the first time was proposed numerical method which allows to solve both direct and inverse aerodynamic problem for axisymmetric flow in the annular channels with a single methodological position with the same accuracy of the results; for the first time was developed optimal design method of unseparated annular diffuser channels with given degree of expansion, radial and axial dimensions based on inverse aerodynamic problem. Degree of the implementation: PJSC "Turboatom", Ukraine (Kharkiv), the department of turbomachinery NTU "KHPI" (Kharkiv). Use: turbine construction.