РЕЗУЛЬТАТЫ ИССЛЕДОВАНИЙ КОМПРЕССОРНОЙ И ТУРБИННОЙ ЧАСТЕЙ ТУРБОКОМПРЕССОРОВ С ОБЩИМ РАБОЧИМ КОЛЕСОМ ДЛЯ ПРИМЕНЕНИЯ В МАЛОРАЗМЕРНЫХ ДВИГАТЕЛЯХ

Abstract

It is considered the issues of improving small-sized engines through the application of a new type of turbomachines – turbo-compressors with general impeller (TCG) to develop engines and power plants. For example, it is shown a diagram of the simplest small-sized gas turbine engine using TCG. For the systematization of relatively efficient TCG schemes, a classification has been developed and is given in the article, of possible schemes for a turbocharger with a common impeller. The classification is based on 5 possible directions of movement of the working medium in the blade apparatus – axial (parallel to the axis of rotation of the machine), centrifugal, centripetal, diagonal and tangential. To implement one or another flowing pattern in the impeller, it is necessary to select the appropriate shape of the impeller blades and the location of the nozzle, exhaust, suction and discharge channels relative to each other. Depending on the direction of movement of the gas flows, turbo-compressors with a common impeller may have two flow patterns in interscapular impeller space – direct-flow and counter-flow. If the directions of the gas and airflow coincide concerning the axis of rotation of the impeller, then the flow pattern in the TCG is direct-flow, with opposite flow flows it is countercurrent. For carrying out the enlarged gas-dynamic calculation of TCG, formulas are given that make it possible to calculate the circumferential force arising on the blades of the impeller in the compressor and turbine working channels of the TCG. Also, formulas are given, with correction factors, for calculating the power factor of the compressor part and the load factor of the turbine part. In the process of computational and experimental studies, the characteristic of the compressor part of the TCG experimental model was obtained. The test results of the compressor part of the TCG experimental model showed good agreement between the calculated and experimental values. Studies have shown that a turbocharger with a common impeller can be used as part of small-size gas turbine engines and in a turbo-supercharging system of a small-capacity internal combustion engine with not high supercharging.