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The antennas of modern radar devices need effective cooling, which is carried out by forced circulation of the coolant. A new pneumohydraulic diagram of a refrigerating unit, which allows achieving effective heat removal from an antenna of a radar station with minimal overall dimensions and weight, is considered in this paper. The paper presents the results of experimental research related to an operation of the refrigerating unit at ambient temperatures equal to +50 °C and -50 °C within the temperature range from −50 °C to 10 °C.

164Currently, independent power engineering is being developed by priority rates. It is characteristic of the comparatively low summary power of installations and a reduced ability to reserve power. Many independent power systems are based on gas turbine units (GTUs), and derated conversion aircraft derivative engines prevail among them. The water injection proposed broadens the control limits of GTUs, makes it possible to increase their avaiable power, and perform at its rated setting.Most scientific investigations in this direction are computational [1,2], and the number of experimental investigations and industrial implementations is con siderably smaller [3][4][5]. Both the calculations and the experiment evidence an increase in unit power with injecting water into the compressor inlet by approxi mately 4-8% per 1% flow rate of water relative to air flow rate at an invariable temperature behind the com bustion chamber. An increase in the consumption of the working medium due to the evaporation of injected water and the formation of steam mainly contribute to an increase in power. The specific compression work of the working medium simultaneously decreases due to a decrease in its temperature in a compressor and a decrease in radial spacings between the blades and the case. However, the total power consumed by the com pressor remains approximately the same since the decrease in the specific work is leveled out by an increase in power for the compression of the addi tional working medium (steam) and the necessity to supply additional power to the compressor, which is consumed to evaporate water. The turbine power increases as the temperature before it is retained, but additional fuel supply is required in this case. In this case, the efficiency of producing useful work by the unit almost remains unchanged. An increase in the efficiency of an independent unit with the water injec tion can be attained by utilizing the heat of exhaust gases, notably, by heat regeneration in the GTU cycle [5,6] or with using this heat for the needs of district heating.Abstract-The possibilities of broadening the control range of the gas turbine power unit by water injection into various points of the flow path of its compressors including compressed air are analyzed. The results from experimental investigations of a turbine of 1.2 MW capacity are presented.

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