This study investigates the impact of ambient air parameters on the performance of a gas turbine unit (GTU) and evaluates methods for improving its efficiency through compressor inlet air cooling. Particular attention is given to the climatic conditions of Uzbekistan, where ambient temperatures vary widely from –25 °C to +45 °C, significantly affecting GTU operation. The analysis demonstrates that increasing ambient air temperature reduces air density, leading to a decrease in mass flow rate through the compressor and, consequently, a reduction in power output and overall efficiency. Based on ISO standard conditions (15 °C, 60% relative humidity), it is shown that a temperature increase of 10 °C results in an approximate 8% decrease in GTU power. Mathematical relationships describing the dependence of power and efficiency on inlet air temperature are derived and applied to the GTU operating at the Tashkent CHP plant. Three air cooling methods - absorption chillers, natural evaporative cooling, and forced evaporative cooling - are comparatively analyzed. The results indicate that, considering both technical and economic factors, forced evaporative cooling is the most practical and cost-effective solution. The proposed approach enables mitigation of performance losses and enhances the operational efficiency of GTUs under high-temperature conditions.
Keywords
Outdoor Air TemperatureGTUCompressorOutput PowerEfficiency.
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