Авіаційно-космічна техніка та технологія (Jan 2020)
COMPARISON OF CHARACTERISTICS OF DEEP AIR COOLING AT THE GTU INLET IN DIFFERENT CLIMAT TYPE
Abstract
The efficiency of deep air cooling at the inlet of gas turbine units has been investigated for changed climatic conditions of operation during the month. For air cooling, the use of waste heat recovery chiller has been considered, which transform the heat of exhaust gases of gas turbine units into the cold. The efficiency of air cooling at the inlet of gas turbine units to different temperatures has been analysed: to 15°C – an absorption lithium-bromide chiller, which is used as the first pre-cooling stage of ambient air and down to 10°C – a combined absorption-ejector chiller, with ejector refrigerant chiller as the second stage of air cooling. The air cooling efficiency is estimated for different climatic conditions: a temperate climate on the example of Odessa (Ukraine) and a subtropical climate for Guangzhou (China). The subtropical climate peculiarity of Guangzhou is the high relative humidity of the air, respectively, and its moisture contents at the same time its high temperatures. As an indicator, when evaluating the efficiency of air cooling at the inlet of gas turbine units to 15°C in an absorption lithium-bromide chiller and deep cooling of air to 10°C in a combined absorption-ejector chiller, the specific fuel consumption reduced has been used. In this case, the needs for specific production of refrigeration capacity and specific capacity of cooling towers for cooling waste heat recovery chillers when cooling air to different temperatures are compared. It is shown that, through extremely different thermal and humidity parameters of ambient air, its cooling at the inlet of gas turbine units to 10ºС for the climatic conditions of Ukraine provides the current decrease in specific fuel consumption due to deeper cooling of the air at the inlet of the GTU in 1.6 ... 1.7 times compared with cooling to 15ºС, and for climatic conditions of the PRC - 1.4 ... 1.45 times. However, it should be noted that a deeper cooling of the air at the inlet of the gas turbine unit to a temperature of 10°C in a combined absorption-ejector chiller compared to its traditional cooling to 15°C in an absorption bromine-lithium chiller requires an increase in the required specific amount of cold by 1.7 ... 2, 0 times and the required specific capacity of cooling towers for cooling chillers by 2.6 ... 3.0 times for the climatic conditions of Ukraine, while for China - 1.25 ... 1.3 and 1.5 ... 1.6 times, respectively.
Keywords
