Experimental Study On The Impact Of Suction Air Parameters On The Performance Of Air Compressor System

Air compressors are widely used in various industries,and their energy consumption accounts for a large part of the total energy consumption of industry.To solve the problem of energy saving in industrial compressed air system,it will be of great value to improve and develop the energy-saving operation of air compressors.There are two problems to be solved in the research of energy saving of air compressor.Firstly,the influence of inlet air temperature and humidity on the performance of air compressor and its quantitative description.According to the theoretical formula of calculating compressor power consumption in engineering thermodynamics,the energy saving obtained by cooling temperature can be calculated,but for the whole compressed air system,the energy consumption of the system can not be reflected by the upper formula.The effective output work of the air compressor is obtained by test and calculation.Second,the coupling effect of inlet air temperature and humidity on the performance of air compressor.The control variable method is a common method to study the effect of temperature and humidity on the performance of air compressor,but it can not reflect its comprehensive effect at the same time,and lacks the quantitative theoretical relation between temperature,humidity and energy efficiency.Therefore,this paper takes 11 kW screw air compressor as the research object,taking the influence of inlet air parameters on the performance of the air compressor as the research content,aiming at the problems in theory and practice,carries out systematic experimental research and theoretical analysis.First of all,based on the principle of optimal test scheme design to improve the air compressor performance test method.The test principle equation of energy consumption and efficiency of compressed air system is defined,and the quantity to be tested is determined.Based on the main effect factors of test error and the control method of test error,the instrument and instrument are selected,and the performance test bench of air compressor is designed and built.It provides the material basis for solving the air compressor performance parameters with high precision from the test level.Secondly,based on the established test system,the performance parameters of the air compressor are tested,and the effect of inlet air temperature and humidity on the performance of the air compressor is quantitatively studied according to the test principle equation.By means of the comparative analysis method of constant inlet temperature and equal inlet relative humidity,the change of specific energy and total efficiency of air compressor is studied when the inlet air parameters change.The results show that under the exhaust pressure of 0.6MPa,when the inlet relative humidity is 39.7%,the specific energy of the compressed air produced by the air compressor increases by about 5.3%,and the total efficiency decreases by about 5.3% with each increase of the inlet temperature by 10℃.Correspondingly,when the relative humidity at the entrance is 34.4%,the specific energy is increased by 6.8% and the total efficiency is reduced by 6.1%.When the inlet temperature is 6℃,the specific energy of the 1kg compressed air produced by the air compressor increases by 3.0% and the total efficiency decreases by 2.8% for each increase of the inlet relative humidity.Accordingly,when the inlet temperature is 24℃,the specific energy is increased by 2.3% and the total efficiency is reduced by about 2.3%.Finally,the relationship between temperature,relative humidity,specific energy and total efficiency is established.The correlation coefficients of the fitting formula are 0.964 and 0.951,respectively.The deviation between the theoretical calculation value of the specific energy and the total efficiency of all the data and the test value is less than 3%.(The temperature range is:-5.7℃ ~ 30.1℃;and the relative humidity range is: 25.3% ~ 77.9%).The energy consumption of the air compressor can be reduced effectively by reducing the suction temperature and relative humidity.