Analysis And Research On The Screw Compressor Through Compensating Vapor In The Course Of Compression And Its Oil-injection Parameters

The screw compressor through compensating vapor in the course of compression iswidely applied in today’s industrial production depending on its high refrigerating output,coefficient of performance, wide range of application condition and better mechanicalproperties. Systematic research of compensating vapor in the course of compression isbased on LG20Ⅲ compressor, which has both normal screw compressor systemand thesystem with economizer，and is in favor of contrasting and analyzing of the systems.By analyzing the compression process of the screw compressor through compensatingvapor in the course of compression, the mathematical models of the working process of thecompressor and its oil system are set up according to the energy conservation equations andthermal equilibrium equations and combining with the structure of the system parameters,calculated using EES software development process, and verified the reliability of themodel according to the literature experimental data. Obtained the performance parametersof the system of screw compressor through compensating vapor in the course ofcompression and oil-injection quantity and nozzle diameter of its oil system by simulatingunder the air conditions, the standard conditions and low temperature conditions, using R22,R717and R134a as working fluid. This study simulates the influence on the performance ofevaporating temperature, condensing temperature of the system, and analyzes theinfluences of different conditions, the supply port location, the supply port pressure to therefrigerating capacity, exhaust temperature, electrical power and the COP of the systemaccording to the simulation results, and compares the three refrigerant characteristics indifferent conditions. Based on the simulation results of the mathematical model of thesystem, analyzed the relationship of the oil-injection quality, oil-injection temperature,nozzle diameter and the evaporation temperature.This theoretical study provides a theoretical basis for parameter selection and optimization of the structure of the screw compressor through compensating vapor in thecourse of compression. This study does not involve the study of the relationship betweensupply port pressure, the supply port location, the oil-injection location. But the influencesbetween oil system parameters and the supply port parameters are also worthy of furtherstudy and will be further studied in the follow-up work.