Analysis Of The Energy Consumption In Comfortable Air-conditioning Tains And Research On Energy-saving And Optimization

Along with the rapid development of economy, the challenges of energy andenvironment for our country are more and more difficult, energy consumption of China’ssustainable development as a basic state policy is particularly important. Nowadays, theenergy consumption of railroad train air-conditioning accounts for larger proportion intransportation, and it is increasingly becoming the focus problem. On the other hand, theinternal environment of carriage attracts more and more attention as people living standardsrise, so improvement of the internal carriages’ comfort is also imminent. How to meet thethermal comfort of the passenger and achieve energy-saving has become the core of the airconditioning industry. Solving these key issues is based on the overall analysis of energyconsumption. Aimed at problems mentioned above, we propose a series of measures tooptimize the energy conservation which is testified by modeling and analyzing.1. The establishment of train air-conditioning thermal equilibrium modelsBased on the numerical methods of the energy consumption, the simulation models ofrailway carriage thermal equilibrium have set up systematically by quoting large number ofdomestic and foreign literatures and analyzing the train parameters. The models consist ofoutdoor meteorological parameters model, thermal eauilibriums sub-model of carriage insidewall, thermal eauilibrium sub-model of carriage outside wall, heat transfer sub-model ofcarriage and thermal air balance in carriage. The concept of integrated temperature of carriageoutside has been introduced in this model, which reduces the model’s complexity. At the sametime, unstable heat transfer reaction coefficient method is used in thermal equilibriumsub-model and calculated the hourly temperature of carriage wall by selecting appropriatecoefficients. This paper presents the calculation method and numerical analysis of carriageinside wall thermal equilibrium heat-flow density and heat transfer of inside wall. We canprecisely control the inside temperature and energy consumption during the train operation byiterative calculations, and the accuracy and reliability of the models is verified by the actualmeasurement, which provide a good foundation for the train air-conditioning energy-efficientdesigns.2. Train air-conditioning energy conservation and optimizing measuresUtilizing train thermal equilibrium models, calculate and analysis the effects of factorson energy consumption respectively, including solar radiation, train speed, relative humidity,wind speed of train inside, air infiltration and fresh air. In the meantime, analyzing theexisting problems on the current train air-conditioning system and combining carriage comfort with air-conditioning energy consumption, this paper puts forward optimal measuresbased on PMV-PPD, which provides the theoretical reference for the further improvement oftrain air-conditioning system energy-saving and human thermal comfort in carriage.