The Application Of Natural Ventilation In The Underground Hydropower Station And Research On Annual Scheme Of Ventilation And Air Conditioning System

In recent years,in the context of energy-saving and emission reduction,and effective use of natural ventilation to remove the heat of Underground Hydropower Station during operation.Thus,effectively reducing the energy consumption of mechanical ventilation attracts more and more attention of hydropower industry practitioners.According to the real structure of underground hydropower station,most underground hydropower stations have a vertical height outlet shaft or traffic shaft.The natural ventilation is formed by the thermal pressure of the shaft,which is an important research content of this paper,the research results can provide technical reference for ventilation engineering design of similar underground hydropower stations,which has important engineering value.Firstly,according to the actual operation of the ventilation and air conditioning systems of the underground hydropower station in Chongqing in different seasons is measured,the ventilation path of different seasonal conditions of ventilation and air conditioning and the environmental parameters of the main work areas were tested.The actual ventilation paths in the plant under different working conditions are obtained.The ventilation and heat removal ability of underground hydropower station under different seasons and different working conditions are analyzed and compared.Meanwhile,the natural ventilation capacity of underground powerhouse under different working conditions is discussed.Subsequently,based on the classical theory of fluid mechanics,the actual ventilation path impedance of underground hydropower station is calculated.at the same time,the natural ventilation mathematical models of underground hydropower station are established.The main factors affecting the natural ventilation capacity of underground power plants are analyzed.Based on the annual measured data,the inlet air flow parameters of the traffic tunnel are analyzed.Then,compared with the test data of natural ventilation quantity of underground hydropower station,the calculation results of natural ventilation mathematical model quantity under the same working condition are validated.Comparison results show that the error of the natural ventilation mathematical model is very small,within the allowable range of error,so that the established model of natural ventilation is correct and credible.Based on the established model of natural ventilation,the natural ventilation rates in the different operation conditions of generator and different seasons in the underground hydropower station in Chongqing are predicted.Through the predict results,the available natural ventilation amount and utilization conditions in different seasons are analyzed.Finally,according to the prediction of the natural ventilation rate and the ventilation rate in the worst operating condition in the Underground Hydropower Station which conform to the regulations,the fan shaft ventilation systems are reselected.And the optimization scheme of the annual ventilation operation for Pengshui Underground Hydropower Station is put forward : In summer,Natural ventilation+ mechanical exhaust system;In transient season,Natural ventilation(The outdoor temperature is less than 18 ?),Natural ventilation+ mechanical exhaust system(The outdoor temperature is greater than 18?);In winter,Natural ventilation.At the same time,the economic analysis of the optimization scheme and the current scheme shows that the optimization program can save at least RMB 535000 per year,and can save up to RMB 2297000 per year.It is proved that the optimized ventilation operation scheme has great energy saving potential...