Analysis and Semiempirical Prediction Method of Moisture Dissipation in High Humidity Environment of a Hydropower Station's Tailrace Surge Tank
The indoor environment of the tailrace surge tank of underground hydropower station is constantly high in humidity.Reasonable dehumidification of the tailrace surge tank and ensuring the safety of indoor personnel and unit equipment have become key issues that need to be urgently addressed.Among them,the analysis and prediction of indoor moisture dissipation in the tailrace surge tank is an essential step in carrying out dehumidification work.Based on measured data,theoretical derivation,and numerical analysis,this article summarizes the variation patterns of various air parameters in the tailrace surge tank of a hydropower station,calculates and compares the moisture dissipation from short-term and long-term tests,determines the influencing factors of convective mass transfer coefficient(based on the difference in air moisture content)in large space in high humidity environments,and establishes a moisture dissipation prediction model for the tailrace surge tank of a hydropower station.The results show that from the end of November to January of the following year,under the condition of low inlet wind speed,the inlet air temperature rises by 1.5～2.2°C to the outlet after heat exchange with the surrounding rock.The inlet low humidity air is close to saturation when it reaches the outlet.The moisture dispersion in the tailrace surge tank is a dynamic change process,which peaks at 28～32g/(m2·h)at the end of November and drops to 7～10g/(m2·h)in January of the following year.In this paper,it is found that the convective mass transfer coefficient is regarded as a two-factor function of wind speed and moisture content difference,which has a high correlation,and the fitting calculation formula is given.
undergroundhigh humidity environmentmoisture dissipationconvective mass transfer coefficient
万方数据
维普
