Research On The Climate Characteristics Of "Hui Nan Tian" In Guangzhou And Dehumidification Design Of Residential Bathroom

In Guangzhou,there is abundant rainfall and the average annual humidity is high.Especially during the period of “hui nan tian”,the relative humidity is as high as 90% lasting for a long time,which seriously affects the residents' daily life.Through literature analysis,it is concluded that the cause of "hui nan tian" in Guangzhou is: warm and humid air streams from the Bay of Bengal intersect with cold air mass that penetrates south,neither cold air mass nor warm air mass can prevail,creating a quasi-stationary front and causing continuous rain.Continuously,the humidity in the Guangzhou area during this period is extremely high.Once the movement of the two air masses has caused a certain temperature change and the water vapor in the air is close to saturation,“hui nan tian” will appear.Based on this analysis,further analysis is carried out to find out the main cause of wetness during the “hui nan tian” period of the bathroom: The user generates a lot of water vapor during the bathing process,but the water vapor in the outdoor air during the “hui nan tian” period is near saturation,the concentration of water vapor in the bathroom cannot be reduced through displacement ventilation,and the ventilation and dehumidification method fails,causing the interior of the bathroom to be wet and difficult to dry.As the basic conditions for bathroom dehumidification design,the design parameters should be selected in combination with the characteristics of the “hui nan tian” in Guangzhou.This paper compares and selects the methods for processing meteorological data in the domestic and foreign regulations,and obtains the recommended values for the calculation of outdoor design parameters based on the statistics of meteorological data from 1986 to 2015 in Guangzhou: temperature is 19.1°C,relative humidity is 87.5% and wind speed is 1.6m/s.Then from the two perspectives of human health and thermal comfort,the interior design parameters are analyzed,and the recommended values are obtained: temperature is 23°C,relative humidity is 75%,and wind speed is 0.25m/s.This article introduces the domestic and foreign bathroom ventilation design methods,analyzes the ventilation methods used in the dilution principle.A comparative analysis of ventilation methods for total ventilation,residual heat and humid ventilation,and maintenance of residual pressure and their application in bathrooms.Based on the above analysis,the dehumidification and ventilation calculation methods suitable for the dehumidification design of the bathroom are selected.Proposed dehumidification design method combining daily dehumidification ventilation and auxiliary dehumidification during “hui nan tian”.The actual application of the dehumidification method is explained through actual engineering cases.This article briefly analyzes the design of the bathroom humidity control system.In terms of strategy,the goal of controlling bathroom humidity control is achieved by adjusting the wind speed of the exhaust fan and the heating amount of the heater according to the weather characteristics.In terms of basic requirements,three requirements for stability,rapidity,and accuracy are proposed.The above analysis is based on the use of single-chip microcomputer to achieve the exhaust fan speed control,if you do not consider the use of single-chip microcomputer,the bathroom exhaust fan has only start and stop two modes,the heater is no exception.In order to ensure the humidity control of the bathroom without the use of a single-chip microcomputer,a humidity control system based on a two-position control principle is proposed in this paper,that is,only the start-stop of the bathroom exhaust fan and the switch of the heater are controlled,and the mathematical model and process are discussed.