Experimental Study On The Effect Of Direct Evaporative Cooling On Indoor Air Quality

The development of science and technology has brought about an increase in productivity,and people have gone from material poverty to prosperity.However,development has also brought about problems such as air pollution.The problem of haze has been plaguing people,and the demand for clean fresh air has increased.The development of HVAC technology has always shouldered the heavy responsibility of adjusting the temperature and humidity of the living environment and the cleanliness of the air.The new air-conditioning system has the most prominent impact on indoor air.In the application of traditional air conditioning systems,there are problems such as high energy consumption of air conditioners and lack of introduction of fresh air.Direct evaporative cooling ventilation and air conditioning systems are widely used in human settlements due to their low energy consumption and the introduction of fresh air into the room.Direct evaporative cooling not only cools and humidifies the air,but also affects the fresh air cleanliness,thus changing the indoor air quality.Regarding the influence of direct evaporative coolers on air quality,scholars at home and abroad have done extensive research,mainly including two categories:one is to study the impact of this technology on harmful gases in the air,and the other is to study the concentration of particulate matter in the air.Impact.Regarding the influence on the concentration of particulate matter in the air,the current research is mostly concentrated in the experimental stage,and the experimental research is conducted under the condition of single and mostly concentrated dusting,and the effect of direct evaporative cooler on air quality in human settlements There are fewer work,mostly test research,and lack of rigorous experimental research analysis.This paper focuses on the impact of direct evaporative cooling technology on indoor air quality in human settlements.Based on the existing research,it analyzes the influence mechanism of air cleanliness.The aerosol particle size spectrometer is used to study the application of different kinds of fillers.The effect of evaporative cooling equipment on the concentration of particulate matter in the room.Through theoretical analysis,research and testing,and establishment of microenvironment,experimental research found that:?1?Direct evaporative cooling can effectively reduce the particle concentration of R?100?m(TSP,PM₁₀)in the air while changing the temperature and humidity of the air,and the effect on the particles with R?2.5?m is not obvious.?2?When the direct evaporative cooling equipment meets the minimum water spray density of 0.44 kg/?m².s?and the wind speed is 1.5 m/s and 2.5 m/s,the fog is generated during the contact between air and water.The water makes the concentration of particulate matter in the indoor air increase first and then decreases,and the purification efficiency of direct evaporative cooling shows hysteresis.When the wind speed V=2.3 m/s,there is no phenomenon of particulate matter rising.The concentration of particulate matter in the air after direct evaporative cooling is always lower than before the action.?3?Compared with the purification efficiency of the direct evaporative cooling generator with plant fiber filler,metal aluminum foil filler and polymer composite filler,the metal aluminum foil filler has the best purification performance.At a wind speed of 1.5 m/s,the purification efficiency is the highest,the purification efficiency for PM2.5 is 25%,the purification efficiency for PM₁₀0 is 56%,and the purification efficiency for TSP is 58%.When the wind speed is 2.3 m/s,the filtration efficiency is the lowest,the purification efficiency of PM_2.5.5 is 18%,the purification efficiency of PM10 is 50%,the purification efficiency of TSP is 52.5%,and direct evaporative cooling using only air and water is used.The indoor particulate matter concentration also has a purifying effect.Compared with the packed direct evaporative cooling,the purification efficiency of the PM is low,the PM₁₀purification efficiency is 44%,and the TSP purification efficiency is 50%.?4?When the outdoor PM_2.5?100?g/m³,PM₁₀?357?g/m³,the air is processed by a packed direct evaporative cooling device,and the treated air meets the cleanliness requirements.