Research On Migration And Distribution Of Particles And Ventilation Volume Measures In Underground Public Kitchen

With the continuous advancement of China’s urbanization process,the development and utilization of underground space has become a general trend.As an important operation of underground space,catering has many hidden problems about indoor air quality.The cooking fumes can not only endanger human health,but also affect the outdoor air quality.Therefore,optimizing control of cooking fumes have great significance to human health and atmospheric environment.The main contents of this study are:The cooking fumes are analyzed in detail,the physical shape,particle size distribution,formation process,diffusion characteristics,and influencing factors of the cooking fumes are studied;the algorithm applied to the kitchen ventilation system and the airflow organization form of the ventilation system are introduced;the implementation of exhaust hood in local operating environment;experimentally test the three airflow calculation algorithms for the concentration of airborn grease in the human breathing area under the airflow rate,verify the suitability of the three local airflow algorithms,calculate and correct the airflow value for the ventilation method used in preliminary design;experimentally study the effect of the air curtain screen with the addition of a jet air curtain and human disturbance on the concentration of oil fumes in the breathing zone under the best algorithm air volume.Through experimental tests,the following main conclusions are obtained:1.The experiment tested the non-exhaust air condition,the actual fan air volume rate in the kitchen and the three local exhaust air volume calculation algorithms(heat balance method,hood size method,ventilation frequency method),and the smoke concentration in the human breathing area was 1.07,0.79,0.78,0.74 and 0.95mg/m3,that is,under the air volume calculation method of the hood,the concentration of oil fume in the human breathing area is the lowest.2.The addition of an air curtain has a positive effect on the control of kitchen fumes: when the jet wind speed is in the range of 0.6m/s to 2.4m/s,the greater the jet wind speed,the lower the concentration of the fumes,and the more effective the fumes control effect it is good;3.Under the same jet wind speed,the fume control conditions without human disturbance are relatively better than those with human disturbance.