Ship Residencial Cabin Ventilation Mode Optimization And Pollutants Removal Research

Ship residential cabin has the characteristics of low and small space,complex structure,high personnel density,high heat and moisture load and serious air pollution,so the air conditioning and ventilation design of ship cabin should not only meet the thermal comfort requirements,but also consider the control of air pollutant concentration.In this paper,how to design the ship cabin and cabin ventilation were studied to improve indoor air quality,including thermal comfort design optimization,cough drops and volatile organic compounds(VOC)spread,and to explore the control effect of air purifier.Three kinds of ventilation forms of cabin top attached air supply,circular plate air distributor and vertical wall attached air curtain are simulated.Thermal comfort analysis showed that traditional ventilation is difficult to cover the multilayer beds,while the optimized personalized-vertical wall attached air curtain can effectively improve the local thermal comfort and energy efficiency.Based on the thermal comfort design,the diffusion process of cough drops in four ventilation ways were simulated,and the elimination effect of cough drops and the risk of infection among residents were compared.The results showed that the elimination of cough drops in cabin top attached air supply was more effective,and the breathing area cleanliness of the residents in personalized-vertical wall attached air supply was relatively high.Therefore,the most suitable air supply form should be chosen according to the actual demand.According to the characteristics of the typical VOC pollution sources wood plates,the release rate of VOC is affected by the thermal and humid environment of the cabins.The variable release rate pollution source model is used to replace the fixed release rate boundary condition,and the internal flow field is combined to solve the problem.The cases of ship office cabin and living cabin were simulated,results showed the necessity of introducing pollution source model in the simulation: Only the increase of air temperature and relative humidity will lead to an increase in indoor VOC concentration of 1.15~2.5 times,and the difference between the other local heat and humidity environment will also affect the concentration of VOC.On the basis of the existing cabin,the air purifier is used to control the pollution.the selection principle of air supply angle of different types of air conditioner was given,the results showed that the independent purifier could achieve better purification effect,and the formaldehyde concentration in the cabin decreased by 43% and 35% compared with the purified air conditioner.,and the vertical cabinet type air conditioner with purification with up-supply and down-return was suitable for the purification type air conditioner,and the effect of formaldehyde removal by increase circulating ventilation is limited.