Simulation Study Of Office Buildings Thermal Comfort Under Stratum Ventilation

Countries around the world are facing the impact of the energy crisis and the greenhouse effect,and the implementation of measures to save energy and reduce emissions is imminent.Under such circumstances,in order to cope with this problem,many regions have proposed a higher summer air-conditioning interior design temperature to deal with the energy consumption of air conditioners.In general,if the goal of energy saving needs to be achieved,then Thermal comfort will be unsatisfactory,because in order to achieve a more comfortable indoor environment,you need to consume part of the energy to maintain this environmental standard.From this level as a starting point to explore,stratum ventilation as a new type of ventilation has attracted widespread attention in recent years.Research shows that this type of ventilation can effectively solve the contradiction between energy saving and comfort.In the context of energy saving,many governments in the East Asian region have introduced a new summer air-conditioning temperature policy,which is to increase the air-conditioning temperature.To implement a high-temperature air-conditioning solution,it is necessary to make a good air supply system under such conditions,so that it can not only perform in a higher temperature environment,but also take into account indoor air quality and personnel heat comfort.The new type of air supply proposed by the researchers,that is,stratum ventilation,can send the treated fresh air layer directly to the working area of the human body,and appropriately increase the temperature of the air supply to achieve the same thermal comfort conditions for the human body.The proposal of this air supply method can not only alleviate the problem of air conditioning energy consumption,but also improve the indoor air environment,and has a wide range of applications and research prospects.In order to do further research and explore the superiority of the room in the stratum ventilation mode,this article will carry out the simulation of the stratum ventilation.This article uses Airpak software to investigate the indoor thermal comfort of a typical office room in Tianjin.By establishing a mathematical model and a physical model for a typical office environment,and simplifying the model appropriately,the RNG-εtwo equation turbulence model is used.Firstly,in the stratum air supply mode,the air supply height of the indoor air supply outlet and the number of air changes are changed respectively for comparative analysis.Through the pollutant concentration,air age,ventilation efficiency and other indicators,explore the impact of different air supply heights on the indoor air environment,and then through the three-dimensional indoor temperature field,velocity field,and pollutant concentration,air age,PMV-PPD Analysis and comparison,for the same air supply temperature and air supply height,the difference in the number of air changes on the indoor thermal comfort environment.Then in the office model,the stratum ventilation,displacement ventilation,and mixed ventilation make relevant simulation comparisons.Under the comparison of various index parameters,explore the superiority of the stratum ventilation method compared with the traditional two ventilation methods.Through the investigation and analysis of the simulation of indoor air distribution in this paper,in the office room with floor ventilation,when the air supply height is selected to be 20 cm higher than the personnel breathing zone,that is,1.4m above the ground,the air quality of the indoor breathing zone is the most excellent.Under the same air supply height and air supply temperature,when the number of air changes is 5 times,it can not only meet the requirements of personnel’s thermal comfort,but also achieve the purpose of saving energy.In comparison with the two traditional ventilation methods,it can be concluded that the stratum ventilation method can provide more excellent air quality and can also play a role in energy saving.In the stratum ventilation mode,the indoor thermal comfort is good,and the air is relatively fresh.It is a better choice for stratum ventilation design.