Study On The Influence Of Air Conditioning Supply Angle On Thermal Environment And Energy Saving Under Heating Mode

With the change of people's living standards,living concepts and living habits,indoor space has become the most frequent place for people to work and rest,work and leisure.Therefore,indoor environment is attracting more and more people's attention.A good indoor environment can meet people's requirements for thermal comfort commonly used to improve the indoor thermal environment is the air conditioning system.In public buildings,the air supply form of the air conditioning system used should not only meet the requirements of heating in winter but also meet the requirements of cooling in summer.so the mix ventilation this way of the combination of changes in temperature air supply is widely used.However,when the hot wind heating in winter,the airflow from the upper part of the room sent out,the effect of thermal buoyancy makes the air flow floating and thermal stratification phenomenon,resulting in poor room heating effect.Therefore,it is necessary to explore how to optimize thermal stratification and make full use of energy to create a comfortable thermal environment,and how to set the air conditioning temperature in daily life to save energy.In this paper,the research is carried out by means of numerical simulation,experimental measurement and questionnaire survey.The research focuses on the indoor air distribution and thermal comfort created by different air supply angles under the one-way air supply mode.Firstly,the corresponding physical model is established in Airpak3.0 according to the actual building model,through the numerical simulation to explore what kind of angle to be able to create a reasonable temperature field,velocity field and the thermal comfort,and the airflow and comfort characteristics under each air supply angle are analyzed.Then using the experimental measured under the same conditions for experiments,the experimentally measured results to demonstrate the accuracy of the numerical simulation and analysis of the advantages and disadvantages of two methods.Results show that sending last winter heating take unilateral way of air distribution,air flow under the effect of thermal buoyancy bent,and the hot air is concentrated near the ceiling surface and cannot mix with the air in the working area adequately.,the change of the Angle can make hot air flow and lower air mixing,the air supply Angle of 45°is the best,followed by 60°,30°,0°and 75°is the worst.Under the working condition of each horizontal temperature difference is not obvious,there are differences in temperature on the vertical direction,in the upper area temperature is higher than the lower regions,the temperature of working condition maintained at 18?²6?,velocity between 0 m/s² m/s,the value of PMV in workspace between+0.4⁺1.0,PPD between 5%²5%,according to specification for?comfort level.At the same time,the simulated data and the measured data are basically consistent,and the error is within the allowable scope of the project,which can prove the accuracy of the simulation.Therefore,Airpak software can be used for the numerical simulation of indoor air flow.Secondly,the thermal comfort questionnaire survey was conducted to explore the thermal environment created by different air supply angles.The results show that,with the change of working conditions,the thermal sensation of the subjects'lower body fluctuates little,and the negative value appears in the initial starting period of air conditioning in some working conditions,resulting in a slightly cool feeling.The thermal comfort of the lower body area cannot be significantly adjusted by the influence of buoyancy.When the air supply Angle is 45°and 60°,the thermal sensation of human body is better than other working conditions,and the thermal comfort of the whole room can be taken into account.When the air flow is too low from the ground at75°,it will bring people a sense of blowing,so it is not suitable for use.Finally,energy saving was explored under the optimal air supply angle,with the fixed air supply angle of 45°and the air conditioning setting temperatures of 26?,24?and 22?,respectively.The exploration was conducted by combining numerical simulation with experimental measurement.The results show that there is little difference in the temperature field created by the three working conditions within the range of 0.1m¹.1m,and the temperature value in the range above 1.1m is increasing,T₂₆>T₂₄>T₂₂,heat mainly gathered in the above space,but still cannot reach the lower space.Through the questionnaire survey of the subjects,it is found that 22?can also meet the thermal comfort requirements of human body.Therefore,the setting temperature of air conditioning in winter should not be adjusted to 26?,it is not much different from that of 22?.this will only result in the waste of energy and the increase of electricity,the results for the usual use of air conditioning to provide a reasonable use scheme.Figure[112]table[16]reference[86]...