Study On Solar Ventilation Design In Qinba Mountainous Building

The rapid development of the economic demand more energy,which results a gradually increase trend of the energy consumption.In the energy consumption structure,the building energy consumption accounts for approximately 35% of the total energy consumption.The energy conservation has therefore become a major concern in contemporary society,for the fact of the increasingly serious energy consumption problems.Natural ventilation is an important way to achieve our current stage of building energy efficiency,improve the quality of life,and reduce the morbid building.The ventilation caused by the non-organized natural convection and air permeation is unable to provide the required air flow for a comfortable environment.The most cost-effective ventilation method for the conditions of hot summer and cold winter is the use of solar chimney passive technology,which can not only prevents the heat of the sun outdoors,but also provides the driving force for the passive ventilation technology in the summer.Moreover,the use of solar chimney passive technology can effectively improve the indoor thermal environment in the winter.The strengthen natural ventilation technology by the solar chimney can provide floating force via the solar radiation heat in the summer,convert the heat to kinetic energy,and can therefore draw the fresh air outdoor into indoor rooms in the summer.As a result,the solar chimney can increase the ventilation,remove the indoor surplus heat and wet,and improve the indoor air quality.As for the winter,the solar chimney collector wall absorbs solar radiant heat,which heats the air temperature inside the solar chimney,draws the hot air into the room,and therefore improves the indoor thermal environment in winter.The research group has conducted the spot investigation and measurement on the rural residential buildings in Qinba Mountain area,and found that although the thermal environment of the building was poor,the local solar energy resources are potentially valuable.It is an important measure to promote the sustainable development of residential buildings in Qinba Mountain by the use of solar energy resources,which may solve the problems of ventilation and cooling in summer and heating in winter.The Fluent software is used in this paper.Based on the climatic conditions of Qinba Mountain area,the RNG k-? turbulence model is used in this paper according to the airflow condition,as well as the DO mode for the solar radiation simulation.The effect of the structural parameters of the integrated solar chimney on the natural ventilationis comprehensively analyzed under steady-state conditions based on the SIMPLEC algorithm.The optimal building aspect ratio is proposed herein by combining with the relationship between building energy consumption and building shape coefficient,which is on the basis of the investigation of the integrated solar energy chimney structure with the optimal natural ventilation.The DesignBuilderV3 software is also used to simulate the temperature of the optimized building interior,which validates the rationality of the building structure.The main research results of this paper are as follows:(1)The structure form of the integrated solar chimney used in the Qinba mountain buildings was proposed according to strengthen ventilation principles of the Trombe wall solar chimney and inclined solar chimney.(2)For the 3.0 m high two-story rural residential buildings in the Qinbu mountain area climate conditions,the solar chimney ventilation volume will be the maximum(i.e.,the optimal condition),when the solar chimney width was 0.8m,the import and export width was 0.2m,the second floor of the entrance down tilt was 4o,and the inclined section of the angle was 30 o.(3)The solar chimney ventilation is inversely proportional to the inclination of the chimney.Also found is that the width of the solar chimney influenced the most on the ventilation volume and the speed fields,and the ventilation volume.(4)According to the relationship between building shape coefficient and energy consumption,as well as the relationship between building orientation and radiation,the optimal room length to width ratio of 2:1 was proposed combing with the investigation on the influence of indoor lighting and solar chimney ventilation on the distribution of indoor wind speed.