Spatial Form Optimization Of National Fitness Center Based On Natural Ventilation Performance

In recent years,with the continuous advancement of national fitness industry in China,National Fitness Centers have begun to emerge in various places.As a new type of sports building,the function of the National Fitness Center emphasizes mass participation and weakens performance,and multiple large spaces inside the building are combined in three dimensions.The high compactness of the spatial layout reduces the joint between the internal space of National Fitness Center and the external environment,which leads to widespread dependence on the air conditioning system.However,natural ventilation in the appropriate season can relieve the huge pressure on the energy consumption of the air conditioning system.Among various design factors of National Fitness Center,the spatial form plays an important role in regulating and guiding the airflow as an interactive medium between the building and the environment.Therefore,it is urgent to carry out research on the spatial form guided by natural ventilation performance in accordance with the space particularity and low-cost operation requirements of National Fitness Center.This research aims to integrate various levels of spatial form elements to construct a natural ventilation system in National Fitness Center,explore the influence of spatial form parameters on natural ventilation performance,and establish a rapid optimization method based on a predictive model to search for the optimal combination of spatial form parameters.On the basis of analysis of the development motivation of national fitness facilities and the basic characteristics of National Fitness Center,the correlation between National Fitness Center natural ventilation has been analyzed from 3 aspects of necessity,feasibility and climate potential.48 typical National Fitness Centers nationwide have been investigated to extract spatial form features;and field measurements on typical National Fitness Center have been conducted to obtain indoor wind environment characteristics.Starting from the 3 aspects of natural ventilation and cooling,improving air quality and sports requirements,the air temperature,air age and wind speed have been extracted as evaluation objectives for the natural ventilation performance of the National Fitness Center.G uided by this goal,in-depth research has been carried out around the mechanism of spatial form elements on natural ventilation performance.Starting from the 4 levels of air inlet,space shape,vertical cavity and air outlet,the spatial form elements that affect the natural ventilation of the National Fitness Center have been classified and analyzed.Based on the morphological analysis method,4 levels spatial form elements of National Fitness Center have been integrated to construct the overall natural ventilation system through a series of operation procedures such as the unit partition of the overall building,the partition implantation of form elements,and the integration and reconstruction of the partition system.In order to verify the effectiveness of the construction process of the natural ventilation system in the design stage,the practical discussion has been carried out in combination with typical cases of the National Fitness Center.Using computational fluid dynamics numerical simulation meth od,a series of simulation analyses have been carried out on the geometric control parameters of the natural ventilation system of the National Fitness Center.The basic experimental model has been established based on survey statistical data,and 15 basic geometric control parameters of 4 levels spatial form elements have been extracted to establish the parameterized model.Flunet software has been used to conduct the batch calculation of air temperature,air age and wind speed values.The controlled variable experiments has been used to carry out local sensitivity analysis to explore the influence trend and action law of the single parameter on natural ventilation performance.The parameter correlation method has been used to carry out global sensitivity analysis to explore the influence of multiple parameters on natural ventilation performance,and to calculate the sensitivity index of each geometric parameter.In order to realize the rapid optimization of spatial form parameters of National Fitness Center,a natural ventilation performance prediction model has been established based on the response surface method to replace the complex process and time-consuming CFD numerical simulation.The genetic algorithm has been used to call the response surface model for multi-objective optimization to quickly obtain the optimized solution set,so as to provide effective support for the spatial form design decisions in the design stage.In addition,an optimized platform for the collaborative work of various functional modules has been built,and an interaction interfaces easy to operate has been developed.Combining the results of sensitivity analysis and multi-objective optimization,the spatial form design strategies have been proposed based on natural ventilation performance.The construction process of the natural ventilation system of the National Fitness Center has been established based on the morphological analysis method.The law of the influence of the spatial form parameters of the National Fitness Center o n the natural ventilation performance has been revealed,and the sensitivity index of parameters has been determined.On this basis,the natural ventilation optimization model based on response surface has been proposed to realize the rapid optimization of the spatial form under the guidance of natural ventilation performance,and the design strategies of the spatial form have been proposed.This research can enrich the method system of natural ventilation design for large space sports buildings,update the process and method of natural ventilation performance optimization,and help realize the low-cost sustainable operation of the National Fitness Center.