A Decision-making Assistant Model For Intelligent Fault Management Lin Complex HVAC Systems Using BIM And Sensors

Operation and maintenance management is an important part of engineering project management.The research show that 85%of the life cycle cost of a building occurs after the completion of the construction,that is,the operation and maintenance management stage.For large commercial buildings,heating,ventilation and air conditioning(HVAC)system monitoring and maintenance is the main task in the operation and maintenance management stage.HVAC system's high efficiency and trouble-free operation can not only reduce the energy consumption of buildings,but also have a positive impact on the sustainable development.It can also provide comfortable and healthy living environment for building occupancy and reduce the operation and maintenance costs of enterprises.With the rapid development of the construction industry and the increasing demand for indoor environment,the volume and complexity of HVAC systems are increasing.The promotion of intelligent building concept and the continuous maturity of building automation technology can detect HVAC system's operation status arid realize automatic fault alarm to a certain extent,but it is difficult to detect faults related to HVAC system working efficiency.The timeliness and accuracy of fault location mainly depend on the work experience of the operation and maintenance managers.Secondly,the HVAC system troubleshooting involves analyzing a large amount of information such as floor space information,equipment product parameters,and equipment operation data.These information are usually scattered everywhere and stored in different storage methods such as paper or electronic documents.Information lose and redundancy are common.In addition,the HVAC system fault location requires the operation and maintenance management personnel to have strong three-dimensional imagination of the building and HVAC system distribution.With the complexity of the structure and volume of buildings and HVAC systems,relying only on two-dimensional drawings,even the experienced operation and maintenance managers can hardly construct three-dimensional space in a short time.These have undoubtedly caused the current situation of inefficient operation of large HVAC system troubleshooting.Therefore,it is necessary to explore new solutions for HVAC system fault handling from three aspects:fault location automation,information integration and visualization.Most of the HVAC system fault detection and diagnosis techniques proposed at current stage focus on identifying component-level faults such as air handling units or variable air volume boxes by constructing complex mathematical models.However,due to the high complexity of those algorithms,workflows and information exchange,it is difficult to be used as decision-making tools to assist operation and maintenance managers.There is little or even no research on the HVAC system fault location method at the overall building level,and comprehensively improving and integrating fault location information.Information visualization and integration are the main features of BIM technology.Since 2005,more and more research has been done to improve the management level of operation and maintenance by applying BIM and sensing technology,but these studies are usually highly targeted and difficult to simultaneously realize data visualization,integration and automatically positioning.There are few studies on the application of HVAC system fault handling.It can be seen that BIM and sensing technology have high application potential in the automatic detection and location of HAVC system faults,and there is much room for research in related aspects.In this research context,this paper proposes an integrated solution based on BIM and sensing technology through a large number of literature research and field visits,and develops a prototype system,that is,the intelligent fault location system.Based on the existing tree structure network fault diagnosis and location algorithm.BIM technology and sensing technology are introduced to expand the HVAC system fault handling ideas and solve existing problems.From the framework of this paper,it is divided into five parts:introduction,related theoretical introduction,intelligent fault location system establishment,case study and conclusion.Firstly,this paper introduces the research background,significance,content,research methods and innovations.Secondly,it introduces the related concepts of HVAC system,sensor and automatic detection technology,BIM and tree structure network fault diagnosis and location algorithm,that is,FLoc algorithm.To lay a theoretical foundation for the construction of the intelligent fault location system below;after that,the HVAC system fault detection and positioning method framework is proposed,and the function and development method of each module are explained in detail.Finally,the experiment was carried out to test the intelligent fault location system,and the application prospects of BIM and sensor integration solutions were evaluated through group discussion.The evaluation results contributed to the research practice and theoretical contribution,limitation and future worksDifferent from the research direction of HVAC system fault inspection at present,this paper focuses on applying BIM and sensing technology to HVAC fault handling work.From the perspective of operation and maintenance management,it improves information integration,visualization,positioning automation at the overall building level.Field visits to operation and maintenance managers and on-site testing of prototype systems can understand the problems and the application potential of BIM and sensing technology in HVAC system fault handling work,and the degree of efficiency improvement of HVAC system troubleshooting in tlree aspects:information integration,visualization and fault location automation from a deep level.It can provide reference for the promotion and application of BIM and sensing technology in HVAC system fault handling.