1 Introduction
In recent years, with the sustained development of social economy, the quantity and quality of civil buildings have been greatly improved. HVAC has also become an indispensable basic link in civil buildings, and its design level directly affects the operation of HVAC systems in civil buildings. Therefore, in modern civil building design, how to choose the most reasonable energy resources according to local conditions and optimize indoor HVAC design without affecting the outdoor environment has become the focus and difficulty of civil building design.
2 HVAC design and design in civil buildings
2. 1 HVAC design. HVAC is an important part of architecture, mainly including heating, ventilation and air conditioning, and it is an essential part of modern architecture. In the whole civil building, HVAC design is the most important part, which directly affects the design work of other aspects of the building. Reasonable HVAC design increases the rigor and reliability of the project to a certain extent, and also improves the quality of the project to a certain extent. Especially at present, energy consumption is increasing, and energy conservation has become the future development trend of every industry. In the process of HVAC design, we must also pay attention to the deepening of energy-saving concept and continuously improve the HVAC design level.
2.2 HVAC design features of civil buildings. Different from ordinary buildings, civil buildings are not only complex and comprehensive, but also can flexibly arrange rooms according to their own preferences in the process of living. In this case, in order to meet the living needs of residents to a greater extent, the personality of residents must be fully respected in the HVAC design process. On the one hand, HVAC design should also be closely combined with the flexible design layout of residents, which is convenient for flexible and diverse installation; On the other hand, in the process of HVAC design, residents' personal preferences should be fully reflected [1].
3 Problems in HVAC design of civil buildings
3. 1 HVAC design scheme is unreasonable. At present, there are still obviously unreasonable design schemes in the HVAC design of civil buildings, which leads to the failure of HVAC engineering. Specifically, there are mainly: in the heating design process, designers only pay attention to the setting of indoor thermal devices, while ignoring the entrance devices, leading to design mistakes; In the process of ventilation design pipeline design, the ventilation pipeline is too narrow or the position of the exhaust fan is wrong, which can not be used to reduce wind resistance and achieve the purpose of ventilation.
3.2 The design was not carried out in strict accordance with the Code for Fire Protection of Civil Buildings. In the process of HVAC design of civil buildings, the design must be carried out in strict accordance with the corresponding codes. However, at present, most units in our country do not strictly follow this rule in the HVAC design of civil buildings, so that in the design process, although the air duct has penetrated the firewall, in order to save materials, the units did not install fire dampers; There is also a part of the design, when the air duct passes through the firewall, it has been deformed, but a fire damper is designed. This affects the design quality of HVAC in civil buildings to some extent.
3.3 The air calculation parameters do not meet the requirements of relevant specifications. In the relevant design codes, the parameter values of air calculation are clearly defined, which requires HVAC designers of civil buildings to refer to them in the design process. For example, the bathroom temperature should be kept at around 12℃, and the bathroom temperature should be kept above 25℃. And in the design process, according to the temperature difference in different regions, the designer can take it as a reference in turn and adjust it according to the local actual situation. However, in the process of HVAC design, the relevant designers did not design strictly according to this design parameter, or even did the opposite, resulting in a great difference between the calculated air value and the requirements of relevant codes [2]. In this case, it will have a great impact on the accuracy of the exhaust position of the doors and windows in the building, resulting in the indoor temperature can not be maintained in a constant range.
3.4 The construction conditions are not fully considered. In the process of HVAC design of civil buildings, specific construction conditions should be fully considered. However, in the actual design process, only through simple debugging methods, the relevant units are allowed to design according to the national design standards. In this process, the actual situation of the construction site is completely ignored, so that the construction difficulty and cost are increased in the later stage, and the design effect is reduced to some extent. 3.5 The application effect of various new energy-saving technologies is not good. In the situation of global resource shortage, the design process of HVAC must also fully integrate the concept of environmental protection, reduce the total energy consumption and strengthen the application of new energy-saving technologies. However, at present, there are serious energy consumption and waste in HVAC design of civil buildings in the ancient city, and the importance of energy saving has not been fully recognized. On the other hand, in the design process of HVAC system, the openness to various new energy-saving technologies is not enough, and the utilization rate is relatively low, so the HVAC design still needs further improvement to improve the energy-saving effect [3].
4 Effective measures to optimize the HVAC design of civil buildings
4. 1 Optimize the design scheme. In view of the unreasonable HVAC design in civil buildings, active and effective measures must be taken to optimize the design scheme. First of all, in general, it is necessary to effectively control the safety hazards in the HVAC design process to ensure the reliability and safety of its overall design; Secondly, in the process of HVAC design, all departments must be protected to ensure the safe operation of each design part; Finally, all personnel involved in HVAC design should not only have high professional quality and comprehensive quality, but also have a strong sense of responsibility and enthusiasm for work. Only in this way can we ensure that the staff can fully grasp the different characteristics of each link in the design process, so as to avoid any problems.
4.2 Optimize the design of HVAC system. First, the design of air conditioning system. On the one hand, the air conditioning system should have good regulation function. Affected by external environmental factors, residents have different requirements for indoor temperature, so the air conditioning system must meet the good adjustment function in the design process; On the other hand, in the process of air conditioning system design, it is necessary to adapt to the actual situation of the building. Especially in civil buildings, the operation time of air conditioning is mostly concentrated in the daytime, so the design results must conform to the characteristics of civil buildings. For example, when designing the air conditioning system of this project, the calculated cooling load of the air conditioner is about 450kW, and the calculated heating load of the air conditioner is about 300kW. In response to the requirements of energy saving and emission reduction, combined with the site conditions of the factory, the ground source heat pump is used as the cold and heat source in this project. In summer, the refrigerant is 7/ 12℃ cold water provided by the ground source heat pump unit, and the heat medium is 45/40℃ hot water provided by the ground source heat pump unit in winter. Adopt indoor fan coil air conditioning system.
The highest point of the system is equipped with automatic exhaust valve, and the lowest point is equipped with drainage device. In return pipe, galvanized steel pipes are used, and flexible foam plastics are used as insulation materials for pipelines, and their fire protection rating is difficult to burn B 1. UPVC pipes are used for condensate pipes, and flexible foam rubber insulation pipes are used for pipeline insulation materials. The air-conditioning air duct adopts galvanized steel plate, and the soft connection between the coil and the air duct and the air return port adopts incombustible materials. Secondly, ventilation and smoke control design. Ventilation and smoke control design is also a key point in HVAC design of civil buildings. In this project, all-heat fresh air ventilator is used to transport fresh air, which is installed in the ceiling. Each room adopts double-layer louver tuyere for air supply, and a split air volume control valve is installed in front of each tuyere. An electric air valve is added to the outdoor air inlet of the total heat fresh air ventilation unit, which is interlocked with the total heat fresh air ventilator to start and stop; In the smoke control design of this project, the window areas of stairwells, corridors and above-ground rooms meet the requirements of natural smoke exhaust, and natural smoke exhaust is adopted.
4.3 The design shall comply with relevant regulations to ensure the reliability of the design. At present, China has clearly stipulated the HVAC design of civil buildings. In the process of Nantong design, construction enterprises must design in strict accordance with relevant regulations to ensure the reliability of construction design and provide good living conditions for residents. First of all, we should strengthen the research on HVAC design standards, strive to conscientiously implement them in specific design work, standardize the corresponding design work, and accurately calculate the air calculation parameters, so as to make HVAC design more standardized, more reliable and safer; Secondly, in the design process, some special places should be comprehensively considered on the basis of norms and standards and combined with the actual situation of the building, bearing in mind other influencing factors.
4.4 Design should be real-time. In the process of HVAC design, it must be strongly implemented to meet the construction requirements. Before the design, the relevant staff must collect a lot of data, and at the same time, closely combine the actual situation of civil buildings, such as geographical location, space size and other factors, and then carry out all-round analysis before designing the drawings, so as to ensure the rationality, scientificity and effectiveness of the design drawings; Secondly, in the design process, the system diagram, floor plan and floor plan should be coordinated to give full play to their value and provide practical and reliable design information for construction personnel.
4.5 Adhere to the concept of green design and strengthen the application of energy-saving technologies. In the situation of resource shortage, the HVAC design of green buildings must be regarded as a new design concept to reduce energy consumption and finally provide a comfortable and reliable living environment for residents. First of all, in the process of energy-saving design, we should strictly follow GB 50 189-20 15, DB 29- 153-20 14, Tianjin Building Energy-saving Design Standard and GB 565438.
5 concluding remarks
To sum up, HVAC design is an important part of civil buildings, and the quality and level of design directly affect the overall effect of the whole building. Therefore, in the process of HVAC design of civil buildings, it is necessary to study the problems existing in the design and put forward corresponding solutions on this basis, so as to continuously improve the design quality of HVAC and ensure the overall effect of the building.
For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd