建筑外墙节能新体系研究
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摘要
建筑节能对节能整体工作的推进意义重大。改进建筑外围护结构的保温隔热性能是建筑节能中非常重要的一步。近年来推广使用的外墙外保温技术获得了较外墙内保温、自保温、夹芯保温等构造形式更好的节能效果,值得进一步研究推广。
本文在研究已有的各种外保温技术后,发现目前外保温技术的设计思路几乎是单一的,均以阻止热传导为目标。故保温效果完全依赖某种导热系数低的多孔轻质材料的必要厚度来达到,导致出现一些普遍存在而难以克服的缺憾。比如:1)很难满足节能65%和更高的节能要求;2)系统的耐久性和面层开裂脱落仍有疑虑;3)多数保温材料和构造的防火性能不佳;4)多数保温材料是潜在的环保负荷;5)没有自主知识产权;6)对隔热、排湿等热工性能考虑不足。毫无疑问,这诸多缺憾制约着外保温技术的应用和发展。
自然界中热量的传递有热传导,对流和热辐射三种基本方式,建筑外墙也不例外。在有封闭空气间层时,三种传热方式中传热量最大的是热辐射,约占传热总量的70%,其次为对流约占20%,热传导最小仅仅占10%。我们没有理由把外保温技术的设计思路局限在阻止热传导这样一个狭窄的领域里。应该针对传热量最大的热辐射这个主要矛盾来考虑和解决问题。所以笔者认为,设计更高效、先进的外保温体系,首先必须紧紧抓住阻绝热辐射这个关键;其次,充分利用空腔中空气(导热系数仅0.02w/m.k)的绝热性能增强冬季保温效果,并且充分利用空腔中空气的对流换热解决夏季隔热问题;而将阻止热传导放到辅助和补充的位置去。
外保温技术的突破和创新发展,必须从思路和概念上来一次革命。
本文提出了“空腔反射绝热表皮构造”新概念,即:建筑外墙除了结构体(骨骼)外,还应该有生态体均有的“表皮”。这个“表皮”是建筑的“环境过滤器”(杨经文语),所以“表皮”应该是独立的构造部分并以恰当的方法连接到结构体上。“空腔反射绝热表皮”就是采用热工学基本原理设计的建筑外墙新型保温隔热方案。它的特点是:利用强反射材料阻绝热辐射,利用可控制的进、排风口使空腔内空气达到保温或隔热效果,必要时再辅助设置多孔轻质材料保温层。
本文研究、建立了一种建筑外墙节能新体系。该体系主要由三个部分构成:1)强反射材料层;2)空气间层;3)干挂墙板。由于反射材料很薄,故保温隔热构造层的自重大幅度减少;在现代工艺条件下,反射材料几乎可以附着在任何材料表面,这就为未来逐步开发各种材质的绝热表皮创造了条件、埋下了伏笔;反射材料大多数都不燃烧,较之目前多用的聚笨类材料在安全使用上有了更大的保障;同时,耐久性和环保性能也好得多。该体系包含了低端和高端的“空腔反射绝热表皮”,可适应不同经济发展地区的条件。该体系工艺成熟、工业化水平高、容易实现,安装也方便快捷。本文还对该体系可能面临的问题进行了讨论并提出了作者的解决方案。
Construction of energy save has a advance enormous significance.Construction to improve the external structure of the insulation is a very important step for the building energy save.In recent years,the effect of exterior walls insulation technology has been proved better than the inside wall insulation,self-insulation and the sandwich structure insulation.It is worthy of further study.
After been studying a variety of thermal insulation technology,the author found most of the thermal insulation technology design is almost a single train of thought -to prevent heat transfer target.It is totally dependent on some kind of insulation effect of a low thermal conductivity of porous light-weight materials to achieve the necessary thickness,giving rise to a number of prevalent and difficult to overcome shortcomings. For example:1) It is difficult to meet energy-saving65%and 65%higher energy efficiency requirements;2)There are still doubts about the durability of the system and the surface cracking off problem;3) The majority of insulation materials and construction have poor performance of fire;4) The majority of insulation materials are the potential environmental load;5) The producer did not have their own intellectual property rights;6) Thermal properties are considered inadequated,such as insulation, rule out the moisture and so on.There is no doubt that this shortcoming of restricting the exterior walls insulation technology and development.
There are three basic ways of nature heat transfer:heat transfer,convection and heat radiation,The wall construction is no exception.Three ways of heat transfer,in the case of closed air layer,heat radiation transfer accounts for about 70%of the total, followed by about 20%of the convection,heat transfer is only a minimum 10%.
We have no reason to be confined in the heat transfer field.The largest thermal transfer radiation should be considered as the main contradiction to solve.Therefore, the author believes that more efficient design,advanced thermal insulation system, must seize this critical block heat radiation first.Then to make full use of the air in the cavity(thermal conductivity 0.02w/m.k) to enhance the performance of winter heat insulation effect.And make full use of the cavity in the air convection to solve summer heat insulation problem.
Innovation and development of thermal insulation technology must revolute from ideas and concepts.
This paper gives the concept of "reflective cavity insulation skin structure".That is to say,it has not only the structure(bone),but also "skin" of building the external walls.The "skin" is the construction of "environmental filters"(Yang Jinwen scriptures),the "skin" should be a separate part of the structure and appropriate ways to connect to the structure of the body."cavity insulation reflective skin structure"is the use of thermal engineering design of the basic principles of building a new wall insulation program.It is characterized by:using strong reflection blocks heat radiation material,using controlled inside and out the mouth so that the exhaust air cavity insulation or insulation to achieve the effect,if necessary,and it can set light porous layer insulation materials.
In this paper,the author research and establish a new system of the exterior walls energy save.The system consists of three main parts:1) strong reflection layer material; 2) air between the layers;3) Indirect fixing method.Because of the reflective material is thin,the insulation layer structure got a significant reduction in weight.In the conditions of modern technology,the reflective material can be attached to virtually any surface.Step by step for the future development of a variety of insulation materials to create the conditions for the skin,Buried a foreshadowing.Reflective material almost no combustion,compared with the use of polystyrene material,has been proved much safer;at the same time,durability and environmental performance is much better. The system includes a low-end and high-end "reflection cavity insulation skin structure",can adapt to the economic development of different regions.The technology of the system is mature,high level of industrialization,easy to install also convenient. In this paper,the author also discussed the system's facing issues and the solution.
本文在研究已有的各种外保温技术后,发现目前外保温技术的设计思路几乎是单一的,均以阻止热传导为目标。故保温效果完全依赖某种导热系数低的多孔轻质材料的必要厚度来达到,导致出现一些普遍存在而难以克服的缺憾。比如:1)很难满足节能65%和更高的节能要求;2)系统的耐久性和面层开裂脱落仍有疑虑;3)多数保温材料和构造的防火性能不佳;4)多数保温材料是潜在的环保负荷;5)没有自主知识产权;6)对隔热、排湿等热工性能考虑不足。毫无疑问,这诸多缺憾制约着外保温技术的应用和发展。
自然界中热量的传递有热传导,对流和热辐射三种基本方式,建筑外墙也不例外。在有封闭空气间层时,三种传热方式中传热量最大的是热辐射,约占传热总量的70%,其次为对流约占20%,热传导最小仅仅占10%。我们没有理由把外保温技术的设计思路局限在阻止热传导这样一个狭窄的领域里。应该针对传热量最大的热辐射这个主要矛盾来考虑和解决问题。所以笔者认为,设计更高效、先进的外保温体系,首先必须紧紧抓住阻绝热辐射这个关键;其次,充分利用空腔中空气(导热系数仅0.02w/m.k)的绝热性能增强冬季保温效果,并且充分利用空腔中空气的对流换热解决夏季隔热问题;而将阻止热传导放到辅助和补充的位置去。
外保温技术的突破和创新发展,必须从思路和概念上来一次革命。
本文提出了“空腔反射绝热表皮构造”新概念,即:建筑外墙除了结构体(骨骼)外,还应该有生态体均有的“表皮”。这个“表皮”是建筑的“环境过滤器”(杨经文语),所以“表皮”应该是独立的构造部分并以恰当的方法连接到结构体上。“空腔反射绝热表皮”就是采用热工学基本原理设计的建筑外墙新型保温隔热方案。它的特点是:利用强反射材料阻绝热辐射,利用可控制的进、排风口使空腔内空气达到保温或隔热效果,必要时再辅助设置多孔轻质材料保温层。
本文研究、建立了一种建筑外墙节能新体系。该体系主要由三个部分构成:1)强反射材料层;2)空气间层;3)干挂墙板。由于反射材料很薄,故保温隔热构造层的自重大幅度减少;在现代工艺条件下,反射材料几乎可以附着在任何材料表面,这就为未来逐步开发各种材质的绝热表皮创造了条件、埋下了伏笔;反射材料大多数都不燃烧,较之目前多用的聚笨类材料在安全使用上有了更大的保障;同时,耐久性和环保性能也好得多。该体系包含了低端和高端的“空腔反射绝热表皮”,可适应不同经济发展地区的条件。该体系工艺成熟、工业化水平高、容易实现,安装也方便快捷。本文还对该体系可能面临的问题进行了讨论并提出了作者的解决方案。
Construction of energy save has a advance enormous significance.Construction to improve the external structure of the insulation is a very important step for the building energy save.In recent years,the effect of exterior walls insulation technology has been proved better than the inside wall insulation,self-insulation and the sandwich structure insulation.It is worthy of further study.
After been studying a variety of thermal insulation technology,the author found most of the thermal insulation technology design is almost a single train of thought -to prevent heat transfer target.It is totally dependent on some kind of insulation effect of a low thermal conductivity of porous light-weight materials to achieve the necessary thickness,giving rise to a number of prevalent and difficult to overcome shortcomings. For example:1) It is difficult to meet energy-saving65%and 65%higher energy efficiency requirements;2)There are still doubts about the durability of the system and the surface cracking off problem;3) The majority of insulation materials and construction have poor performance of fire;4) The majority of insulation materials are the potential environmental load;5) The producer did not have their own intellectual property rights;6) Thermal properties are considered inadequated,such as insulation, rule out the moisture and so on.There is no doubt that this shortcoming of restricting the exterior walls insulation technology and development.
There are three basic ways of nature heat transfer:heat transfer,convection and heat radiation,The wall construction is no exception.Three ways of heat transfer,in the case of closed air layer,heat radiation transfer accounts for about 70%of the total, followed by about 20%of the convection,heat transfer is only a minimum 10%.
We have no reason to be confined in the heat transfer field.The largest thermal transfer radiation should be considered as the main contradiction to solve.Therefore, the author believes that more efficient design,advanced thermal insulation system, must seize this critical block heat radiation first.Then to make full use of the air in the cavity(thermal conductivity 0.02w/m.k) to enhance the performance of winter heat insulation effect.And make full use of the cavity in the air convection to solve summer heat insulation problem.
Innovation and development of thermal insulation technology must revolute from ideas and concepts.
This paper gives the concept of "reflective cavity insulation skin structure".That is to say,it has not only the structure(bone),but also "skin" of building the external walls.The "skin" is the construction of "environmental filters"(Yang Jinwen scriptures),the "skin" should be a separate part of the structure and appropriate ways to connect to the structure of the body."cavity insulation reflective skin structure"is the use of thermal engineering design of the basic principles of building a new wall insulation program.It is characterized by:using strong reflection blocks heat radiation material,using controlled inside and out the mouth so that the exhaust air cavity insulation or insulation to achieve the effect,if necessary,and it can set light porous layer insulation materials.
In this paper,the author research and establish a new system of the exterior walls energy save.The system consists of three main parts:1) strong reflection layer material; 2) air between the layers;3) Indirect fixing method.Because of the reflective material is thin,the insulation layer structure got a significant reduction in weight.In the conditions of modern technology,the reflective material can be attached to virtually any surface.Step by step for the future development of a variety of insulation materials to create the conditions for the skin,Buried a foreshadowing.Reflective material almost no combustion,compared with the use of polystyrene material,has been proved much safer;at the same time,durability and environmental performance is much better. The system includes a low-end and high-end "reflection cavity insulation skin structure",can adapt to the economic development of different regions.The technology of the system is mature,high level of industrialization,easy to install also convenient. In this paper,the author also discussed the system's facing issues and the solution.
引文
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[2]中华人民共和国国家标准.民用`建筑热工设计规范,GB50176-93
[3]中华人民共和国国家标准图集.公共建筑节能构造-严寒、寒冷地区.06J908-1
[4]中华人民共和国国家标准.居住建筑节能设计标准.DBJ01-602-2006
[5]中华人民共和国国家规范.公共建筑节能施工质量验收规程.DB11-510-2007
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