Experimental and numerical analysis of buoyancy-induced flow in inclined triangular enclosures

The buoyancy‐induced heat transfer and fluid flow in a triangular enclosure are investigated both numerically and experimentally. The enclosure is heated from one wall and the adjacent wall is insulated. Hypotenuse of the triangle is cooled isothermally. The numerical tests and experiments covered a range of Rayleigh number, Ra, from 1.5 × 10⁴ to 1.5 × 10⁵. The local and average Nusselt numbers are given for different orientation angles. A code was written based on finite difference method in Fortran platform to solve governing equations of natural convection. Experimental and numerical results show good agreement. It is observed that inclination angle can be used as a control parameter for heat transfer.     

BHP来实轻钢围护系统施工工艺

厦门某工业厂房采用BHP来实轻钢围护系统,屋面无搭接、无螺钉穿透、无压条,防漏可靠,排水能力极佳;并且防热胀冷缩性、隔热、防火、保温、吸声、通风效果好。BHP屋面及墙面的铺装有其特定的工艺和施工要点。在施工中对原设计还进行了部分改进,该厂房至今未出现变形与渗漏现象。     

轻型围护门式刚架普通钢结构厂房的优化设计分析

随着轻型围护材料的广泛应用和一些钢结构厂房工程的实践,在普通钢结构厂房中,用实腹式门式刚架代替传统采用的格构式刚架结构成为可能,但现有设计方法只是单纯采用普钢规范和凭借工程经验。为优化这种设计方法,控制用钢量并保证设计的可靠性,通过对我国现行钢结构相关规范、规程的对比分析,结合工程经验,提出了轻型围护门式刚架普通钢结构厂房的优化设计方法。最后用实际工程案例验证了该方法的可行性和优势,为今后同类型的厂房设计提供了一定的设计依据。     

监测深基坑安全施工的几点方法

通过研究某市轨道交通三号线某站土建工程所采用的基坑动态监测手段,鉴于深基坑的复杂性和不确定性,介绍了测斜仪、钢筋计、土压力计等仪器在深基坑开挖监测中的安装使用方法,以保证基坑工程的顺利进行。     

建筑围护结构节能工程施工质量控制

指出建筑围护结构作为建筑节能的关键环节,其施工质量直接影响整体建筑物的节能情况,根据建筑围护结构施工过程的要点和特点,对施工质量控制进行了阐述,从而确保围护结构节能工程施工质量。     

浅谈建筑节能设计

以降低建筑的空调负荷,实现建筑节能为出发点,结合地区气候特征,从建筑物围护结构入手,阐述了通过改善建筑围护结构的保温隔热性能降低冷热量损失的具体措施,并介绍了环境控制技术、夜间通风等节能途径,以实现建筑节能目标。     

Experimental data and numerical modelling of 1.3 and 2.3 MW fires in a 20 m cubic atrium

Atria and large spaces are common architectonical features in modern buildings such as high rises, auditoria, warehouses, airports and mass transport stations among others. There is currently an international trend towards the performance-based design for fire safety of these building elements. This design process relies heavily on fire modelling but the knowledge in fire dynamics and the movement of smoke in atria and large spaces still presents some gaps. This paper aims at contributing to close these gaps and reports the three Murcia Atrium Fire Tests conducted in a 20 m cubic enclosure using pools of 1.3 and 2.3 MW. Detailed transient measurements of gas and wall temperatures, as well as pressure drop through the exhaust fans and airflow at the inlets were recorded. The study also includes the effect of the mechanical exhaust ventilation. Results have been compared with those predicted by the computational fluid dynamics (CFD) model Fire Dynamics Simulator FDSv4. In general terms, the comparisons between experiments and simulations show good agreement, especially in the far field of the plume, but the accuracy is poor at the lower plume region and near the flame.     

上海既有住宅不同部位的节能效果分析

在上海的既有住宅中有大量的多层住宅及高层住宅,节能减排中的耗电量的探索有较大的空间文中采样了较典型的多层住宅、高层住宅各一幢,对其的各类围护构造作了改造前与后的实体与模拟分析,并作了排序研究,从中探索出各类围护构造茬改造时的化化效果,并也指出可能存在的不足之外。     

大型深基坑自立式围护结构的设计和施工

采用双排灌注桩加环压梁形成基坑围护，辅以分段开挖、外围卸土的措施，使深基坑施工有了安全保证。     

Hold Time Calculations for Non-Standard Enclosures

Current methods of calculating hold time for a fire fighting gas assume that the enclosure is of uniform horizontal cross-sectional area and has horizontal upper and lower boundaries (a standard enclosure). The paper shows that the hold time equation for continuous mixing in standard enclosures may also be used for non-standard enclosures, presents exact and simplified equations for descending interfaces in non-standard enclosures, and discusses the accuracy of the simplified equation. Considering the error when the simplified equation is applied to standard enclosures, and that it is always conservative for an enclosure of any shape, it is suggested that it may be used as an approximation for non-standard enclosures. The paper also presents a hold time equation for a descending interface in a standard enclosure with laminar flow in the leaks.