汽车冲压件在模具中的定位方式

介绍了汽车冲压件冲模设计及制造过程中的几种特殊定位方式,通过分析各个定位方式的工作原理及结构特点,对其使用范围进行了阐述,帮助模具设计及制造人员快速选用合适的定位方式,以保证模具能够高品质、高效率地生产汽车冲压件。     

环形走廊机械排烟口水平布置对机械排烟效果的影响

以1幢高层建筑环形走廊为例,利用火灾动力学模拟软件FDS研究了环形走廊不同的排烟口水平布置方式对走廊机械排烟效果的影响。定义了排烟效率和排热效率2个定量评价机械排烟效果的指标,计算了各种工况的排烟效率和排热效率,通过与走廊上温度等参数的对比分析证明了这种方法的可行性。研究表明:对于环形走廊,排烟口的开启数量和设置位置对排烟效果具有很大影响,在排烟量一定的情况下,并非开启排烟口数量越多越好。针对本文火灾场景,排烟口设置在走廊的转角处比设置在走廊中间位置排烟效果更好;当排烟口设置在4条走廊的转角处时,火灾时开启适当位置的2个排烟口排烟效果远好于4个全开。     

本原设计观

针对建筑创作在经济快速增长的过程中面临的严峻问题,通过阐述分析建筑乱象及其背后的原因,提出建筑创作应倡导以"健康、高效、人文"为三要素的"本原设计"思想,强调以"全方位人文关怀"为核心观念,最终实现"建筑服务于人"。     

Integrating the rebound effect: accurate predictors for upgrading domestic heating

One particular definition of the ‘rebound effect’ has won acceptance for its conceptual clarity and mathematical robustness: the energy efficiency elasticity of demand for energy services. This is formulated as a partial differential, and its structure enables transformations with price and energy elasticities. However, when considering heating energy efficiency upgrades of homes, the mathematical predictions can be unreliable because these upgrades involve large changes in efficiency, energy and energy services, whereas differential calculus only holds true for very small changes. This could be one reason why existing estimates of rebound effects are so diverse. This paper shows how this limitation can be remedied, using the German housing stock as a case study. A curve of consumption/efficiency for this stock is derived from empirical studies and, based on the mathematical definition of the rebound effect, a rebound effect relation is derived from this. This curve is then integrated over the likely ranges of energy efficiency upgrades that would correspond to the government's policy of reducing consumption by 80%. The model is found to be mathematically coherent, and suggests energy service rebounds of 28–39% for the German stock as a whole if the 80% goal is achieved.     

A pathway for net-zero energy buildings: creating a case for zero cost increase

To have market relevance and gain widespread market adoption, zero energy buildings (ZEBs) will need to be designed and constructed cost-effectively, and preferably without additional costs. An approach was developed to create low-energy buildings without additional construction costs such that it yielded innovation in building technology and integration by the market. A case study of the implementation of this method is presented to provide a data point that ZEBs can be built with zero cost increase. Documenting cost-control best practices and packaging those strategies for adoption by the commercial building sector will help make the business case for ZEBs for mainstream construction and promote market uptake of the innovative technologies and design approaches needed. The holistic implementation of cost-control strategies will enable ZEBs to be designed and constructed on a typical budget. The current state of ZEB economics is evaluated and a path forward is proposed for greater market penetration of ZEBs. By demonstrating how to combine ZEB technologies and design approaches into an overall efficiency package that can be implemented at minimal (zero, in certain cases) incremental capital cost, the domain of ZEB design and construction can be expanded from a niche market to the commercial construction mainstream.     

接触式烟气-水冷凝换热器的热工计算方法

对接触式烟气-水冷凝换热器的换热效率进行了分析,充分考虑影响换热效率的各种因素,包括喷嘴雾化粒径和换热器高度等,给出了接触式烟气-水冷凝换热器的热工计算方法,并制作了线算图。采用所提出的热工计算方法,对具体示范工程烟气-水冷凝换热器进行了设计,供暖季现场实测数据表明,烟气-水冷凝换热器的换热性能达到了预期目标。     

矿井避险空间生氧净化系统研究与试验

为了分析矿井避险空间生氧净化系统性能,根据其功能及工作原理,确定系统由气源装置、汇流装置、控制装置、CO2净化装置及CO净化装置组成。研究确定80人16 h需要15 MPa,40 L医用氧气瓶10个及4.78×105 g JS-1净化药剂,药剂更换频率为1.51 h。密闭模拟试验表明：药剂去除效率与CO2初始体积分数无关,而与风机位置、风机功率及药剂层厚度相关;当风机位于药剂层下方时,最佳风机功率为185 W,最佳药剂厚度为250 mm,CO2去除效率为91%;组合后的生氧净化系统比独立系统提高了CO2净化性能及空间气体均匀扩散能力。现场载人实验证明：生氧净化系统能够保证空间O2体积分数为19.5%,CO2体积分数为0.6%~0.9%。     

综掘工作面降尘效率影响因素试验研究

针对煤矿开采过程中综掘工作面产生大量粉尘的问题,在实验室建立了基于旋流通风的综掘工作面通风系统,并研究了旋流通风系统中压、抽风筒风口位置和压抽比等关键影响因素对综掘工作面降尘效率的影响.研究结果表明:综掘工作面旋流通风系统可在掘进机司机前方形成基本封闭整个巷道断面的旋流气幕,能有效防止粉尘向其他区域扩散.压抽比一定时,适当地按比例增加压入风量和抽出风量有利于改善旋流通风系统的降尘效果.对于断面积12 m2左右的巷道,合理的压、抽风筒风口至掘进工作面距离分别为17 m、2 m;合理的压抽比为0.9 ～1.2.     

提高变电站倒闸操作工作效率的实践

从变电运行管理的倒闸操作和工作许可流程方面出发,探讨了现行制度及实际操作中存在的一些弊端,并对改进策略作了分析,以通过优化流程、加强操作和工作前的准备工作,使变电设备的停电检修工作效率更高,达到减少停电时间和减少现场人员作业时间的目的。     

高效能水环境景观在住区的应用研究

园林景观不仅具有艺术欣赏的价值和功能,它对人们生产、生活及自然环境等更多方面的效能也得到不断挖掘和探讨。该文针对水环境景观的高效能设计以及在住区里的应用进行了研究,反思了我国水资源短缺与高效能水环境未能有效普及的问题,以住区为突破点,探讨高效能水环境景观如何与住区有效结合,对其规划设计的原则和方法进行了归纳总结。