Optimum Distribution of Two Different Phase Change Materials between Various Components of Roof Air-Conditioned Room, Suitable to Reduce Annual Energy Consumption

Obviously, the outside annual climate change caused either by a major solar input during the hottest period or by a temperature drop during the coldest period leads to discomfort in inside buildings. This effect can be reduced by storing heat transmitted in phase change materials (PCM) as latent heat, in order to ensure a good situation of thermal comfort during all months of the year. In this work, thermal behavior of two roofing systems is studied. One roof is constituted only by usual materials in building. In the other, two phase change materials (PCM) are introduced according to three configurations. Study is interested to assess incorporation effect of two PCMs within the roof and to evaluate the optimum locations to reduce the energy consumption of air-conditioned room. Mono-dimensional numerical model validated analytically and experimentally, is used to carry out a parametric analyzes to determine characteristics of the layers in which the roofs are formed regardless of external climate effect. Numerical calculations are performed for three configurations of roof. Results show that insertion of phase change materials in roof provides best energy consumption saving regardless annual climate change. Generally, the three configurations lead to different results, depending on the combination of PCMs. This difference becomes less important when selection of PCMs take account the thermal comfort level and temperatures of hottest and coldest periods.

The Application of Solid Waste in Thermal Insulation Materials: A Review

As socioeconomic development continues,the issue of building energy consumption has attracted significant attention,and improving the thermal insulation performance of buildings has become a crucial strategic measure.Simultaneously,the application of solid waste in insulation materials has also become a hot topic.This paper reviews the sources and classifications of solid waste,focusing on research progress in its application as insulation materials in the domains of daily life,agriculture,and industry.The research shows that incorporating household solid waste materials,such as waste glass,paper,and clothing scraps into cementitious thermal insulation can significantly reduce the thermal conductivity of the materials,leading to excellent thermal insulation properties.Insulation materials prepared from agricultural solid waste,such as barley straw,corn stalk,chicken feather,and date palm fibers,possess characteristics of lightweight and strong thermal insulation.Industrial solid waste,including waste tires,iron tailings,and coal bottom ash,can also be utilized in the preparation of insulation materials.These innovative applications not only have positive environmental significance by reducing waste emissions and resource consumption,but also provide efficient and sustainable insulation solutions for the construction industry.However,to further optimize the mix design and enhance the durability of insulation materials,continuous research is required to investigate the mechanisms through which solid waste impacts the performance of insulation materials.

Calculating Method for Influence of Material Flow on Energy Consumption in Steel Manufacturing Process

From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship between material flow and the energy intensity is useful to save energy in steel industry. Based on the concept of standard material flow diagram, all possible situations of ferric material flow in steel manufacturing process are analyzed. The expressions of the influence of material flow deviated from standard material flow diagram on energy consumption are put forward.

Obsolescence optimization of electronic and mechatronic components by considering dependability and energy consumption

Nowadays, rapid technological progress influences the dependability of equipments and also causes rapid obsolescence. The mechatronic and electronic equipment components are mostly affected by obsolescence. A new challenger unit possesses identical functionalities, but with higher performances. This work aims to find the optimal number of components which should be replaced by new-type units, under budgetary constraints. In this work, the new challenger unit is characterized by lower energy consumption and the optimization steps are based on genetic algorithm (GA). The result shows the importance of this type of replacement in order to economize energy consumption and to deal with obsolescence.

石膏基复合相变储能材料的研究进展

建筑能耗、工业能耗和交通能耗是能源消耗的主要方式。其中,建筑能耗约占能源消耗的40%,建筑能耗的持续上升会增加碳排放和加速化石能源的消耗,因此,如何提升建筑材料的保温节能性能逐渐成为建筑材料领域的研究热点。储热技术不仅可以降低建筑能耗,还可以减少环境污染。相变储能材料具有优异的储放热能力,是实现热能储存以及温度控制的重要技术手段,在建筑节能领域具有广阔的应用前景。该文主要综述了石膏基相变储能材料的研究进展;根据石膏基相变材料的不同,分析归纳了石膏基有机相变材料和石膏基复合相变材料;介绍了浸渍法、多孔材料吸附法、微胶囊法等制备石膏基复合相变储能材料的方法和机理及影响石膏基相变储能材料的因素;展望了石膏基相变储能材料的研究方向。

数模联动的多特征工件加工能耗预测方法研究

在实际切削加工过程中材料去除率是不断变化的,现有将其视为恒量的能耗建模方法难以实现能耗准确预测。为了提高切削过程能耗预测精度,提出了一种基于材料去除率的数模联动加工能耗预测方法。首先,基于切削过程刀具与工件的接触关系分析了切入、完全切入和切出阶段材料去除率变化规律,并对相应的加工能耗特性进行了分析;其次,提出了数据驱动的刀具切入,切出阶段加工能耗预测方法,以及模型驱动的完全切入阶段加工能耗预测方法,实现加工过程能耗准确预测;最后,利用实验案例验证了所提模型及方法的有效性,为今后研究能耗预测精度奠定了基础。

nfluence of envelope insulation materials on building energy consumption

In this paper, the influence of different external wall insulation materials on the energy consumption of a newly built apartment in Germany is investigated. Three types of insulation materials commonly used in Germany including mineral fiber, polyurethane, and vacuum insula- tion panel are chosen for the case studies. An energy analysis model is established to clarify the primary energy use for production of the insulation materials and for building space heating. The calculation results show that the energy consumption for insulation material production increases with the insulation thickness, whereas the energy use for space heating decreases with the insulation thickness. Thus, there exists an optimum thickness to get the lowest total energy consumption for each kind of insulation material. The ascending order of the total energy consumption of the three materials is mineral fiber, polyurethane, and vacuum insulation panel. However, the optimum insulation thicknesses for the three insulation materials show a verse order at a certain heat transfer coefficient of the base envelope. The energy payback time （EPT） is proposed to calculate the payback time of the primary energy use for insulation material production. Mineral fiber has the shortest time, followed by poly- urethane and vacuum insulation panel. The EPTS is 10, 19 and 21 years, respectively when the heat transfer coefficient of the base envelope is 0.2 W/（m2.K）. In addition, the simulated results show that the theoretical value and the simulated value are basically identical.

A survey of decorative materials on the energy consumption of mid-rise residential buildings in Mashad,Iran

Polyvinylchloride(PVC)panel is one of the most favorite decorative materials that has been popularly applied as finishing of ceiling in residential buildings.It is about five years that the people incline to redecorate the ceiling of old buildings with PVC panel in big cities of Iran,such as Mashad.In this study,the influence of ceiling PVC panel on the cooling and heating loads of studied apartment were determined by software DeST-h.In addition,the summer natural ventilation of the mentioned apartment is investigated by determining the wind speed into the apartment through the computational fluid dynamics(CFD)software.The evaluation of environment indoor wind velocity showed that most of the apartment space is a comfortable zone.The results of studied building analyses demonstrated that using PVC panel on the ceiling can decline the energy consumption of the penthouse(fifth level)of the investigated building,which is about 3.7%and 7%for studied methods of without and with air layer,respectively.In addition,although the existence of air layer can decline the cooling and heating loads,the increase in air layer thickness did not show significant decrease on building energy consumption.However,the PVC panel is expensive and is not suitable to be used for ceiling thermal insulation,but adding a thin layer of air between ceiling and PVC panel can be a good step toward sustainable building,when the people are inclined to utilize it as a decorative ceiling.

感应加热卷烟烟具用电磁屏蔽材料

本研究采用COMSOL有限元软件仿真能量转换效率随屏蔽材料磁导率的变化规律,结果表明,当μ″=0时,μ'越大,能量转换效率越高;当μ″≠0,则存在μ'与μ″的最佳匹配值。根据仿真结果,选取合适的屏蔽材料,在感应加热卷烟烟具保持谐振状态,且发热体温度满足要求的基础上,采用功率分析仪测试烟具1个工作循环的能耗。测试结果表明:在240~320 kHz频率范围内,采用铁氧体材料,μ'越高,效果越优。当μ'为220时,可将1个工作循环能耗由978.14 J降至833.40 J,能量转转效率提升14.80%。采用纳米晶材料,当μ=2064-j349时,性能最优,1个工作循环能耗可降至811.30 J,能量转换效率提升17.06%,随μ'及μ″的进一步提高,能耗逐渐增大,此规律与仿真结果一致。因此,通过合理选择电磁屏蔽材料可提高感应加热卷烟烟具的能量转换效率。

建筑节能降耗系统相变储能砂浆特性

相变储能材料能够有效降低建筑系统的能耗,将研制的新型相变复合材料掺入到砂浆中制备出相变储能砂浆,重点考察了相变复合材料掺量对砂浆力学性能(表观密度、吸水率、抗压强度、抗折强度和软化系数)和热学性能(导热系数和比热容)的影响。结果表明:随着相变储能砂浆中新型相变复合材料掺量的逐渐增大,试样的吸水率逐渐增大,其余各项参数均逐渐减小。当新型相变复合材料的掺量达到30%时,砂浆试样的表观密度为2 007.6 kg·m^(-3),软化系数为0.87,吸水率为11.65%,导热系数为0.97 W·m^(-1)·K^(-1),抗压强度为25.8 MPa,抗折强度为5.7 MPa,比热容为0.85 k J·kg^(-1)·K^(-1),砂浆试样的力学性能和热学性能均能满足相关标准的要求。研究的新型相变复合材料可以应用于建筑节能降耗系统中,达到降低建筑能耗的目的。

冰鲜展示台用甘露醇相变蓄冷剂的性能研究

为满足相变蓄冷冰鲜展示台的使用要求,选择甘露醇复合溶液作为相变蓄冷材料,其无毒、无害、相变温度为-5.5℃、相变潜热为295.7 J/g。在25℃下实验对比添加蓄冷材料前后运行过程中台面温度波动及耗电量的变化,从而分析系统的节能性和经济性。结果表明:在环境温度25℃下,在统计制冰耗电量基础上,与不制冷冰鲜展示台相比,使用蓄冷材料的冰鲜展示台能够延缓冰融化速度,结合峰谷分时电价机制后耗电量平均降低了37.6%,每年减少用冰13.14吨,节约电费1102元,减少二氧化碳排放1.12吨,项目投资回收期为0.8年。

电池热管理对城市客车能耗的影响

先介绍了电池热管理技术(即电池冷却系统)的重要性,并以电池液冷系统作为研究对象,以国内某地区在营运的城市客车的数据为例,结合电池液冷系统的零部件结构和工作原理,分析了电池液冷系统对纯电动客车能耗的影响,以及由于能耗的增加对单车运营成本的影响。

矿化养护碱激发固废胶凝材料性能与环境影响的综合评价

CO_(2)矿化养护固废胶凝材料可实现固废的多样化、减量化消纳,同时固定封存CO_(2),具有双重减碳效益。为综合考虑材料的力学性能、固碳效果与环境影响,选取抗压强度、固碳率、固碳程度、碳化效率、碳排放和能源消耗为评价指标,设计11组配合比试件进行综合性能的量化分析和评分。结果表明,与标准养护相比,矿化养护碱激发固废胶凝材料的抗压强度和整体固碳效果有显著提升。固废具有优异的减排和降耗优势,但碱激发剂的使用对环境影响较大。当粉煤灰、赤泥和钢渣质量比为7∶2∶1,水固比、碱胶比和水玻璃模数分别为0.28、0.26、1.2时,矿化养护碱激发固废胶凝材料的综合性能最优。CO_(2)矿化养护技术与固废资源化利用相结合可释放巨大的固碳潜能,是推动减污、降碳协同增效的重要举措。

建筑节能设计在工业建筑设计中的运用分析

对建筑工程项目节能设计的可行性进行分析,从水资源节约、土地资源节约、材料节约、保温节能、自然环境利用几方面对建筑节能设计在工业建筑设计中的运用表现进行阐述,并从总体布局设计和房区设计两方面对建筑节能设计在工业建筑设计中的运用途径进行分析探讨。

150万t/a常减压装置标定数据分析

基于某石化厂150万t/a常减压装置的生产现状,连续进行了为期3 d的标定,主要考核装置的实际生产能力,各项参数是否达到设计规定的指标,考核加热炉运行能力、常减压塔的分离能力和产品质量情况以及装置的能量消耗、能耗分布情况等。通过标定分析摸清装置运行情况和不利因素,为进一步优化操作参数提供基础数据,为装置处理量的提高、技术改造、节能降耗等措施提供技术依据。

竹纤维板项目节能降耗研究

竹纤维板是人造纤维板的一种,主要以竹纤维作为原料,其性能相较于以木质纤维或其他植物素纤维为原料的传统纤维板更优秀,可以代替塑料产品进而减少塑料污染,同时进一步深化了“以竹代木、以竹代塑”等绿色环保新理念。文章介绍了竹纤维板的生产流程及用能情况,并提出了在生产过程中的节能降耗措施,例如变频调速技术、伺服电机、余热回收利用、烘干系统节能设计、管道保温隔热及冷凝水回收、蒸汽管道合理布置以及白水回收技术措施。

碳材料烘干过程中的湿度控制策略

随着碳材料在各个领域的广泛应用,对其生产过程中的烘干环节进行有效控制变得尤为重要。湿度控制作为碳材料烘干过程中关键的一环,直接影响着成品的质量、稳定性和一致性。文章旨在探讨碳材料烘干过程中湿度控制策略,以便于优化碳材料烘干过程,提高产品质量、生产效率,并降低能源消耗,同时为碳材料烘干过程中湿度控制的实践提供指导和借鉴,推动碳材料的可持续发展与应用。

严寒地区既有建筑近零能耗改造材料研究

通过实验研究对建筑外保温材料、玻璃幕墙材料、地面和墙面材料、采暖、通风、空调系统材料等进行了筛选和测试。实验结果显示,采用适宜的材料可以显著提高建筑的节能性能,有效降低能源消耗。研究还探讨了材料在不同建筑类型和使用环境下的适用性和效果,并提出了相关建议和实践指导。

烟草生产企业中的自动化烘烤工艺优化与能耗降低策略研究

烟草生产是一个能源密集型行业,烟叶烘烤环节是烟草生产过程中最重要、最耗能的环节之一,传统的烟叶烘烤工艺通常采用人工操作烘烤设备,能效较低,存在着能源浪费和生产效率低下的问题,随着自动化技术的不断发展和应用,探索烟草生产企业中的自动化烘烤工艺优化与能耗降低策略十分重要。文章设计了一套高效的自动化烘烤系统,并采用了多种节能措施。试验结果表明,优化后的烘烤工艺不仅能够显著降低能耗,还提高了生产效率,提升了产品质量。

电除尘器在高砷高硫复杂工况下的优化设计及应用

目前,电除尘器通常是在负压、不腐蚀结晶工况下运行,要突破在高砷高硫复杂工况下不能长期保持正常运行的瓶颈,虽存在一定的难度,但采取针对性的优化设计和材质升级,能有效降低设备故障率,达到长效正常运行的目标。紧随国家政策实现节能降耗、低炭发展,采用高频电源间歇输出,在不降瞬间电场强度的同时对烟气含尘量进行达标收集,降低电能消耗,从而提高企业经济效益。