An Energy-Saving Control Strategy on Central Air-Conditioning System

An energy-saving control strategy based on predictive control for central air-conditioning systems is proposed in this paper. The cold load model is developed to describe the dynamic characteristics of temperature control systems, and then parameters in the cold load model and in the central air-conditioning system model are estimated. Generalized predictive control (GPC) is used to establish an optimization model to minimize the consumption of energy and the control error of temperature. The simulated annealing (SA) algorithm, combined with quadratic programming, is adopted to solve the optimal problem. Contrasted with the simulation of traditional PID control, the results prove the effectiveness of this proposed strategy.

Strategies for Introducing Energy Saving Idea into Residential Planning and Design in Urban and Rural Areas of China

Currently,energy saving design has been conducted on single building but not on the whole residential community in urban and rural areas.So,the paper has proposed energy saving measures for residential planning from the perspective of site selection and layout of buildings.Specific measures are as follows.Firstly,buildings should be constructed on the sunny side and leeside;secondly,buildings on the south should be lower than those on the north;the east side of the building should be open while the west side should be closed;thirdly,climate protection unit should be set;fourthly,buildings should be of northsouth direction primarily,and the main room should be set on the east side and the assistant rooms or passage on the west side in the buildings of east-west direction;fifthly,it should select compact and wellarranged households and the units should not be combined in point and dislocation and jointing.

Conceptual design of energy-saving stripping process for industrial sour water

Sour water contains ammonia,carbon dioxide,and hydrogen sulfides,producing from oil refining,coking,and coal gasification.To reduce the energy consumption in sour water stripping,a novel process is proposed which integrates with the bottom flashing mechanical vapor recompression heat pump(MVRHP)for treating such wastewater.Here,Aspen PlusTM as a powerful set of chemical process simulation software is utilized to investigate the economy and feasibility of the novel process.Comparison of the results of two process simulations,it can be seen that it is possible to reduce the total annual cost by nearly 45%to adopt the novel process,despite the capital investment increase 45%more than the conventional process.Thus,the provided conceptual design will play a guiding role in the industrialization of the process.

Low Carbon Building Design Optimization Based on Intelligent Energy Management System

The construction of relevant standards for building carbon emission assessment in China has just started,and the quantitative analysis method and evaluation system are still imperfect,which hinders the development of low-carbon building design.Therefore,the use of intelligent energy management system is very necessary.The purpose of this paper is to explore the design optimization of low-carbon buildings based on intelligent energy management systems.Based on the proposed quantitative method of building carbon emission,this paper establishes the quota theoretical system of building carbon emission analysis,and develops the quota based carbon emission calculation software.Smart energy management system is a low-carbon energy-saving system based on the reference of large-scale building energy-saving system and combined with energy consumption.It provides a fast and effective calculation tool for the quantitative evaluation of carbon emission of construction projects,so as to realize the carbon emission control and optimization in the early stage of architectural design and construction.On this basis,the evaluation,analysis and calculation method of building structure based on carbon reduction target is proposed,combined with the carbon emission quota management standard proposed in this paper.Taking small high-rise residential buildings as an example,this paper compares and analyzes different building structural systems from the perspectives of structural performance,economy and carbon emission level.It provides a reference for the design and evaluation of low-carbon building structures.The smart energy management system collects user energy use parameters.It uses time period and time sequence to obtain a large amount of data for analysis and integration,which provides users with intuitive energy consumption data.Compared with the traditional architectural design method,the industrialized construction method can save 589.22 megajoules(MJ)per square meter.Based on 29270 megajoules(MJ)per ton of standard coal,the construction area of the case is about 8000 m2,and the energy saving of residential buildings is 161.04 tons of standard coal.This research is of great significance in reducing the carbon emission intensity of buildings.

Shortcut Method of Design and Energy-Saving Analysis of Sargent Dividing Wall Column

The Sargent dividing wall column can implement four products separation sequences in one column based on Fully Thermally Coupled Distillation Column. The initial design parameters are required for the design optimization or dynamic control of the Sargent dividing wall column, and in order to make the rigorous simulation of the Sargent dividing wall column more conducive to convergence, a ten column model for complex Sargent column is established in this paper,and the shortcut design method of this model is proposed. The internal minimum vapor and liquid flow are obtained by the Underwood equations and the mass balance method and the V-min method. The separation for a 4-component shortcut mixture of pentane, hexane, heptane and octane was considered, while the initial values of design parameters and the ratio of vapor-liquid distribution of each column were calculated by using the shortcut design method of a ten column model. And by comparing the shortcut calculations with rigorous simulation results, the practicality and reliability of shortcut calculations were verified. The reason for energy saving was analyzed based on back-mixing. A virtual heat exchanger is proposed to make the Sargent dividing wall column more energy efficient.

Discussion on the application of the concept of environmental protection and energy saving in the design of building water supply and drainage

With the current,our country social economy rapid development,people's living standard and quality of life and therefore have got improved,at the same time,it is the concept of environmental protection and energy saving is also enhanced value,many fields in our country environmental protection and energysaving concept can be seen in the application,especially the application in building water supply and drainage design more widely,to protect the environment,to maximize the use of limited resources,how to reasonable use of water resources in building water supply and drainage construction,above is current the paper mainly discusses the problems in the construction field,this paper based on environmental protection and energy-saving concept,discusses its application in the building water supply and drainage design,for your reference.

Energy performance assessment on central air-conditioning system of commercial building: A case study in China

Energy performance assessment on central air-conditioning system is essential to optimize operating, reduce operating costs, improve indoor environmental quality, and determine whether the retrofitting of the equipment is necessary. But it is difficult to evaluate it reasonably and comprehensively due to its complexity. A "holistic" approach was discussed to evaluate the energy performance of central air-conditioning system for an extra-large commercial building in a subtropical city. All procedures were described in detail, including field investigation method, field measurement instruments, data processing and data analyzing. The main factors affecting energy consumption of air-conditioning system were analyzed and the annual cooling-energy use intensity of this building was calculated and also compared with other shopping malls and other types of buildings in Guangzhou. And COP(coefficient of performance) of chiller, water transfer factor of chilled water system and cooling water system were taken into consideration. At last, the thermal comfort and indoor air quality issues were addressed. The results show that the chilled water pumps are over-sized and the indoor environmental quality should be improved. The purpose of this work is to provide reference for energy performance assessment method for air-conditioning system.

Research on the Design and Energy Saving of New Rural Residential in the Southwest Area

The paper use advantage of local natural resources, greening and sufficient water resources, combine natural ecological environment design with rural architecture, and fully consider local economic base and material technical conditions, and takes site selection and planning, architectural design technology as the two core aspects to study rural residential energy conservation, improving thermal environment of indoor residential that use of nature building energy saving technique, efforts to reduce the use of mechanical equipment system, thereby reducing the rural residential building energy consumption.

Energy-saving Design of Interior Dynamic Ceilings

Interior landscape design reflects human psychological and physical needs on living and working environment, this paper from the perspective of dynamics of interior landscape design and design concept of dynamic ceiling explored the means of meeting dynamic psychological needs of users, and the coordination between interior landscape design and energy-saving design of principal buildings.

Energy-saving Planning and Design of Urban Residential Buildings in Hanzhong Area

Energy-saving design of residential building is an important part of energy-saving architectural design. Planning and design of residential buildings in Hanzhong area should pay more attention to the building orientation, sunshine, summer ventilation and wind resistance in winter and so on, so as to create favorable conditions for energy-saving design of single buildings. The geographical location, climatic characteristics, residents living habits and indoor and outdoor thermal environment situation were analyzed in this paper, and combined with the existing problems of energy conservation in the planning and layout of residential buildings in Hanzhong area. Based on the investigation, this paper drew some conclusions to provide references for the energy-saving planning and design of urban residential buildings in the local area.

Application of Dual Throttling Air-Conditioning System to Explosion-Proof Frequency Converter

An explosion-proof dual throttling air-conditioning system was put forward to solve the heat dissipation and internal dewing problems of explosion-proof frequency converter in the underground coal mine. This study investigated the feasibility and benefits of explosion-proof dual throttling cooling and dehumidification air-conditioning system applied to the explosion-proof frequency converter. The physical model of dual throttling air-conditioning system was established and its performance parameter was described by mathematical method. The design calculation of the system has also been done. The experimental result showed that the system reached the steady state at the refrigeration mode after running 45 min, and the maximum internal temperature of the flame-proof cavity was 31.0 ℃. The system reached the steady state at the dehumidification mode after running 37 min. The maximum internal relative humidity and temperature of the flame-proof cavity were 33.4% and 36.3 ℃, respectively. Therefore, the proposed system had excellent ability of heat dissipation and avoided internal dewing. Compared with water cooling system, it was more energy-saving and economical. The airflow field of dual throttling air-conditioning system was also studied by CFD simulation. It was found that the result of CFD numerical simulation was highly consistent with the experimental data.

Application of Variable Strategies in the Low-cost and Energy-saving Rural Residences in Transitional Areas

Changeful and complex rural family structure and climatic features of transitional areas in China make the application of variable strategy in energy-saving rural residence designs possible.Aiming at the low cost,several effective and reasonable variable strategies were proposed for the design of interior spaces,main bedroom,sunshine room,staircase,west wall,door and window design to satisfy changing structure of a family during different periods and their different thermo-technical requirements in winter and summer.In this way,thermal comfort of rural indoor spaces will be improved,more energy saved,useful experience and thoughts provided for the energy-saving residence design in cold regions and regions hot in summer and cold in winter.

Research and Application of Complete Set Technology of Green and Energy Saving Assembly Building

According to the survey,environmental pollution is serious in China.Air pollution and water pollution are all serious.Therefore,the state pays more and more attention to green environmental protection.The building design is a creative activity in all kinds of energy decreasing,green energy-saving concept becomes an important content of architectural design engineering,green energy-saving design technology with architectural style is the inevitable trend of the development of our country,but also people focus on the problem.This paper analyzes the green energy-saving assembly building,studies the characteristics of the green energy-saving assembly building,and makes a systematic analysis of the green energy-saving assembly technology.

Simplified prediction model for lighting energy consumption in office building scheme design

At the scheme design stage,the potential of daylighting is significant due to the saving for electric lighting use. There are few simple tools for architects to optimize the daylighting design. Therefore,it is useful to develop a design guideline related to the evaluation of lighting energy saving potential and sunlight design strategies. This paper analyzes the impacts of different artificial lighting control methods and design parameters on daylighting. A direct correlation between lighting energy consumption and parameters such as orientations,window to wall ratio (WWR) and perimeter depth is established. A simplified prediction model is proposed to estimate lighting energy consumption with the given perimeter depth,WWR,and window transparency. Validation of the model is carried out compared with detailed lighting simulation software for an office building. After the variation analysis for these parameters,design advises for the daylighting design at scheme design phase are summarized.

Energy-Saving Effect of Discolored Decorative Boards in Flexible Interior Space

Green,energy conservation and environmental protection have increasingly become the theme of the sustained and healthy development of cities against the background of new urbanization,which indicates that the problem of building energy consumption has received growing attention.This paper explores the impact of energy-saving decorations in flexible interior space on energy-saving effect of buildings so as to broaden the horizon of energy conservation in building,thereby alleviating the problem of energy shortage in China.

Synthesis and Design of Distillation Columns for Wide-Boiling Binary Mixtures with Vapor Recompression Heat Pumps

The vapor recompression heat pump(VRHP) distillation technology offers significant improvements in energy efficiency for distillation systems with small temperature differences between the top and bottom of the column. However, the separation of wide-boiling binary mixtures leads to substantial temperature differences between the top and bottom of the column. This limits the applicability of conventional VRHP due to high capital costs and strict performance requirements of the compressor. To overcome these challenges and to accommodate compressor operating conditions, a novel synthesis and design method is introduced to integrate VRHPs with wide-boiling binary mixture distillation columns(WBMDCs). This method enables quick determination of an initial configuration for the integrated WBMDC-VRHP system and helps identify the optimum configuration with the minimum total annual cost. Two examples, namely the separation of benzene/toluene and isopropanol/chlorobenzene, are employed to derive optimum configurations of the WBMDC-VRHP and compare them with the WBMDC. A systematic comparison between the WBMDC-VRHP and WBMDC demonstrates the superior steady-state performance and economic efficiency of the WBMDC-VRHP.

建筑空间最优节能设计模型仿真研究

由于建筑结构主体较多,空间能耗难以合并控制,导致目前建筑空间能源耗用量较大。为此,构建基于等效转换法的建筑空间最优节能模型,并对其仿真研究。提出建筑总体能耗作为初始优化的“尺度”概念,该尺度为建筑空间的外墙、内墙、屋顶、分户楼板以及门窗等参数,求解这些尺度的最佳标准值。采用等效转换法计算在节能条件下所能接受的最大能耗范围。在此基础上,以上述范围值为约束条件,建立控制函数。将上述提到标准尺度值和最大能耗范围设置为最优解,建立最优节能设计模型,设定温差调节因子,对每一次室内外温差实施有效调节控制,保证建筑体参数符合最佳能耗范围。仿真结果证明,所提方法对冬季采暖和夏季制冷的能耗控制效果均较佳,节能效果最优且算法收敛性高,鲁棒性较好。

数控技术在农机零部件加工中的优化及应用

随着农业机械加工及制造行业的快速发展,为了满足农业机械多样化设计要求,数控节能加工技术通过精密的计算机控制,能够实现对农机零部件加工过程中各个参数的准确控制。针对传统农机零部件加工过程能耗大及难以控制的问题,基于带精英策略的非支配排序遗传算法NSGA-Ⅱ对加工工艺参数进行多目标优化,并进行实验对比分析。研究结果对于提高农机零部件加工精度、降低能耗、减少加工时间等提供技术参考与借鉴。

冰上运动建筑曲面光伏参数化集成设计研究

2022年冬奥会成功举办,国内掀起了冰上体育运动的热潮,冰上运动建筑需求量和能源消耗量随之增长。光伏建筑一体化(Building Integrated Photovoltaic,BIPV)作为建筑节能的主要手段之一,在体育建筑屋面具有较大的集成潜力。通过建立寒冷地区曲面冰上运动建筑典型模型进行集成设计研究,基于Grasshopper参数化平台实现新型柔性CIGS薄膜光伏组件沿屋面曲线形态的优化布置,从两个层级出发,提出参数化设计方法与构造措施。通过Honeybee进行能耗模拟,结果表明,该柔性光伏系统全年可以为冰上运动建筑降低15.82%的能量消耗,进而验证了该方案的节能性,为建筑师进行寒冷地区曲面冰上运动建筑设计的节能优化设计提供数据支撑及科学依据。

外窗节能设计与集成技术

建筑外窗作为建筑围护构件中最不节能的部件,包括传热系数(U值)、可见光透射率(T_(vis))、太阳热增益系数(S_(HGC))等在内的光热性能指标直接影响了建筑的能耗。为了更加全面地了解建筑外窗节能设计的关键技术,通过数据库资料详细梳理了前人的相关研究成果。研究发现:窗墙比、建筑遮阳、窗框、窗玻璃、气密性等是影响建筑外窗节能的关键要素;集成技术在外窗节能设计方面具有明显的优越性,能够极大提高外窗的节能效率;人的行为方式对外窗节能效率也会产生较大的影响。