基于BIM技术的绿建设计与施工过程中的能源模拟与优化研究

在全球能源日渐紧俏且可持续发展观念流行的今日,绿色建筑成为节约能源和减少排放的重要手段,在此领域,设计及施工阶段的能源模拟和效率提高任务,显得尤为重要.该研究深入研究应用BIM技术,在生态建筑设计及建造环节中,对能耗使用进行仿真与改善的途径。利用BIM技术,准确模拟建筑能耗情况,以此为基础优化建筑设计细节,旨在降低能耗,提高能源使用效率。本项探讨审视建筑信息模型技术在构造绿色节能建筑设计领域的应用情况,并深入讨论能源仿真在这一领域中的重要作用,依托实例,本研究具体呈现BIM技术在能源效益仿真与提高方面的具体实施步骤。该篇学术论文拟定一整套在环保建筑设计以及施工环节,采用建筑信息模型技术执行能源模拟并优化设计的细致计划,针对此计划的策略及提议进行细致说明。

基于建筑能源模拟的高效暖通系统设计优化研究

本研究旨在基于建筑能源模拟,探讨高效暖通系统设计优化的方法。通过建筑能源模拟工具,我们可以对建筑内部的热环境和能耗进行精确的预测和评估。首先,我们概述了建筑能源模拟的原理和常用软件工具。然后,介绍了高效暖通系统设计优化的理论和方法,包括相关优化算法的综述。接下来,详细阐述了基于建筑能源模拟的高效暖通系统设计优化的步骤,包括模型构建和验证、初始设计方案生成和评估以及设计方案优化和结果分析。通过实施优化算法,我们可以根据设定的目标函数和约束条件,自动生成多个设计方案,并对其能耗和性能进行评估和对比分析。最后,通过研究结果与讨论,我们总结了初始设计方案的能耗和性能评估结果,以及优化设计方案的能耗和性能改进分析。同时,我们还讨论了不同优化算法的效率和准确性,并提出了未来研究方向的展望。本研究为高效暖通系统设计提供了可行的优化方法,有望在建筑设计和能源管理领域产生积极的影响。

基于能源政策模拟模型的广州市2050年实现碳中和的路径研究

在中国快速城镇化进程中,为尽早推动城市层级的碳中和路径规划工作并作出相应行动,须重点关注城市电力、交通、工业、建筑等行业的能源政策目标制定,因此,以广州市为对象,通过构建能源政策模拟模型,设置基准情景、政策情景和碳中和情景模拟广州市到2050年的能源消费和碳排放情况,分析其重点部门的减排潜力,并评估碳中和情景下各项政策措施的减排贡献。结果显示:在碳中和情景下,广州市能源消费将于2030年达峰,碳排放量将于2026年达峰,到2050年全市碳排放将降至848万t,其中有611万t来自交通领域;电力部门的脱碳将是广州市实现碳中和最重要的途径,碳减排潜力由大到小的其他部门依次为交通、工业、制氢业和建筑;累计碳减排贡献最大的5项政策依次为电力系统零碳化、建筑能效标准提升、交通领域生物燃料替代、工业能效标准提升和氢燃料交通工具销售占比提升。

新型电力系统惯量-频率“云-网-端”感知与控制技术展望

在国家碳达峰、碳中和的目标下,建设新型电力系统是电力系统低碳转型的必然趋势。然而随着大规模新能源的接入,电力系统正逐步向高比例新能源和高比例电力电子设备的“双高”趋势发展,未来电力系统将面临严峻的频率稳定问题。为应对新型电力系统惯量-频率安全运行与控制方面的挑战,围绕调频资源优化“云”、实时惯量感知预警“网”和新能源惯量补偿“端”3个维度,阐述了开展新型电力系统感知与控制研究的必要性和技术体系,论述了开展基于系统近实时频率动态预测的调频资源优化配置方法研究进展,探讨了基于同步相量测量单元的全网惯量态势感知及可视化预警技术方法,归纳了基于超级电容储存能量的新能源构网惯量模拟技术研究现状,最后对未来新型电力系统惯量-频率“云-网-端”技术的发展趋势进行了展望。

美国页岩气扩采的结果模拟

10年前人们的传统思想认为，美国将成为一个主要的液化天然气进口国。然而，受页岩气资源快速发展的影响，如今我们都认为美国已经成为潜力出口国之一。这不仅对美国，同时也对世界其他国家有着显著影响。特别是一些天然气出口国的观点已有了质的改变。也就是说，从能源安全的角度来看，俄罗斯、伊朗、委内瑞拉和卡塔尔已经看到他们预计财富的减少。页岩气的发展有效增加了能源全球供应的弹性，并且可以从根本上减少对这些能源出口国的依赖。

临近空间探空飞艇能源系统仿真技术研究

极地区域凭借长时间光照的极昼现象,成为目前临近空间飞艇试验的理想场所。但是临近空间飞行环境复杂,真实环境试验难以模拟,试验样本少,实物试验成本昂贵。开展临近空间能源系统建模与仿真技术,能够快速模拟验证能源系统的整体性能,为构建临近空间预警探测平台一体化综合试验验证平台提供可靠能源保障。通过对临近空间用能源系统建模、仿真及分析,完成了能源系统的仿真框架,设计完成系统的仿真结构与逻辑关系,完成了仿真关键技术的研究,实现了仿真数据的可视化,直观显示了飞艇能源系统运行过程中的状态,实现了实时预测临近空间飞艇太阳能发电与储能耗电状态,为临近空间飞艇的整体应用发展奠定了基础。

Performance analysis of heat pump based on a new solar air-source heat pump heating system

To further improve the utilization efficiency of solar energy and the performance of solar heat pump heating systems,a new heating mode of a solar air-source heat pump（SASHP）is proposed,and the characteristics and performance of the heat pump part of this new heating system are studied.Based on a SASHP with 10 kW,the mathematical model of this system is built,and the characteristics and performance are concluded from the simulation analysis at different environmental temperatures and output water temperatures.The results show that the performance of heat pumps can be greatly improved based on the new SASHP.When the environmental temperature is 7 ℃,the coefficient of performance（COP）of the air-source heat pump（ASHP）can be increased by 26% at most.This paper sets up a base for further study on the heating system with this new SASHP in the heating season.

渗流耦合系统动边值问题特征分数步差分方法

对多层渗流方程耦合系统动边值问题,提出适合并行计算的一类特征分数步差分格式,利用区域变换、变分形式、粗细网格配套、乘积型叁二次插值、差分算子乘积交换性、高阶差分算子的分解、先验估计的理论和技巧,得到收敛性的最佳阶l2误差估计.该方法已成功地应用到多层油资源运移聚集的资源评估生产实际中,得到了很好的数值模拟结果.

A Low-Overhead Energy-Efficient ARQ Protocol for Wireless Sensor Networks

Wireless sensor network(WSN) is a typical kind of low-power and lossy network,in where ARQ(Automatic Repeat reQuest)schemes are often used to improve packets reliability.However,the ARQ related packets may incur significant load and consume more energy.This paper proposes a novel energy efficient ARQ protocol called ARQ+,which uses the nearest-first scheme and NAK aggregation scheme to reduce the amount and transmission hops of the ARQ related packets.Consequently,the energy consumption is significantly decreased.Theoretical analyses of ARQ+ on energy consumption,packet arrive ratio and latency are provided.Performance improvement of ARQ+ is validated by extensive simulations.They both show that ARQ+ has satisfactory energy efficiency,good packets arriving ratio and reasonable average packet delay comparing to traditional ARQ schemes.

Energy-Efficient Transmission Scheme for Mobile Data Gathering in Wireless Sensor Networks

Energy conservation in Wireless Sensor Networks (WSNs) has always been a crucial issue and has received increased attention in the recent years. A transmission scheme for energy-constrained WSNs is proposed in this paper. The scheme, called MIHOP (MIMO and Multi-hop), combines cluster-based virtual MIMO and multi-hop technologies. The multihop mode is employed in transmitting data when the related sensors are located within a specific number of hops from the sink, and the virtual MIMO mode is used in transmitting data from the remaining sensor nodes. We compare the energy consumption of different transmission schemes and propose an algorithm for determining the optimal hop count in MIHOP. A controllable mobile sink that reduces the energy consumed in sensor transmission is also adopted for data collection. The theoretical analysis and the Monte Carlo simulation demonstrate that the proposed scheme significantly outperforms individual virtual MIMO, multi-hop technologies, and double-string networks in terms of energy conservation. The energy consumption levels under the MIHOP scheme are approximately 12.98%, 47.55% and 48.30% less than that under virtual MIMO schemes, multi-hop networks and doublestring networks, respectively.

Numerical simulation of thermal process and energy saving of lime furnace

Based on the principle of thermal balance and material balance of lime furnace, the reaction and heat transfer process mathematical-physical model and the on-line monitoring model of the decomposition rate of limestone were set up. With this model, numerical simulation is used to analyze the effects of operational parameters on the process of lime calcining and to optimize it. By using visual basic program to communicate and program, the centralized management and automatic control of the lime furnace are realized. The software is put into practical production, which makes the lime furnace operate steadily and efficiently, and causes the increase in output and decrease in energy consumption.

Energy and long-term hygrothermal performance of building enclosures based on dynamic environmental simulation test

Dynamic environmental testing is an effective means to study the energy and long-term hygrothermal performance of building enclosures. Southeast University is designing and building a large-scale dynamic environment simulation testing facility. It can simuhaneously and dynamically simulate temperature, relative humidity, infrared solar radiation, UV radiation, and precipitation. A transformation is needed to predict the energy and long-term hygrothermal performance of building enclosures under real service conditions using data obtained from accelerated tests.

Modeling an emissions peak in China around 2030: Synergies or trade-offs between economy, energy and climate security

China has achieved a political consensus around the need to transform the path of economic growth toward one that lowers carbon intensity and ultimately leads to reductions in carbon emissions, but there remain different views on pathways that could achieve such a transformation. The essential question is whether radical or incremental reforms are required in the coming decades. This study explores relevant pathways in China beyond 2020, particularly modeling the major target choices of carbon emission peaking in China around 2030 as China-US Joint Announcement by an integrated assessment model for climate change IAMC based on carbon factor theory. Here scenarios DGS-2020, LGS2025, LBS-2030 and DBS-2040 derived from the historical pathways of developed countries are developed to access the comprehensive impacts on the economy, energy and climate security for the greener development in China. The findings suggest that the period of 2025--2030 is the window of opportunity to achieve a peak in carbon emissions at a level below 12 Gt CO2 and 8.5 t per capita by reasonable trade-offs from economy growth, annually -0.2% in average and cumulatively -3% deviation to BAU in 2030. The oil and natural gas import dependence will exceed 70% and 45% respectively while the non-fossil energy and electricity share will rise to above 20% and 45%. Meantime, the electrification level in end use sectors will increase substantially and the electricity energy ratio approaching 50%, the labor and capital productivity should be double in improvements and the carbon intensity drop by 65% by 2030 compared to the 2005 level, and the cumulative emission reductions are estimated to be more than 20 Gt CO2 in 2015-2030.

Morphodynamic evolution of the Xiaoqing River mouth:a Huanghe River-derived mixed energy estuary

In an estuary,tidal,wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its evolution.In the Huanghe(Yellow) River estuaries and nearby delta,there are many small sediment-affected estuaries with a unique morphology,such as the Xiaoqing River estuary.In this study,we investigated the special evolution and genetic mechanism of the Xiaoqing River estuary by analyzing graphic and image data with a numerical simulation method.The results show that NE and NE-E tide waves are the main driving force for sandbar formation.Sediment shoals have originated from huge amounts of sediment from the Huanghe River,with consequent deposition at the Xiaoqing River mouth.The lateral suspended sediments beyond the river mouth move landward.Siltation takes place on the northern shoreline near the river mouth whereas erosion occurs in the south.The deposits come mainly from scouring of the shallow seabed on the northern side of the estuary.Storm surges speed up deposition in the estuary.Development of the sediment shoals has occurred in two steps involving the processes of growth and further southward extension.Although the southward shift increases the river curvature and length,the general eastward orientation of the estuary is unlikely to change.Processes on the adjacent shorelines do not affect the development of the sediment shoals.The study presents a morphodynamic evolutionary model for the Xiaoqing River estuary,with a long-term series cycle,within which a relatively short cycle occurs.

Tidal Energy Fluxes and Bottom Boundary Layer Energy Dissipation in the Bering Sea

The spatial distribution of the energy flux, bottom boundary layer （BBL） energy dissipation, surface elevation amplitude and current magnitude of the major semidiurnal tidal constituents in the Bering Sea are examined in detail. These distributions are obtained from the results of a three-dimensional numerical simulation model （POM）. Compared with observation data from seven stations, the root mean square errors of tidal height are 2.6 cm and 1.2 cm for M2 and N2 respectively, and those of phase-lag are 21.8~ and 15.8~ respectively. The majority of the tidal energy flux off the deep basin is along the shelf edge, although some of this flux crosses the shelf edge, especially in the southeast of the shelf break. The total M2 energy dissipation in the Bering Sea is 30.43 GW, which is about 10 times of that of N2 and $2. The semidiurnal tidal energy enters mainly to the Bering Sea by Samalga Pass, Amukta Pass and Seguam Pass, accounting more than 60% of the total energy entering the Being Sea from the Pacific.

Simulating Underwater Plasma Sound Sources to Evaluate Focusing Performance and Analyze Errors

Focused underwater plasma sound sources are being applied in more and more fields. Focusing performance is one of the most important factors determining transmission distance and peak values of the pulsed sound waves. The sound source’s components and focusing mechanism were all analyzed. A model was built in 3D Max and wave strength was measured on the simulation platform. Error analysis was fully integrated into the model so that effects on sound focusing performance of processing-errors and installation-errors could be studied. Based on what was practical, ways to limit the errors were proposed. The results of the error analysis should guide the design, machining, placement, debugging and application of underwater plasma sound sources.

Projected Long-Term Behavior of the CO2 Emission Factor in the Electricity System of Uruguay

Estimating CO2 emission factor of the electricity system is a key aspect in the calculation of the baseline emissions for projects certified as CDM （Clean Development Mechanism）, which replace energy from the grid. Currently, Uruguay is driving the expansion of the electricity system based on domestic renewable energies, in addition to replacing oil-based fuels for others with lower emission factors. This implies a substantial change of the generation park in the next decade and of the associated CO2 emissions. In this paper, a calculation methodology of the baseline emissions is adapted for its incorporation in the software SimSEE （Electric Energy Systems Simulator）, which is used for modeling the Uruguayan electric system, and therefore, allows modeling the current energy generator park and the future one. Using this tool, the CO2 emission factor＇s evolution is evaluated in the 2012-2020 period. The 2020 scenario is based on an optimal expansion of the electric system. The results indicate a strong reduction of the emission factor between 2012 and 2020, going from average values （for 100 simulations） around 0.60 tCO2/MWh to 0.15 tCO2/MWh. In this possible future scenario, CDM certification will probably not act as a strong incentive in Uruguay for the development of projects based on non-traditional renewable energies.

Zero-Energy-Buildings in Different Climates： Design Strategies, Simulation and Prognosis METHOD for Energy Demand

The European Directive 2010/31 claims that by 2020 only （nearly-） ZEB （zero-energy-buildings） may be built. To reach this goal, it is pertinent for buildings to be energetically optimized first. The remaining energy demand must then be covered by on-site renewable energies （PV, geothermal, etc.）. With the area of use （energy demand） and the size of the building envelope/estate （renewable energy supply） in competition with each other, the maximum number of building stories will be most likely limited. For 15 different climatic locations worldwide, the energy demand of optimised office rooms has been simulated and compared with the possible renewable energy production on site. For every location, a good correlation has been found between the simulated energy demand and data like heating and cooling degree hours. Correspondent linear equations are given here. As another result, the maximum numbers of possible stories for ZEBS have been derived, being between 3 and 10 depending on the location.

HIGH-RESOLUTION NUMERICAL SIMULATION OF WIND ENERGY RESOURCE IN HAINAN PROVINCE AND ITS OFFSHORE WATERS

With high resolution （1 kin）, the distribution of wind energy resources in Hainan province and over its offshore waters is numerically simulated by using the Wind Energy Simulation Toolkit （WEST） model developed by Meteorological Research Branch of Environment Canada. Compared with observations from eight coastal anemometric towers and 18 existing stations in the province, the simulations show good reproduction of the real distribution of wind resources in Hainan and over its offshore waters, with the relative error of annual mean wind speed being no more than 9% at the 70-m level. Moreover, based on the simulated results of WEST grids that are closest to where the eight wind towers are located, the annual mean wind speeds are further estimated by using the Danish software Wasp （Wind Atlas Analysis and Application Program）. The estimated results are then compared with the observations from the towers. It shows that the relative error is also less than 9%. Therefore, WEST and WEST＋WAsP will be useful tools for the assessment of wind energy resources in high resolution and selection of wind farm sites in Hainan province and over its offshore waters.

Measurement and Simulation of Energy Consumption of Feed Drive Systems

In this study, in order to investigate the power consumption of feed drive system, mathematical models for the single-axis experimental apparatus are developed. This apparatus can be driven by either of ball screw or linear motor and it is possible to change the mechanical properties of such as grease viscosity of the table. Then, the power consumption is simulated by proposed method based on the mathematical model of feed drive systems and the simulated results are compared with the measured results of the experimental apparatus to confirm the validity of the proposed method. In addition, it is clarified that the energy usages of the feed drive system. The energy losses of the feed drive system are divided into the loss of each part and these energy losses are calculated by the proposed method. Then, it is investigated that the influence of the velocity and friction to the energy consumption of feed drive system. As the results, it is confirmed that proposed method can accurately predict the power consumption of the ball-screw feed drive system. It is also clarified that the energy usage for both of ball-screw and linear motor drive systems.