Laser Measurement and Intensity Evaluation of Intake Swirl in Engine Using a Water Analog

The intake swirl in the cylinder was induced by a swirler which was fixed in one of two intake ports. In order to understand the characteristics of the intake swirl, a transparent water analog was designed which simulated 150 type single cylinder engine. At the same time, the particle image velocimetry was used to measure the flow fields induced by various swirlers in the analog. After measurement, a new method was presented to evaluate the intensity of the intake swirl. Then, when the measured sections, the lifts of valve and the swirlers were different, the calculated results of the flow field were compared.

Characteristics of coseismic water level changes at Tangshan well for the Wenchuan MS_8.0 earthquake and its larger aftershocks

Coseismic water level changes which may have been induced by the Wenchuan Ms8.0 earthquake and its 15 larger aftershocks （Ms〉5.4） have been observed at Tangshan well. We analyze the correlation between coseismic parameters （maximum amplitude, duration, coseismic step and the time when the coseismic reach its maximum amplitude） and earthquake parameters （magnitude, well-epicenter distance and depth）, and then compare the time when the coseismic oscillation reaches its maximum amplitude with the seismogram from Douhe seismic station which is about 16.3 km away from Tangshan well. The analysis indicates that magnitude is the main factor influencing the induced coseismic water level changes, and that the well-epicenter distance and depth have less influence. Ms magnitude has the strongest correlation with the coseismic water level changes comparing to Mw and ML magnitudes. There exists strong correlation between the maximum amplitude, step size and the oscillation duration. The water level oscillation and step are both caused by dynamic strain sourcing from seismic waves. Most of the times when the oscillations reach their maximum amplitudes are between S and Rayleigh waves. The coseismic water level changes are due to the co-effect of seismic waves and hydro-geological environments.

Smoothed particle hydrodynamics modeling and simulation of foundry filling process

A numerical model of foundry filling process was established based on the smoothed particle hydrodynamics（SPH）method.To mimic the constraints that the solid mold prescribes on the filling fluid,a composite treatment to the solid boundaries is elaborately designed.On solid boundary surfaces,boundary particles were set,which exert Lennard-Jones force on approaching fluid particles;inside the solid mold,ghost particles were arranged to complete the compact domain of near-boundary fluid particles.Water analog experiments were conducted in parallel with the model simulations.Very good agreement between experimental and simulation results demonstrates the success of model development.

Analog modeling of sand slope stability with different precipitation conditions

Water–sand flow triggered by rainfall is the dominant mechanism for instability and failure of sand slopes. To further analyze the stability state of sand on a slope under different rainfall conditions, the initiation conditions and flow characteristics of water–sand flows are studied. Based on the theory of equilibrium forces and hydrological dynamics, a 1：100-scale analog model is built and verified with field observation data. The results indicate three dynamic stabilization stages of the sand slope under different weather conditions： dry sand, wet sand, and water–sand flow. Water–sand flows are triggered easilyunder short duration and heavy rainfall conditions. The rainfall threshold required to initiate water–sand flow is 4.14 mm/h. Rainfall amount and duration required to initiate water–sand flow decrease with fine sand content increasing. A sand head that develops at the front of the water–sand flow results in a flow along the edge of the sand debris flow and a ‘‘tree root’’ flow morphology. Modelingresults are consistent with theoretical analysis and field observations.

Modeling of unsteadiness of fluid flows and level fluctuations in thin slab continuous casting moulds

Unsteady fluid flows and level fluctuations in a thin slab continuous casting mould have significant influence on product quality. In this study, the phenomena concerning transient flow features and free surface motions were analyzed by means of the large eddy simulation （LES） software with the smagorinsky SGS model--VisualCast （VCast） II, where the Simpler algorithm on a body-fitted mesh was used to resolve governing equations. A series of water analog experiments on the fluid flow and the surface wave in the moulds of thin slab continuous casting were also performed. The results of fluid regions, middle of vortex and level fluctuation from digital simulations were identical with the results of the water analog experiments.

WATER TRANSPORT IN WOOD PARTICLE MATERIAL

An analogy between water flux and the field of temperature gradient in a column of wood fuel chips was discovered by these experiments.The heat-mass transfer coeffieient was deter-mined by least squares method.An equation relating water flux and tempetature gradient was devel-opcd and it was demonstrated that the tempeature gradient was the main driving force for watertransport.The meehanism was evaporation-condensation of water vaor through natural convcctionin air phase.The study gives a theoretical exlanation for analyzing the problem of water transport inwood particle material.

Discovery of a geomorphological analog to Martian araneiforms in the Qaidam Basin, Tibetan Plateau

Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars.A gas erosion process driven by the seasonal sublimation of CO_(2) ice was proposed as an explanation for their formation,which cannot occur on Earth due to the high climatic temperature.In this study,we propose an alternative mechanism that attrib-utes the araneiform formation to the erosion of upwelling salt water from the subsurface,relying on the identification of the first terrestrial analog found in a playa of the Qaidam Basin on the northern Tibetan Plateau.Morphological analysis indicates that the structures in the Qaidam Basin have fractal features comparable to araneiforms on Mars.A numerical model is developed to investigate the araneiform formation driven by the water-diffusion mechanism.The simulation res-ults indicate that the water-diffusion process,under varying ground conditions,may be responsible for the diverse aranei-form morphologies observed on both Earth and Mars.Our numerical simulations also demonstrate that the orientations of the saltwater diffusion networks are controlled by pre-existing polygonal cracks,which is consistent with observations of araneiforms on Mars and Earth.Our study thus suggests that a saltwater-related origin of the araneiform is possible and has significant implications for water searches on Mars.

基于RS-ANN的某矿山井下开采防水安全岩柱厚度的确定

水下矿床是难采矿体的一个重要方面,针对某矿山的实际情况,深入分析了该矿的地质资料后,在查阅相关文献的基础上,建立了该矿导水裂隙带高度的粗糙集—神经网络预测模型.在比较了粗糙集—神经网络预测结果、地质详查报告提供的结果及采用经验公式计算的结果后,认为神经网络预测的结果较准确,其结论在该矿水下开采设计中可以采用.在预测的导水裂隙带高度基础上,参考采矿设计手册中的经验公式,并类比其它矿山水下开采的情况,计算出了防水安全岩柱的厚度.此项研究为该矿重新编制开采设计方案和安全专篇提供了依据,同时为矿山安全管理提供了参考.

Study on Sustainable Water Resource Conservation—Toward Deepening of Homo Environmentics

To unlearn the meaning of a sustainable water resource conservation is now an essential issue in using of sustained, sound, and high-quality water in the world. In this paper, a water quality purification by the Schumann frequencies was first considered through the murmuring sound of upper reach at the mountain stream (Kyoto Pref., Japan) regarding the conservation of water resources. Second, water is changing freely and easily accepting the wavelength of all the sounds. We therefore referred to a flow and dynamic equilibrium to realize and understand the water quality purification process. Finally, a “consciousness only Buddhist philosophy” of water quality as an analogical approach was introduced to realize and understand the water purification process. As a result, we have confirmed the water purification capability by Schmann frequencies in an experiment on water quality. And through the experiment, we have realized the importance/significance to find the meaning for a person’s primary meaningless such as 1) meaning connection among life, environment, and economics as a condition of human life, 2) energy, entropy and fluctuation under law of thermodynamics, 3) a metaphor between water quality and mutual possession of the ten worlds based on conscious-only theory, and 4) sense of wonder through the water purification process.

Study on Sustainable Rainwater Resource Utilization—Towards Deepening of Homo Environmentics

This paper mainly investigated the value of the rainwater by introducing a “Logic of Encounter” that is a new logic beyond the logos and lemma through the metaphors which compare the real rainwater to one’s life. A consideration regarding sustainable rainwater resource utilization has been described and the main results are summarized in the paper.

雄安至北京大兴国际机场快线起步区地下段结构抗浮设防水位取值研究

抗浮设防水位直接影响到地下结构的安全与建设费用,在地下结构建设中至关重要,因此,科学合理地确定地下结构的抗浮设防水位具有巨大的社会意义和经济价值。本文以“雄安新区至北京大大兴国际机场快线地下工程段”为研究对象,系统分析了研究区水文地质条件以及地下水位年内年际动态变化规律,利用数值模拟法和类比预测法确定了地下结构抗浮设防水位标高建议值。结果表明,该场地区域浅层地下水水位埋深一般为5.0~20.0m,地下水水位标高一般为–10.0~1.0m。近五年场地浅层地下水水位标高一般为–5~–10 m,埋深一般为3.0~15.0 m,地下水位逐年升高,回升速率约1.0 m/a。地下结构抗浮设防水位标高取值建议取使用期抗浮设防水位采用数值模拟法预测结果。该成果服务了“雄安新区至北京大兴国际机场快线(R1线)”项目场地抗浮设计,为雄安新区重大工程建设项目的抗浮安全设计提供了示范。

大采宽综采工作面导水裂隙带高度探究

为了探究永煤公司新桥煤矿深埋煤层大采宽工作面导水裂隙带高度发育特征,以典型的开采宽度330 m的某工作面为研究对象,建立了深埋煤层大采宽工作面三维工程地质概化预开采模型,采用FLAC3D数值模拟软件对采动覆岩导水裂隙带高度进行研究,发现这种大采宽工作面开采后应力集中程度明显增大。和经验公式类比获得了该工作面导水裂隙带高度取值范围,提出了现行规范中的相关计算公式预计结果明显偏小,已不适合这种地质及开采条件。最后,在其他条件不变仅改变采宽条件下,模拟了7种不同采宽开采后沿倾向和走向导水裂隙带高度发育特征,对比分析发现导水裂隙带高度随采宽增加呈非线性变化,两者之间具有很好的自然对数拟合关系,确定了增加幅度的采宽阈值及其变化特征。

广西河池某矿水文地质特征分析及涌水量预测

以广西河池某矿区为研究对象,通过对矿区相关的水文地质条件进行分析,并采用水文地质比拟法、大井法和修正后大井法公式对矿区涌水量进行预测对比。结果表明:含水岩组之间水力联系密切,断层破碎带裂隙水发育明显,岩溶破碎带对矿床开采影响较大。矿区北、东以及西部为隔水边界,南部为透水边界。地下水径流赋存运移于岩溶裂隙、断层破碎带及岩溶管道中,汇流集中于北东、北西径流带进行排泄。水文地质比拟法的矿区平水期、枯水期及丰水期涌水量分别为18364.72 m^(3)/d、15 893.31 m^(3)/d、79 794.11 m^(3)/d;大井法用裘布依公式预测结平水期、枯水期及丰水期涌水量分别为23 108.90 m^(3)/d、21 044.15 m^(3)/d、27 418.04 m^(3)/d;修正后的大井法平水期、枯水期及丰水期涌水量分别为16 028.25 m^(3)/d、15 421.58 m^(3)/d、23 485.05 m^(3)/d。研究表明水文地质比拟法和修正后大井法公式预测结果更准确合理,符合预期结果。

隐伏非贯通软弱夹层岩质边坡剪切蠕变特征及稳定性研究

针对隐伏非贯通软弱夹层岩质边坡滑移机理复杂这一关键科学问题。设计一种隐伏非贯通软弱夹层缩尺制备方法,开展考虑夹层埋深、岩层倾角、含水率因素影响下岩体剪切蠕变特性试验。引入多参数岩体渐变损伤变量,分阶段建立剪切蠕变损伤本构模型,并通过相似模拟试验验证模型的合理性,分析此类边坡的稳定性。研究表明:(1)隐伏非贯通含软弱夹层岩体随夹层埋深增加、倾角减小、含水率减小而稳定性升高,反之稳定性降低,且夹层含水率对岩体稳定性影响最大,埋深影响相对较小;(2)考虑多参数渐变损伤本构模型能够反映隐伏非贯通软弱夹层岩体剪切蠕变全过程,且加速蠕变阶段拟合效果优于西原模型;(3)隐伏非贯通软弱夹层缩尺制备方法较为合理,所推剪切蠕变本构模型能够较好拟合边坡蠕变滑移各阶段情况,边坡滑移呈坡脚剪胀、后缘拉裂的整体性滑移,对隐伏非贯通含软弱夹层岩体蠕变滑移具有参考意义。

Optimization research on supply and demand system for water resources in the Chang-Zhu-Tan urban agglomeration

Using system analysis theory and methods, a dynamic model of a water resource supply and demand system was built to simulate trends in the supply and demand of water in the Changsha-Zhuzhou-Xiangtan （Chang-Zhu-Tan） urban agglomeration for the period 2012 to 2030. Four scenarios were examined; namely, a traditional development model, an economic development model, a water-saving model, and a coordinated development model. （i） The problem of balancing water resource supply and demand is becoming increasingly conspicuous with a growing population and a rapidly developing economy. （ii） By 2030, water demand is set to reach a total of 105.1 × 10^8 m^3, with a water supply of 5.4 × 10^8 m^3. A coordinated development model for water resource supply could meet the growing demands of socio-economic development, and generate huge comprehensive benefits. This will be the best solution for the development and utilization of a water resource supply and demand system in the Chang-Zhu-Tan urban agglomeration. （iii） We should accelerate the construction of water conservation projects, strengthen the management of water conservation, optimize economic structures, enhance our awareness of the importance of protecting water resources, hasten the recycling of waste water and environmental improvement, and promote utilization efficiency, and support the capabilities of water resources to meet our expectations.

宝日希勒露天煤矿涌水量预测研究

为有效评估未来矿区水资源供需平衡情况,需精准预测矿区未来矿井涌水量。根据宝日希勒露天矿现有水文地质及充水条件,采用水平集水廊道法、大井法、水文地质比拟法以及水均衡法四种方法对2025年矿坑涌水量进行了预测。结果表明:水平集水廊道法和大井法的水文地质参数选取受人为因素影响较大,预测结果偏大;水均衡法仅能根据矿区水均衡资料进行预测,预测精度不高;水文比拟法对相似性条件要求较高,预测精度较精准。最终根据水文比拟法预测结果确定宝日希勒露天矿2025年矿坑涌水预测水量为185.27万m^(3)/a。模拟分析了矿区采动作用对地下水流场的影响,模拟结果表明,工作面采掘潜水水位最大降深值为50 m。随着工作面采掘的不断推进,地下水降落漏斗面积先增大后保持不变。该研究为矿区安全生产、矿区排水设计以及水资源优化配置提供可靠的数据支撑和技术支持。

河南省某煤矿用水项目取用水合理性分析

【目的】项目区位于丘陵地带,城市供水管网未覆盖,矿区生产及生活仅可以利用处理后达标的矿井涌水。为分析煤矿生产及生活取用水的合理性、矿井涌水可供水量及取水水源的可靠性,促进水资源优化配置和用水结构的调整,实现水资源高效利用和科学管理,开展本次研究。【方法】采用比拟法成功预测了矿井涌水量,分析矿井涌水可利用量,开展项目用水水平分析。【结果】通过预测与分析得出,项目总用水量为797.85 m^(3)/d(29.12万m^(3)/a),矿井正常涌水量为886.5 m^(3)/d(36.94 m^(3)/h)。【结论】矿井涌水量可以满足用水需求,且水质达标,项目取用水是可靠的。

类比分析方法在矿井涌水量预测中的应用——以榆神三期矿区为例

榆神三期矿区位于防风固沙、水源涵养的重要生态功能区,地下水是维系区域生态系统的重要水源,准确估算矿井涌水量对区域地下水保护意义重大。我国现有矿井涌水量预测方法主要分为确定性(包括数值模拟法、解析法等)和非确定性(包括类比法、模糊数学模型、时间序列分析等)两大类。本研究采用类比法,分析了各拟类比矿井的水文地质条件、地质结构分区、煤层埋深、导水裂缝影响情况以及隔水层保留厚度等条件,在本矿区或临近区域内确定类比对象矿井,进一步分析了矿井各阶段开采规模、采煤方法、开采工作面等条件,明确了类比的开采阶段,得出了矿井涌水量预测结果,并对不同方法矿井涌水量预测结果进行了对比。合理采用类比法开展矿井涌水量预测,可为周边分布有敏感水环境保护目标的矿区,以及生态系统稳定性明显受地下水资源影响的矿区,科学制定地下水保护对策提供更为准确的数据支撑。

泡沫镍原位生长普鲁士蓝类似物构筑镍铁双金属氧化物催化剂的氧析出反应性能研究

开发高性能、低成本的氧析出反应(OER)催化剂对促进电解水制氢降低电耗、提高经济性具有重要意义。以导电泡沫镍为基底,采用冰水浴法原位生长镍铁普鲁士蓝类似物,氧化制备了镍铁双金属氧化物催化剂。分别采用X射线衍射、扫描电镜、高分辨率透射电镜和X射线光电子能谱方法对催化剂的物相组成、微观形貌和表面化学状态进行了表征,并采用电化学测试表征了催化剂的OER催化性能。结果表明,当氧化温度为200℃、氧化时间为2 h时,制备的催化剂中镍铁双金属氧化物高度分散在泡沫镍基底上,纳米颗粒最小,平均粒径为71 nm,可暴露的催化反应活性位点多,表现出最优的OER催化性能。该催化剂在1.0 mol/L的KOH电解液中,电流密度为10 mA/cm^(2)时,过电位仅为272 mV,并在电流密度为100 mA/cm^(2)时稳定运行了40 h,表现出优异的OER电化学稳定性。

沙坪煤业矿井充水因素分析及涌水量预测

通过调查水文地质条件和补充勘探,研究沙坪煤业充水因素并预测涌水量。结果显示:主要充水水源包括大气降水及地表水、第四系松散岩类孔隙水、奥陶系中统上马家沟组碳酸盐岩类岩溶裂隙水等;充水通道主要为断裂及破碎带、顶板采动破坏带和底板采动破坏带、废弃老窑和封闭不良钻孔等。采用富水系数比拟法预测全矿井正常涌水量约为126.7 m^(3)/h,最大涌水量约为242.6 m^(3)/h,为矿井水害防治提供了依据。