枯竭油藏型储气库库容量化室内实验研究

在油藏改建地下储气库时,为了研究不同初始含水饱和度对库容的影响,利用实际矿场岩心开展了不同初始含水饱和度条件下气驱油水多轮次注采实验,分析了不同初始含水饱和度下气驱油水后的驱替效率及建库效果。结果表明,低含水饱和度条件下,油相的相对渗透率显著高于水相而更易被驱替出,因此主要通过气驱油来提高储气空间;中、高含水饱和度时,水相更易被驱替出,储气空间的提高逐渐由被驱替出的原油体积贡献转向于由驱替出的水相体积贡献。相同注采轮次下,由于储层岩石水湿及渗吸作用,高初始含水饱和度时的剩余水饱和度增大,气驱油水总的驱替效率降低,储气库的注采能力和库容相对减小;储层初始含水饱和度增大会降低气驱油水的驱替效率,不利于提高原油采收率及储气库扩容;初始含水饱和度越高,储气库达容时间越久,建库初期的注采能力越低。该研究成果可为油藏型储气库注采能力评价和库容分析提供指导。

基于本源性问题的高中物理电学实验二轮复习

结合教学实践,回归本源性问题的高中物理二轮电学实验复习,从探寻学生本源性问题的来源和利用本源性问题培养学生的学科核心素养两方面入手,让学生学会用解决问题的方式解题,构建更具有针对性和高效性的二轮复习课堂教学。

渗镍高速工具钢／砂带基材的摩擦磨损实验研究

为探究共轭接触轮/砂带基材之间的磨损失效机理,有效减缓共轭轮的磨损程度,在自行设计的砂带摩擦磨损实验台架上,进行了渗镍高速工具钢与砂带基材的配对磨擦磨损实验。通过分阶段观测渗镍高速工具钢实验轮表面粗糙度和表面形貌,揭示出粘着磨损机理占主导,疲劳磨损和氧化磨损机理其次,磨粒磨损机理比重最小;其次通过分阶段测定实验轮质量、几何尺寸等参数变化规律,计算出其磨损率比渗镍前至少下降约57%。研究表明:表面渗镍能有效提高普通高速工具钢共轭接触轮材料的耐磨性,从而能够提高共轭砂带磨床的磨削效率和加工精度。

机车车辆耦合动力学特性及实验研究

有关机车轮轨系统的动力学建模中少有考虑轴箱轴承非线性载荷以及机车车辆空间耦合关系.基于轴箱轴承的时变非线性接触载荷,建立了机车轮对的空间耦合动力学模型,为验证该理论模型的正确性,搭建了机车轮对测试实验.实验结果表明:轴箱轴承振动在空间具有非线性强耦合关系,箱轴向激励引起的垂向振动幅值为0.216mm,约为轴向振动幅值的22.2%.机车轮对空间耦合动力学理论模型能准确反映机车在轨道不平顺激励下的振动特性,为轴箱轴承等关键部件的设计提供了理论支撑.

轮对反压试验及退轮设备研制

本文主要针对大型养路机械设备轮对反压实验及退轮进行研究,并对如何通过制作工装确保完液压式轮对压装机实现轮对反压及退轮操作进行了介绍。

Experimental analysis of the slip sinkage effect based on real vehicle test

To improve the semi-empirical model, the slip sinkage effect is analyzed based on the real vehicle test. A dynamic testing system is used to gain the dynamic responses of wheel-soil interactions, The Gauss-Newton algorithm is adopted to estimate the undetermined parameters involved in the slip sinkage models. Wong＇s original model is compared with three typical slip sinkage models on the prediction performance of a drawbar pull. The maximum error rate, root mean squared error and correlation coefficient are utilized to evaluate the performance. The results indicate that the slip sinkage models outperform Wong＇s model and greatly improve the prediction accuracy. Lyasko＇s model is confirmed as an outstanding one for its comprehensive performance. Hence, the existence of the slip sinkage effect is validated. Lyasko＇s model is selected as an optimal one for the practical evaluation of military vehicle trafficability.

水泥灌浆半柔性路面混合料抗车辙性能研究

在大空隙(20%～30%)母体沥青混合料中灌入水泥砂浆,形成一种水泥-沥青复合半柔性路面材料。对其抗车辙性能和疲劳特性进行室内试验研究,结果表明,此路面材料具有良好的高温稳定性,在试验温度为70℃、轮胎接地压强为1.0 MPa非常规车辙试验条件下,其动稳定度均在6 000以上,与常规沥青混合料相比较,其更能适应高温和重载作用下的路面抗变形需要;温度对半柔性路面材料的抗裂性能有明显影响,断裂强度随着温度降低而增大。

Research on hydraulic wind turbine semi-physical simulation platform

According to a research on the 30kVA simulation experimental platform of hydraulic wind tur- bine, its basic structure, composition and operation principle are expounded in this paper. An in- verter motor is used to simulate the wind turbine, while a similarity calculation method is applied be- tween the small and large wind turbine. A fixed displacement pump-variable motor closed loop is used as the main transmission system, and a self-excited synchronous generator generates electricity through the grid connection. The experiment and simulation study on the speed and power control of the hydraulic wind turbine is conducted, based on the experimental platform, thus correctness and progressiveness of the experiment platform is further verified. The experimental platform study lays a foundation for further research on the characteristics of hydraulic wind turhln~

Experimental Study on the Interspecific Interactions Between the Two Bloom-Forming Algal Species and the Rotifer Brachionus plicatilis

The interspecific interactions between the rotifer Brachionus plicatilis and two harmful algal blooms(HAB) species were investigated experimentally by single culture method. B. plicatilis population and the growth of the two algae were compared at different algal cell densities. The results demonstrated that the B. plicatilis obtained sufficient nutrition from Prorocentrum donghaiense to support net population increase. With exposure to 2.5×104 cells mL-1 of P. donghaiense,the number of B. plicatilis increased faster than it did when exposed to other four algal densities(5,10,15 and 20 ×104 cells mL-1),and the increase rate of B. plicatilis population(r) at this algal density was 0.104 ± 0.015 r d-1. Cell densities of P. donghaiense decreased due to the grazing of B. plicatilis. In contrast,Heterosigma akashiwo had an adverse effect on B. plicatilis population and its growth was largely unaffected by rotifer grazing. In this case,B. plicatilis population decreased and H. akashiwo grew at a rate similar to that of the control.

Experimental study by online measurement of the precipitation of nickel hydroxide: Effects of operating conditions

The objective of this work is using the online measurement method to study the process of precipitation of nickel hydroxide in a single-feed semi-batch stirred reactor with an internal diameter ofD = 240mm. The effects of impeller speed, impeller type, impeller diameter and feed location on the mean particle size d43 and particle size distribution （PSD） were investigated, d43 and PSD were measured online using a Malvern Insitec Liquid Pro- cess Sizer every 20 s. It was found that d43 varied between 13 kwh and 26 lain under different operating conditions, and it decreased with increasing impeller diameter. When feeding at the off-bottom distance of D/2 under lower impeller speeds, d43 was significantly smaller than that at D/3. PSDs were slightly influenced by operating conditions.

Experimental Fault Detection in Rotation System Using State Observers by LMIs

Rotating systems have many applications in wide-ranging industrial contexts. The breakdown of this equipment results in economic wastes and leads to dangerous situations. To avoid such problems is very important, and it can be done through tools that inform about the existence of faults, as well as, about their progress in time. A review of the modeling process used for rotor-support-structure shows that the finite element method is the maj or method employed. In this paper, with the aid of well defined theoretical models, obtained using the finite element technique, and the state observer method for the identification and location of faults, it is possible to monitor the parameters of a rotor-support-structure system, including the foundation effects. In order to improve safety, these parameters must be supervised in case of the occurrence of failures or faults. The state observers are designed using Linear Matrix Inequalities （LMIs）. Finally, experimental results （using for this a rotation system in the mechanical vibrations laboratory at Ilha Solteira＇s Mechanical Engineering Department） demonstrate the effectiveness of the methodology developed.

第五轮实验室崭新策划，手把手教你黑客技术

追求技术的提高是黑客们永恒的话题，无数人在为这一梦想而挥洒自己的精力，奉献自己的热情，但更多的朋友却苦于黑客技术入门太难，在“黑客”这个神秘的圈子外徘徊很久都不能融入他们，痛苦之情溢于言表。黑防攻防实验室已经圆满地开展四轮了，第五轮也正在紧张的准备之中，而这一次，我们将给广大的菜鸟朋友们准备一份厚礼！

基于深度学习理念的二轮物理实验复习教学

从高考物理实验考查的新旧方案对比中发现,物理实验考查的不确定性增加,这就要求物理实验的复习既要注重基础,又要关注联系,还要凸显创新。在二轮复习中,运用深度学习的理论构建以基础实验为核心、实验内容有机整合的教学,进而提升学生的物理实验能力。

Ultimate Strength Assessment of a Tanker Hull Based on Experimentally Developed Master Curves

A geometrically similar scaling was made from small-scale specimen to full-scale stiffened panels and then their collapse behaviour is investigated. It is considered that the stiffened panel compressive ultimate strength test was designed according to geometrical scaling laws so that the output of the test could be used as representative of the stiffened panels of the compressive zone of a tanker hull subjected to vertical bending moment. The ultimate strength of a tanker hull is analysed by a FE analysis using the experimentally developed master stress-strain curves which are obtained by the beam tension test and the compressive test of the stiffened panel, and are then compared with the result achieved by the progressive collapse method.

ERT Imaging of Gas-Liquid Mixing in Agitated Vessel

An investigation using Electrical Resistance Tomography （ERT） was carried out in order to characterize gas-liquid mixing in an agitated vessel. The experimental work was carried out in a 400 mm diameter agitated vessel that was fitted with four planes, 16 stainless steel electrodes. Agitation was carried out using the Lightnin Labmaster and Rushton turbine while conductivity data acquisition was carried out using the ITS P2000 ERT system. A Mathlab code was developed to construct a surface plot for gas hold-up from the ERT data. Various gas dispersion conditions such as flooded, loaded and fully dispersed were successfully characterized using the ERT technique.

Experimental Tests of the Operating Conditions of a Micro Gas Turbine Device

The aim of this work is to analyze the performance of a commercial micro gas turbine, focusing on the analysis of the fuel consumption and the outlet compressor and turbine temperature at various rpm, and to evaluate and compare the efficiency of the device. A test bench has been assembled with the available equipment in the laboratory of the department of mechanical and aerospace engineering in Roma. By using the software supplied by the manufacturer, the evaluation of the operating performance of the device at different speeds has been performed, obtaining all the values of interest.

Experimental Investigation of Reynolds Number Effect on Wind Turbine Profiles in the Cryogenic Wind Tunnel Cologne DNW-KKK

Wind turbine size has increased continuously and correspondingly also its Reynolds numbers. The Reynolds number effect can therefore no longer be ignored in design and optimization of wind turbines. Reliable profile test data should be available. A suitable facility for testing wind turbine profiles at high Reynolds numbers is the Cryogenic Wind Tunnel Cologne DNW-KKK. By means of injecting liquid nitrogen the tunnel can be cooled down to 100 K and the Reynolds number therefore can be raised accordingly. The maximum Reynolds number for 2D profile tests can reach 27x10^6. In this paper the test uncertainty and the flow quality of DNW-KKK were analyzed. Then some test results on the Reynolds number effect of the wind turbine profiles will be presented. The Reynolds number effect is different from model to model. Especially for thick profiles and flow control devices the Reynolds number effect is not always like the description in literature.

A Practical Hull Form Design of Ferry Using Hybrid Scheme Method and Performing Experiment

Prediction of ship performance in preliminary ship design is an important consideration. It could guarantee ship in safe and comfort. However, many design works did not involve simultaneously ship performances predictions in preliminary design. Moreover, ship designers sometimes modified a ship form to obtain proper design without ship performance consideration. Therefore, this study concerns on predictions of total resistance and added wave resistance of a ferry using a hybrid particle-grid method and then its motions response after modifying bow and stern parts by conducting experiment. Research results show total resistance and added wave resistance have a significant different, therefore, it would be an important consideration in determining ship powering in preliminary ship design. The non-dimensional added wave resistance increases in increasing wave length from λ/Lpp = 0.5 to 1.0 and it decreases after L/λ = 1.0. In addition, it tends to decrease caused by increasing ship speed. The comparison of averaged heave and pitch amplitudes between basic forms after modifying bow and stem parts is quiet similar. However, the rolling amplitude of the modified form is significantly higher comparing with the basic form. We conclude that a ship could be design in preliminary design take into account performances predictions by using numerical method and experimental work.

Tree Rings Tell Moisture Variability on Tibetan Plateau

Tibetan Plateau（TP）is known as＂Asia’s Water Tower＂,but it remains an interesting question whether the water supply to the north of the plateau is the same with that to the south.Dr.ZHANG Qibin and coworkers from the State Key Laboratory of Vegetation and Environmental Change.CAS Institute of Botany recently tried to answer it from their studies of tree rings.They found evidences for different moisture conditions on the north and south of the plateau during the past five and a half centuries,and particularly,

Building Effects on a Horizontal-Axis Micro Wind Turbine： Experimental and Fluid-Dynamic Analysis

In this work, the efficiency ofa 1 kWp horizontal-axis wind turbine which is installed on the roof of the engineering building at the University of Salento has been evaluated, by means of CFD （computational fluid dynamic） and experimental data. Particularly, the influence of the building on the micro wind turbine performance has been studied and the numerical results （wind velocity fields and turbulence intensity above the building） have been compared with the experimental data collected over a period of three years. The results have shown that horizontal-axis wind turbines suffer from wake effect due to buildings, therefore, best sites in urban area have to be identified by a careful fluid dynamic analysis aimed at evaluating all causes that can reduce significantly the performance of the generator： in fact, building should allow to exploit increased wind intensity, but often this advantage is voided by turbulence phenomena, as in the case under investigation where the measured aerogenerator efficiency is lower than the nominal performance curve. Then, the best site can be found by crossing the contours of wind velocity with the turbulence intensity fields： in this way it is possible to localize an area （best location） where the aerogenerator can give maximum performance.