地面核磁共振技术在推求潜水含水层厚度及导水系数中的应用

根据21眼地质勘探孔、水文地质勘探孔及28个地面核磁共振（SNMR）勘探点资料,对比分析了钻孔揭露的含水层厚度与SNMR解译的含水层厚度、钻孔抽水试验所得含水层导水系数与SNMR解译的导水系数的差异,据此绘制出西辽河冲淤积平原潜水含水层厚度与导水系数分布图。结果表明,在SNMR试验噪音较小时SNMR解译的含水层厚度、导水系数与钻孔揭露的含水层厚度及水文地质试验结果吻合较好。利用SNMR技术解译含水层厚度、导水系数并通过少量钻孔及抽水试验予以校正,不仅可以节省大量勘探工作量,而且精度及可行度也较高。     

抽水蓄能机组调相压水系统设计与控制策略

鉴于调相压水系统是抽水蓄能机组抽水方向运行和调相工况运行的重要设备,且对抽水蓄能机组安全稳定运行和可靠工况转换起着非常重要的作用。从硬件配置上介绍了调相压水系统的构成和各设备的功能及选型原则,结合蓄能机组典型流程梳理了调相压水系统的控制逻辑,并结合现场实际测试结果验证了流程设计的合理性和科学性,对抽水蓄能电站调相压水系统的设备选型和控制策略研究具有一定的指导意义。     

柬埔寨磅士卑矿区水文地质参数计算及矿坑涌水量预测

以柬埔寨磅士卑矿区普查资料为依据,通过地表水文地质调查和抽水试验,查明矿床水文地质特征,利用Aquifertest软件计算含水层渗透系数K(0.00608 m/d),并采用大井法预测矿坑涌水量,为后续矿床开采及施工建设提供依据。     

天津地热对井回灌系统中的同位素示踪技术

为深入分析地热回灌开采中回灌水的运移规律、求证热储参数，本文选取二组中元古界雾迷山组地热对井，分别注入放射性同位素巧^35S（T12=87天）、^125I（T12=60天）进行示踪试验，并分别于第130天、51天检出峰值，以此数据计算出热储层的渗透系数、导水系数等有关参数，与传统的抽水试验算出的结果吻合良好。注入示踪剂在地层中的运移方向也与抽水试验观测到的结果完全一致，且形象直观，检出精度更高。同位素示踪技术能为进一步深入研究热储层在回灌前后压力场、温度场、水化学场的变化特征提供大量基本数据，也为天津乃至华北地区地热资源实施循环开发提供有效的技术保障。     

非稳定流非完整辐射井抽水试验水文地质参数的求解

针对辐射井抽水试验水文地质参数求解方法较少的问题,将仿Theis公式引入潜水非完整辐射井非稳定流抽水试验参数求解中,推导了潜水非完整井变流量非稳定流的井流公式,采用试算方法,通过VB编程,实现了计算水位过程与实测水位过程的对比,含水层参数求解取得了较理想的结果。结合新疆台兰河大型抽水试验,计算了均方根误差、平均误差、整群剩余系数和模型效率。结果表明,该方法计算所得水位过程与实测过程拟合效果理想,所得水文地质参数与Neuman法、前人研究结果吻合。     

裂隙岩体初始渗流场反演

初始渗流场的确定对于工程渗控设计具有重要的指导意义,而影响初始渗流场计算结果的主要因素为渗透系数和边界水头。因此,从提高初始渗流场计算结果的准确性出发,将裂隙产状和压水试验相结合来确定裂隙岩体渗透张量,并将粒子群算法应用到边界水头的反演中。工程实例表明,相比于传统的初始渗流场确定方法,采用所提方法计算所得测孔水位与实测水位误差更小,说明该方法有效可行。     

变速抽水蓄能发电电动机电磁设计与试验研究

根据变速抽水蓄能发电电动机的运行原理、等效电路以及功率传输特性,对10MW变速抽水蓄能发电电动机进行了电磁设计,确定了10MW变速抽水蓄能发电电动机的主要结构尺寸;建立了变速抽水蓄能发电电动机二维电磁场的数学方程和物理模型,对变速抽水蓄能发电电动机电磁场数学方程进行了计算,分析了变速抽水蓄能电机在发电机工况下亚同步速时磁力线和气隙磁密的分布情况,确定了在发电机工况下亚同步速时定子电压波形和定子电流波形,研究了定子铁芯损耗和转子铁芯损耗的分布规律;根据电磁设计参数加工制造了10MW变速抽水蓄能发电电动机样机,搭建试验测试平台,将试验测试结果和计算结果进行对比,验证了电磁设计方案的可行性和计算结果的准确性,为更大容量变速抽水蓄能电机的研究奠定了基础.     

基于电路等效法的抽水蓄能机组过水系统建模

针对抽水蓄能过水系统精细化建模问题,利用电路等效法推导了包含有压管道、调压室和水泵水轮机的抽水蓄能机组过水系统等效电路模型,然后运用多维基尔霍夫电压和电流定理,建立了整个过水系统电路拓扑结构的常微分矩阵方程,研究了基于电路等效法的抽水蓄能水机电联合仿真模型的仿真算法流程。针对洪屏抽水蓄能电站甩全负荷工况进行仿真,并对比电路等效法与特征线法得到的仿真结果。仿真试验结果表明,电路等效法准确、有效,相较于传统特征线法具有更好的稳定性和适应性。研究成果为抽水蓄能机组过水系统计算提供了新思路。     

甫弼矿区水文地质特征及矿坑涌水量预测

通过对矿区内地表水文地质调查、钻孔简易水文地质编录和分层抽水试验,查明了矿床水文地质特征及充水来源,并采用"大井法"预测矿坑涌水量。     

福建坑柄南井田水文孔抽水试验分析

对单孔稳定流抽水试验进行分析说明,并介绍计算水文地质参数和利用抽水试验资料建立曲线方程进行未来矿坑涌水量的方法.     

陕西省子长地区非饱和马兰黄土的渗透系数曲线研究

为研究陕西省子长地区非饱和马兰黄土的渗透特性,对其做了常规物理指标测定试验、X射线衍射试验、变水头渗透试验和土—水特征曲线试验,得到了非饱和黄土的各项物理性质参数、矿物成分及其百分含量、饱和渗透系数以及土—水特征曲线。根据测定数据,结合统计模型计算并绘制了非饱和黄土的K-θ曲线,得出非饱和黄土在脱湿过程中渗透系数在进气值前后随含水率的变化有明显差异。并引入土粒双电层模型,从微观角度解释了非饱和黄土渗透机理,为当地工程的设计施工提供了参考依据。     

伊犁一矿5号煤层底板砂岩含水层放水试验及参数计算

为了充分暴露5号煤层底板砂岩含水层的补给条件,查明含水层间的水力联系,计算相应的水文地质参数,从而系统地评价矿井开采水文地质条件,开展“大流量、大降深、长延时”群孔放水试验。利用Theis公式求取含水层水文地质参数,分析放水试验前后含水层的水质变化情况,判断含水层的补给条件。研究结果表明,5号煤层底板砂岩含水层渗透系数平均为0.647 m/d,该含水层透水性、联通性好,但其补给条件差,具有可疏降性,在放水试验区范围内与第四系及其他含水层之间水力联系差。     

Experimental Study on the Permeability and Thermal Resistance of the Cement Clinker Accumulation

A device was designed for measuring the permeability of cement clinker accumulation in three dimensions. In addition, the equivalent permeability and equivalent thermal resistance coefficient were introduced to evaluate the penetration ability in high temperature. First, the equivalent permeability of the accumulation in three dimensions was measured at a room temperature of 298 K and the order of magnitude was decided to be 10^?6. The difference degree of equivalent permeability was less than 15% in each direction; Then the rule of equivalent permeability in three‐dimensional changed with temperature was obtained by the air‐cooled experiments of the cement clinker accumulation at an initial temperature – 773 K; Finally, the law of equivalent thermal resistance coefficient was obtained through comparing the change of the permeability from high temperature to room temperature. The results showed that the equivalent thermal resistance coefficient change with temperature was nonlinear and the equivalent thermal resistance coefficient changed from 1.0 to 1.3 when the temperature was in the range of 298 K to 773 K.     

区间型单井承压水Dupuit求参公式

针对抽水试验确定水文地质参数存在不确定性的问题,从区间不确定性角度出发,基于非概率集合理论,推导出了单井承压水Dupuit求参公式的单变量和多变量区间解析表达式,即15个区间型单井承压水Dupuit求参公式,实现了从确定型求参公式到区间型求参公式的转变。通过对比蒙特卡洛法得到的实际区间上下限和推导出的公式计算的上下限,给出了这15个区间型求参公式计算结果相对误差的绝对值控制在10%以内时,相应变量的允许变化率,即各种情况下,允许变化率的最大值为1,最小值为0.1。实例应用结果表明,推导出的区间型求参公式可方便可靠地计算出渗透系数的区间响应,为地下水计算的不确定性研究提供了一种新途径。     

IV型瓶聚乙烯内胆材料氢渗透行为研究

对IV型高压储氢气瓶内胆材料高密度聚乙烯（HDPE）的氢气气体渗透性进行了研究,主要分析了结晶度及温度对HDPE氢渗透的影响。通过对试样熔融后降温过程的控制,制备了不同结晶度的HDPE试样,试验结果表明,随着结晶度的增加,试样的氢气气体渗透系数降低。当温度从15℃升高到80℃时,氢渗透系数升高了近一个数量级,但渗透系数的温度依赖性低于二氧化碳及甲烷。     

Computational modelling of unsaturated flow of liquid in heap leaching—using the results of column tests to calibrate the model

Unsaturated flow of liquid in a bed of uniform and spherical ore particles is studied numerically and experimentally. An unsteady and two-dimensional model is developed based on the mass conservation equations of liquid phase in the bed and in the particles. The model equations are solved using a fully implicit finite difference method giving the distribution of the degree of saturation in the particles and in the bed and the vertical velocity of flow in the bed, as well as, the effect of periodic infiltration on the above distributions. To calibrate the computational model, several column tests are performed using periodic infiltration of water on 40 cm high columns composed of ore having particles smaller than 25 mm. The numerical analysis shows that (a) the results obtained from numerical modelling under the same operating conditions as used for column tests, are in good agreement with those from experimental procedure, (b) the degree of saturation of the bed and the time required to reach steady state conditions depend on the inflow of water and intrinsic permeability of the bed and (c) the velocity fluctuations and the fluctuations of the degree of saturation in the bed depend on the inflow of water, period of infiltration, height and intrinsic permeability of the bed.     

泵抽式电缆地层测试复合流形模型研究及应用

泵抽式电缆地层测试是在油气资源评价中快速获得储层的渗透率的技术手段。目前对泵抽式电缆地层测试压力资料分析多采用球形流分析法,而对于大排量泵抽式电缆地层测试器,在薄储层和储层的上下边界,测试流动形态则会从球形流过渡为柱形流,如果仍然采用球形流动解释方法,就会给解释结果带来较大的误差。通过分析泵抽式电缆地层测试储层流动形态,并应用油气层渗流力学理论,推导出了在球形流与柱形流复合流动形态下的渗透率求解模型。选择某油田一口井的电缆地层测试资料为例对该模型进行验证。由于测试目的层为层薄,渗流为球形流与柱形流复合流动形态,采用模型计算得到储层渗透率为46.6×10-3μm2,与该层段取心分析岩心渗透率(56×10-3μm2)接近,证明该渗透率求解模型可行。     

不透水地基均质土堤防渗墙渗透系数五段算法

针对堤坝工程施工中防渗墙渗透性检验方法的不足,基于不透水地基均质土堤渗流计算三段法,提出了防渗墙渗透系数计算五段法,并通过注水试验数值模拟验证该算法。结果表明,当土体和防渗墙渗透性相差200~1 000倍时该方法检验结果较准确;当土体和防渗墙渗透性相差小于200倍时,可增加下游观测孔数量,消除误差;当土体和防渗墙渗透性相差大于1 000倍时,计算误差无法消除,但计算结果可在定性分析时使用。因此,通过设定一定条件,该方法可应用于实际工程。     

Experimental Assessment of the Thermo-Hydraulic Performance of Automobile Radiator with Metallic and Nonmetallic Nanofluids

Abstract

The overall heat transfer of a cross flow heat exchanger can be enhanced by using the nanofluids as coolant, which finds application in reducing the size and weight of automobile radiator. However, improving the heat transfer using nanofluids can be accompanied by simultaneous variations in the required pumping power. This study experimentally evaluates the thermo-hydraulic performance of three nanofluids—metallic (copper, aluminum) and nonmetallic (multiwalled carbon nanotube (MWCNT))—as coolant for an automobile radiator by utilizing an in-house test rig. An enhancement in overall heat transfer coefficient can be observed with nanocoolants (nanofluid as coolant), compared to the de-ionized water at the same Reynolds number. The maximum enhancement in the overall heat transfer coefficient was observed to be 40, 29, and 25% for MWCNT, copper, and aluminum nanofluids, respectively. The thermal performance of coolants was also compared with the same pumping power criterion. The overall heat transfer coefficient of nanofluids were higher than basefluid at low pumping power range and the trend changes with increase in the pumping power. The present study shows that the heat transfer characteristics at the same Reynolds number as well as at the same pumping power needs to be considered for the selection of appropriate nanocoolant for automobile radiator application.