• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Spatial Variability in Seepage from Unlined, Open Channels.
【24h】

Spatial Variability in Seepage from Unlined, Open Channels.

机译：无衬砌开放渠道渗流的空间变异性。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Recent research into the interactions between streams or lakes and the aquifers beneath them highlights the usefulness of methods for determining movement of water between surface and groundwater sources. Several methods have successfully been employed to estimate these interactions in a variety of environments. As temperature sensor technology and computer capability has improved in the past decades, an increasing number of studies have used temperature and pressure information collected in surface water, streambed porous media, and groundwater in one-dimensional analytical or one-, two-, or even three-dimensional (1D, 2D, or 3D) numerical models that combine heat transport and fluid flux equations. This work compared the advantages and limitations of one- vs. two-dimensional numerical models and the applicability of the Stallman analytical solution for use in applications of heat as a tracer. Although the use of temperature data for estimating seepage and hydraulic conductivity has been shown to have several advantages over many other methods, it shares a common disadvantage of being a point measurement. Because spatial variability in seepage is often an important factor, a new model using the diffusion analogy to the shallow-water (Saint-Venant) equations was developed as a step toward estimating seepage losses from unlined channels.;Comparison of numerical models showed that a 1D model can be useful when a simple, comparatively low-cost estimate of seepage from streambed temperature data is desired and streambed heterogeneity is not a concern. However, the assumption of strictly vertical water movement inherent in 1D models highlights the importance of temperature sensor placement to satisfy this condition. Alternatively, the Stallman analytical solution precisely reproduced velocities for moderate rates of infiltration (approximately ∼1.5--4 m d -1) despite sensor noise and uncertainty in either sensor spacing or thermal diffusivity. When seepage was close to zero or flow was from the groundwater into the streambed, uncertainty in input parameters and noise due to sensor accuracy had an effect on the accuracy of predicted seepage rates, likely due to a reduced change in amplitude with depth.;The diffusion-wave model, coupled to the U.S. Geological survey groundwater model MODFLOW, produced longitudinal seepage velocities for several reaches of two irrigation canals that were comparable to the estimates reported in previous studies. This model may be a useful tool for predicting surface water/groundwater interactions along comparatively long stretches of man-made or natural channels at a finer scale than was previously convenient.
机译：对溪流或湖泊及其下方的含水层之间相互作用的最新研究突显了确定水在地表水源与地下水源之间运动的方法的实用性。已经成功采用了几种方法来估计各种环境中的这些相互作用。在过去的几十年中，随着温度传感器技术和计算机功能的提高，越来越多的研究使用了在一维分析或一维，二维甚至是一维分析中收集的地表水，流化多孔介质和地下水中的温度和压力信息。结合热传递和流体通量方程的三维（1D，2D或3D）数值模型。这项工作比较了一维和二维数值模型的优点和局限性，以及Stallman分析解决方案在将热量用作示踪剂时的适用性。尽管已经证明，使用温度数据来估计渗透率和水力传导率比许多其他方法具有多个优点，但是它也具有点测量的共同缺点。由于渗流的空间变异性通常是一个重要因素，因此开发了一种使用扩散模拟法（类似于浅水（Saint-Venant）方程）的新模型，作为估算单线渠道渗流损失的一步。数值模型的比较表明，当需要根据流化床温度数据进行简单，相对低成本的渗流估算，而无需考虑流化床的非均质性时，一维模型将非常有用。但是，一维模型中固有的严格垂直水运动的假设凸显了满足此条件的温度传感器放置的重要性。另外，尽管传感器噪声和传感器间距或热扩散率的不确定性，Stallman分析解决方案仍可以精确地再现中等渗透速度的速度（约1.5--4 m d -1）。当渗流接近零或从地下水流入河床时，由于传感器精度导致的输入参数不确定性和噪声对预测渗流率的精度有影响，这可能是由于幅度随深度的减小而减小的缘故。扩散波模型，再加上美国地质调查局地下水模型MODFLOW，在两个灌溉渠的多个河段产生了纵向渗流速度，这与以前的研究报道的估计值相当。该模型可能是有用的工具，用于以比以前方便的更精细的比例来预测沿着相对较长的人造或自然通道延伸所产生的地表水/地下水相互作用。

著录项

  • 作者

    Shanafield, Margaret A.;

  • 作者单位

    University of Nevada, Reno.;

  • 授予单位 University of Nevada, Reno.;
  • 学科 Hydrology.
  • 学位 Ph.D.
  • 年度 2010
  • 页码 110 p.
  • 总页数 110
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号