埋藏型岩溶地下水源地的三维数值模拟——以天津市宁河北岩溶地下水源地为例

根据宁河北岩溶地下水源地已有的水文地质勘查成果和大型抽水试验资料,对研究区水文地质条件进行概化,建立地下水流三维非稳定流数学模型并进行数值计算,对开采性抽水试验的地下水位变化过程进行模拟。结果表明,该模型可以刻画埋藏型水源地地下水流场的变化过程,用它对规划的水源地三种开采方案的开采动态进行预测计算也取得了良好的效果。模拟计算中将开采条件下浅层第四系含水层对深层奥陶系灰岩含水层的越流补给处理为边界条件,可以刻画埋藏型水源地在开采条件下获得的补给增量。      

Application of wellhead suction anchor technology in the second production test of natural gas hydrates in the South China Sea

Traditional suction anchor technology is mainly used in the fields of subsea structure bearing foundations, single-point mooring systems and offshore wind power. It is characterized by providing sufficient lateral and vertical bearing capacities and lateral bending moment. The anchor structure of a traditional suction anchor structure is improved with wellhead suction anchor technology, where a central pipe is added as a channel for drilling and completion operations. To solve the technical problems of a low wellhead bearing capacity, shallow built-up depth, and limited application of conductor jetting in the second production test of natural gas hydrates (NGHs) in the South China Sea (SCS), the China Geological Survey (CGS) took the lead in independently designing and manufacturing a wellhead suction anchor, which fulfilled the requirements of the production test. This novel anchor was successfully implemented in the second production test for the first time, providing a stable wellhead foundation for the success of the second production test of NGHs in the SCS.©2022 China Geology Editorial Office.     

Computationally efficient stochastic optimization using multiple realizations

The presented study is concerned with computationally efficient methods for solving stochastic optimization problems involving multiple equally probable realizations of uncertain parameters. A new and straightforward technique is introduced that is based on dynamically ordering the stack of realizations during the search procedure. The rationale is that a small number of critical realizations govern the output of a reliability-based objective function. By utilizing a problem, which is typical to designing a water supply well field, several variants of this “stack ordering” approach are tested. The results are statistically assessed, in terms of optimality and nominal reliability. This study demonstrates that the simple ordering of a given number of 500 realizations while applying an evolutionary search algorithm can save about half of the model runs without compromising the optimization procedure. More advanced variants of stack ordering can, if properly configured, save up to more than 97% of the computational effort that would be required if the entire number of realizations were considered. The findings herein are promising for similar problems of water management and reliability-based design in general, and particularly for non-convex problems that require heuristic search techniques.     

地质科技园水源热泵中央空调回灌系统气堵防治技术研究

近年来水源热泵空调系统的应用越来越广泛,回灌技术是水源热泵系统的发展的瓶颈,研究分析水源热泵回灌能力、回灌状况等,解决回灌过程中普遍出现的回灌难问题,能够为水源热泵系统开发利用提供有力的技术支撑。通过对地质科技园办公楼水源热泵中央空调实地调研,了解目前回灌系统的回灌量变化状况。结合空调系统以往运行中的经验,研究分析回灌系统回灌效果较差的原因是气堵原因。为方便实时掌握空调运行系统的运行情况,设计安装了水源热泵空调工程长期运行监测系统。围绕解决回灌系统出现的气堵问题,研发安装了新型回灌井头系统,提升系统回灌能力。     

聊古1井井口装置改造及其观测效果分析

介绍了自流热水井断流情况下, 调整观测技术思路, 并通过井口装置改造, 实现人工连续自流条件下的地下流体综合观测。 改造后一年多的观测实践表明, 多数测项仍可继续观测, 观测产出的动态特征与断流前天然自流状态下的动态特征基本一致。