Articles techniques et présentations

The use of high-resolution topography in the finite element model demonstrates that deformation from a shallow pressure source can be dramatically affected by overlying relief, not only in magnitude, but also in azimuth. This result is significant as it allows traditionally anomalous ... En savoir plus

Volcanic eruptions are often preceded by periods of unrest, where the behavior of the volcano deviates from a background level towards one of increasing concern [1]. Understanding what causes and contributes to unrest is a key challenge in volcanology today, influencing risk mitigation ... En savoir plus

Groundwater-bearing geological layers respond to and modify the surface expressions of magmatic activity, and they can also become agents of volcanic unrest themselves. Interpretations of unrest signals as groundwater responses to changes in the magmatic system can be found for many ... En savoir plus

In the medium term, gas hydrate reservoirs in the subsea sediment are intended as deposits for carbon dioxide (CO2) from fossil fuel consumption. This idea is supported by the fact, that CO2 hydrates are more stable than methane hydrates at certain conditions. The potential of producing ... En savoir plus

The Atlantis massif is a domal submarine seamount close to the mid-Atlantic Ridge at 30 °N. Close to the crest of the Massif, the Lost City hydrothermal field (LCHF) has been active for at least 120,000 years, venting fluids with a temperature of 40-90 °C. 5 km north of Lost City, a ... En savoir plus

Finite element (FE) modelling of ultrasonic propagation using COMSOL Multiphysics® simulations can be used to create images of waves. Unfortunately, in time-stepping solutions, it is possible for numerical instabilities to grow large and dominate the solution adversely. Any design of ... En savoir plus

互层岩体台阶爆破中力学差异性较大的岩层影响了炸药能量的均匀分布,为了快速确定影响爆破效果的主控岩层的位置及台阶整体炸药单耗,采用数值分析的方式探讨了主控岩层对炸药能量分布特征的影响规律,实验结果表明:采用连续装药结构时力学差异性较大的夹层处质点运动速度更为集中,而间隔装药可改善台阶内速度场的分布均匀程度;由最小抵抗线原理分析发现主控岩层的厚度和力学性质是影响炸药能量传递方向的主要因素;在此基础上结合波阻抗原理,构建了考虑台阶岩体整体力学特性及各岩层局部工程特征的能耗分级体系,通过现场测试取得了良好的应用效果,验证了该方法的可行性 ... En savoir plus

井下牵引机器人是一种安装在测井、射孔或修井工具串前端的自驱动装置，其核心作用是解决传统电缆或钻杆输送方式的局限性。其工作环境极端，给设计与可靠性评估带来了巨大挑战。传统的经验设计和单场分析方法难以准确预测其在实际井筒中的结构特性与牵引性能。本研究基于COMSOL Multiphysics多物理场仿真平台，对一款电动轮式牵引机器人进行了全流程的建模仿真与性能预测，建立了牵引机器人的几何模型，并系统性地研究了其核心物理过程。牵引机器人在运动过程中，伸缩臂可根据井筒尺寸自适应调节角度。将模型简化为二维结构，可以更直观地观察伸缩臂角度自适应调节的过程。在水平井 ... En savoir plus

页岩储层水力压裂中的裂缝扩展行为直接影响裂缝网络形态与油气产能提升。本文基于 COMSOL Multiphysics 建立三维流固耦合压裂数值模型，模拟并分析了五类典型压裂情形：单一裂缝扩展、两簇裂缝扩展及互相干扰、三簇对称压裂、三簇完全压裂以及水平主裂缝与垂向天然裂缝相交的情形。本文首先介绍了耦合力学与孔隙流体动力学控制方程、材料与边界条件，然后引入室内实体实验参数作为模型校核（包括页岩破裂韧性、抗拉强度、弹性模量与渗透率等特性）。在 COMSOL 中采用损伤参数化的线弹性-弹塑性破裂捕捉策略，并结合能量释放率与临界应力强度因子判据来判定裂缝的起裂与扩展。数值结果显示 ... En savoir plus

This study focuses on the design and optimization of a logging while drilling (LWD) tool with look-ahead detection capabilities, which is widely used in measuring formation resistivity and detecting formation boundaries ahead of the drill bit during oil and gas drilling operations. The ... En savoir plus