超压非牛顿流体弹性水力压裂的几何形状
Geometry of elastic hydrofracturing by injection of an over pressured non-Newtonian Fluid
摘要：
对弹性各向同性介质中注入超压流体压裂裂缝的成核和扩展进行了实验研究。将非牛顿流体注入明胶中，假设明胶的力学性质在实验应变率下是各向同性的。线弹性理论预测，与明胶粘合断裂相关的塑性形变限于扩展裂缝尖端前方的一个小区域，并且当流体压力超过裂缝壁的法向应力时，扩展将保持（Chávez-Álvarez，2008）（即，最小压缩应力），导致单一模式I断裂几何形状。然而，我们观察到II型和III型裂缝的传播以及二次裂缝的成核，相对于初始裂缝具有倾斜至垂直的轨迹。在视频（http：//hdl.net.net/1813/14122）中，实验证据表明，断裂形状取决于明胶的粘弹性以及断裂扩展所实现的应变速率。
英文摘要：
The nucleation and propagation of hydrofractures by injection of over pressured fluids in an elastic and isotropic medium are studied experimentally. Non-Newtonian fluids are injected inside a gelatine whose mechanical properties are assumed isotropic at the experimental strain rates. Linear elastic theory predicts that plastic deformation associated to breakage of gelatin bonds is limited to a small zone ahead of the tip of the propagating fracture and that propagation will be maintained while the fluid pressure exceeds the normal stress to the fracture walls (Chávez-Álvarez,2008) (i.e., the minimum compressive stress), resulting in a single mode I fracture geometry. However, we observed the propagation of fractures type II and III as well as nucleation of secondary fractures, with oblique to perpendicular trajectories with respect to the initial fracture. In the Video (http://hdl.handle.net/1813/14122) experimental evidence shows that the fracture shape depends on the viscoelastic properties of gelatine coupled with the strain rate achieved by fracture propagation.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
