论文部分内容阅读
伴随着现代信息技术的发展,现代力学的研究进入了一个新的阶段.本文将钱学森先生介绍的现代力学概念赋予了新的内涵,概括了现代力学的研究主体、研究方法和主要研究方向.从拉格朗日方程出发,按照表征元的物理变量和积分区域的几何表述,对计算力学的基本方法进行了分类,提出了通过实验和数值模拟共同获得介质的力学参数、研究介质力学特性和行为的思路和方法,在此基础上建立了表征元(计算单元)的积分——微分方程,体现了现代力学基本理论框架的特点.表征元的材料特性、力学行为以及由表征元构成的宏观介质全场运动规律均是现代力学的重要研究内容.现有材料实验目的是获得抽象为连续介质的材料应力应变关系和材料强度,而现代力学可以突破这个限制,通过多变量测量并结合数值模拟获得材料的特征和演化规律.在现代力学中全场解可以由数值计算获得,并由监测结果校核.通过与丰富的监测结果比较,数值模拟不可信的问题会逐步化解.页岩气开发的关键问题是研究地下页岩在各种条件下的破裂演化规律.页岩气开发新方案的技术路线应该是现代力学先行,以避免盲目在工程尺度上进行方案论证;借助现代力学可以打破水力压裂技术的局限性,探索新的技术方案.主要理论研究包括以下几个方面:(1)在认识表征元破裂度、渗透性演化的基础上,寻求关联性的理论表述方法;(2)研究体破裂度的渗流场、破裂场以及颗粒的相互作用规律;(3)时空全尺度模拟需要从理论上研究新的力学模型,其中包括借用岩体表征元破裂度和灾变破裂度的概念,实现破裂场与材料渗透性关联;(4)由流量、井口压力曲线计算出的岩体破裂参量可以被页岩气的产量校核,从而为提出新的工程方案、指导工程施工提供可参考的技术指标.
With the development of modern information technology, the research of modern mechanics has entered a new stage.This paper gives new connotation to modern mechanics introduced by Mr. Qian Xuesen, summarizes the main body, research methods and main research directions of modern mechanics. Based on the Lagrange equation, the basic methods of computational mechanics are classified according to the physical variables of the characterization unit and the geometric expressions of the integral area. The mechanical parameters of the medium are obtained through experiments and numerical simulations, and the mechanical properties and behaviors of the medium are studied. , This paper builds the integral-differential equation of the characterization unit (calculation unit), which embodies the characteristics of the basic theoretical framework of modern mechanics.The material properties, mechanical behavior of the characterization unit and the macroscopic medium composed of the characterization unit The motion of the whole field is an important research content of modern mechanics.The purpose of the existing material experiment is to obtain the stress-strain relationship and the material strength of the material which is abstracted as a continuous medium, and modern mechanics can break through this limitation and obtain by multivariate measurement combined with numerical simulation Material characteristics and evolution of the law in the modern mechanics audience can Calculated from the results of the monitoring and verified by the monitoring results.The numerical simulations of the untrustworthy problems will be gradually solved by comparison with the abundant monitoring results.The key problem in the development of shale gas is to study the rupture evolution of underground shale under various conditions The rule of law.Shale gas development of new programs of the technical route should be the first in modern mechanics, in order to avoid blindly in the project scale program demonstration; with modern mechanics can break the limitations of hydraulic fracturing and explore new technical solutions.Main theoretical studies Including the following aspects: (1) Seeking the theoretical formulation of the correlation based on the understanding of the rupture and permeability evolution of the characterization unit; (2) Studying the seepage field, the rupture field and the law of particle interaction ; (3) Full-scale spatio-temporal simulation requires a theoretical study of new mechanical models, including the concept of using rock mass to characterize elemental rupture and catastrophic rupture, to correlate the fracture field with material permeability; (4) The rock mass rupture parameters calculated by the pressure curve can be checked by the production of shale gas so as to provide a reference technology for proposing new engineering schemes and guiding construction projects Mark.