潜孔锤多柔体系统接触冲击的理论与建模

Because of the complexity of the transient contact process, the contact/impact of the DTH hammer drilling system is the "bottleneck" problem of the flexible multi-body dynamics in the current study..The project will adopt the discrete techniques of modal analysis and modal truncation in order to settle down the modeling theory of the plane contact/impact in the DTH hammer system, aiming to impacting process of this flexible piston-bit-rock multi-body system..The project will initially build up the governing equation of the two flexible plane impacting rods, end of which is supported by a spring. General solution of the partial differential equation will be solved by means of separation of variables. The regular effect of system parameters, boundary and initial conditions on flexible piston-bit-rock will be researched with mathematical mechanics method. The study intends to build the theoretical model of two flexible plane contact/impact rods, which is unique and distinguished from the previous one..The project will uses the elastic-plastic shear strength theory to build the theory of the Hertz impact critical velocity according to the characteristics of Hertz contact yield region, For lumped parameter modeling with Hertz contact. The process of the modeling focuses on high efficiency and practicality. .The systematic research will be both rich in the general solutions of the two flexible contact/impact rods with end of supporting spring, and establish a system of modeling methods and theory on the flexible contact/impact bodies, which lays a solid theoretical foundation for the innovative design of the key components of engineering machinery with the contact impact.

潜孔锤多柔体冲击系统由于瞬态接触过程的复杂性，是目前多柔体动力学研究的"瓶颈"问题。本项目采用模态分析、模态截断的离散化技术，针对"活塞-钻头-岩石"组成的多柔体系统，研究其平面接触冲击过程建模理论,通过弹支二柔杆接触冲击控制方程，用分离变量法求解平面接触冲击凿岩模型的通解，用数学力学方法研究边界条件、初始条件及系统参数对柔体接触冲击影响的一般规律，以构建独特的不同于既往研究的柔杆接触冲击模型；对于具有Hertz接触特征的集中参数化建模，针对Hertz接触区特征，采用弹塑性剪切强度理论，构建Hertz接触冲击临界速度的理论，突出强调的是建模的高效率和实用性。通过系统研究，既能丰富弹性支撑二柔杆接触冲击的力学模型通解，又可建立一套多柔体接触冲击建模方法和理论体系，为工程机械具有接触冲击关键构件创新设计打下坚实的理论基础。

潜孔锤/声波钻多柔体振动冲击系统由于瞬态接触过程的复杂性，是目前多柔体动力学研究的“瓶颈”问题。.本项目采用模态分析、模态截断的离散化技术，针对的多柔体系统，研究其平面接触冲击过程建模理论,通过弹支二柔杆接触冲击控制方程，用分离变量法求解平面接触冲击凿岩模型的通解，以构建独特的不同于既往研究的柔杆接触冲击模型，通过钻柱纵向振动的建模与求解，揭示了潜孔锤钻柱共振条件，随着钻孔的延伸，穿岩钻柱的共振区相邻，但不连续，这种系统研究既能丰富弹性支撑二柔杆接触冲击的力学模型通解，又可建立一套多柔体接触冲击建模方法和理论体系，为工程机械具有接触冲击关键构件创新设计打下坚实的理论基础.通过对无惯性边界声波钻进动力学系统的建模，研究了简谐激振力作用下，钻柱稳态受迫振动位移场及其应力场的响应，通过对驻波振动钻柱对岩石瞬态冲击的研究，揭示了声波钻稳态共振的钻柱对岩石的瞬态冲击力的影响及其声波穿岩的机理。有利于工程技术人员合理设计声波钻钻柱系统的级配及其凿岩钻头，也将进一步促进对驻波驻波振子瞬态冲击动力学的理论认识和探索。