In this dissertation , a method to generate 2 - d unstructured grid and the finite volume arithmetic to solve two - dimensional euler equation in unstructured grid system are investigated in detail . the codes are also developed for grid generator and euler solver , and the calculation results are compared with experimental data 本文主要研究二维非结构网格的生成方法和基于非结构网格的euler方程有限体积算法;研制开发了非结构网格生成及euler方程数值算法的程序软件,并将计算结果与实验结果进行了对比分析。
This paper did some research on the position control of this kind of robot , mainly finished the work as below : firstly , we use newton - euler equation build a dynamics model of the underactuated robot , then , we simplify the model through obtaining the average system of the underactuated robot using averaging method which is efficient to deal with nonlinear system 本文以该类机器人为研究对象,进行了位置控制的研究,主要完成了以下几方面的工作:首先,利用牛顿欧拉方程方法,即用力和动量、力矩和动量矩描述刚体的动力学性能方法,建立具有非驱动关节的两关节机器人动力学模型。
In this thesis , finite volume method and dual - time stepping method are employed to solve the 3 - d unsteady euler equations . the unsteady flow field around a finite - span flapping wing is simulated . the lift and thrust of the flapping wing for different cases are calculated 本文运用有限体积法结合双时间推进技术求解三维非定常欧拉方程,模拟了有限翼展机翼在同时具有上下拍动和俯仰运动状态下的非定常流场,计算了不同状态下扑翼的升力及推力,分析了各个影响因素对扑翼气动特性的影响。
There are two main ways that will be effective to solve the question currently : one is to improving numerical algorithm by all kinds of skills to accelerate convergence ; the other is to introducing parallel computing . in order to work out the numerical simulation of flow in naca0012 , euler equations are selected as the control equations of the flow field in this paper 目前解决问题的主要途径有两条:一是改善数值方法,利用各种收敛技术来减少计算时间;二是利用并行环境,实现软件的多机并行计算,达到大幅度降低计算时间的目的,使得某些巨型计算成为可能。
The present thesis utilizes the fundamental theorem of conservation numerical difference schemes converging to weak solutions , constructing euler equations numerical parallel algorithms of overlap sub - domains and connected sub - domains , and making sure the numerical parallel value converging to weak solutions of euler equations , in other words , parallel numerical schemes are conservative 本文利用守恒型数值差分格式能收敛到方程弱解这一基本定理,对重叠分区和对接分区构造数值并行算法,使并行数值计算也能收敛到欧拉方程的弱解,即使并行后的总体数值格式是守恒的。
Only clouds of points instead of grids are distributed over the computational domain and the spatial derivatives are estimated using a least - square curve fit on local clouds of points . the paper gives discrete form for euler equations on base of gridless method , and adopts five steps runge - kutta scheme for time - marching . the numerical results have been obtained for the 2 - d flows over airfoils or multi - element airfoils using the method presented 本文首先对无粘euler方程进行无网格离散,并运用显式runge - kutta格式推进求解,成功地数值模拟了二维单段和多段翼型的绕流;在此成功的基础上通过在euler方程的右端加入粘性项,使求解方程变为层流navier ? stokes方程,得到了翼型绕流,数值结果显示出粘性的影响。
The schemes are numerically tested on a variety of id and 2d problems ; solutions obtained in computation the results of the numerical solutions for euler equation and shallow water equations by gauss schemes presented in the paper under distributed memory parallel multiprocessor are presented . the efficient of parallel computation are satisfied 利用曙光- 1000型分布存储大规模并行机,对我们在交错网格下所构造求解euler方程和浅水方程的高分辨差分格式进行了并行实现,并对并行效率进行了分析,计算结果和并行效率都比较令人满意。