Investigation of the Vehicle Mobility in Fording

Abstract

This contribution concerns a general purpose fluid-multibody system (MBS) simulation framework that can be used to analyze the fluid-solid, two-way coupled dynamics at low to medium Reynolds numbers (0 < Re < 1500). The simulation framework can be leveraged to investigate MBS applications that include (i) rigid and flexible bodies of arbitrary geometry; (ii) bilateral constraints (joints); (iii) unilateral constraints associated with impact and contact phenomena; and (iv) friction/cohesion.The fluid dynamics problem is formulated using the fluid momentum and continuity, i.e., Navier-Stokes equations. These equations are spatially discretized via a weakly compressible smoothed particle hydrodynamics (SPH) Lagrangian method [1], which relies on moving markers to store state information associated with fluid phase. The space dependent variables, such as velocity and pressure, are smoothed out locally via a scalar function. That is, to obtain a variable, a gradient, or a hydrodynamics force at an arbitrary location of the domain, one needs to account for partial contributions coming from nearby markers. External forces such as fluid-solid interaction (FSI) force are added to the hydrodynamics force. The fluid equations of motion, which upon spatial discretization become a set of ordinary differential equations, are solved explicitly using a second order Runge-Kutta integration method.Of several approaches that have been considered in the literature to model the fluid-solid coupling, we show that using a point-cloud discretization of a solid results in an accurate calculation of the fluid-solid coupling forces [2]. In this approach, the MBS dynamics is solved by providing the solver with distributed forces captured by the point cloud representation.

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Document Details

Document Type
Technical Report
Publication Date
May 29, 2016
Accession Number
AD1011188

Entities

People

  • Arman Pazouki
  • Dan Negrut
  • Paramsothy Jayakumar

Organizations

  • United States Army Tank Automotive Research, Development and Engineering Center

Tags

DTIC Thesaurus Topics

  • Computational Science
  • Data Transmission
  • Differential Equations
  • Dynamics
  • Engineering
  • Equations
  • Equations Of Motion
  • Fluid Dynamics
  • Graphics
  • Graphics Processing Unit
  • Hydrodynamics
  • Mechanical Engineering
  • Navier Stokes Equations
  • Parallel Computing
  • Point Clouds
  • Reynolds Number
  • Simulations

Readers

  • Computational Fluid Dynamics (CFD)

Technology Areas

  • Space