ContactForceT_Dashpot class

Contents

Description

This is a sub-class of the ContactForceT class for the implementation of the Simple Dashpot tangent contact force model.

This model assumes that the tangent contact force has only a viscous component $F_{t}^{v}$, provided by a linear dashpot.

$$\left \{ F_{t} \right \} = -F_{t}^{v} \{-\hat{t}\}$$

$$F_{t}^{v} = \eta_{t} \dot{\delta_{t}}$$

The tangent damping coefficient $\eta_{t}$ must be provided.

Notation:

$\hat{t}$: Tangent direction between elements

$\dot{\delta_{t}}$: Time rate of change of tangent overlap

classdef ContactForceT_Dashpot < ContactForceT

Public properties

    properties (SetAccess = public, GetAccess = public)
        % Contact parameters
        damp double = double.empty;   % damping coefficient
    end

Constructor method

    methods
        function this = ContactForceT_Dashpot()
            this = this@ContactForceT(ContactForceT.DASHPOT);
            this = this.setDefaultProps();
        end
    end

Public methods: implementation of super-class declarations

    methods
        %------------------------------------------------------------------
        function this = setDefaultProps(this)

        end

        %------------------------------------------------------------------
        function this = setCteParams(this,~)

        end

        %------------------------------------------------------------------
        function this = evalForce(this,int)
            % Force modulus (viscous contribution only)
            f = this.damp * int.kinemat.vel_t;

            % Total tangential force vector (against deformation and motion)
            this.total_force = -f * int.kinemat.dir_t;
        end
    end

end


Published with MATLAB® R2019b