rolling_radius.m

Matlab中实现轮对分析的程序以及相关的程序包,可以实现火车轮轨接触关系的分析

% M-file name: rolling_radius.m
% M-file type: Function file

% This function file computes the rolling radii at the left and the right wheel-rail contact
% patches as a function of the relative lateral displacement between the left and the right wheels
% and rails. The inputs to the function are the relative lateral displacement between the left

% wheel and the left rail and the right wheel and the right rail. The outputs are the rolling radii
% at the left and the right tread and flange contact patches.
% The outputs given by this function are called by the function file 'wheelset.m'.

function [rlefttread,rleftflange,rrighttread,rrightflange]=rolling_radius(y,yl,yr)

% Parameters used for simulation
% yfc: Flange clearance or flange width (m)
% yfctol: Lateral tolerance added to yfc in order to facilitate numerical simulation (m)
% r0: Centered rolling radius of the wheel (m)

% Indicating the global nature of the variables This means that the value of the variables need % not be specified in this function file. This value is automatically obtained from the main file % 'single_wheelset.m'. 
global yfc yfctol r0; 
% Computing the rolling radii at the left and the right wheel-rail contact patches. These variables
% are passed to the function 'wheelset' .
if y>=0

% Wheelset displacement is in the positive (or left) direction from the centerline (Right 
% wheel tread contact)
% Note that for a left movement of the wheelset from the centerline, the
% right wheel does not flange. Hence, the zero value for the right wheel
% flange radius is not real and is not used in calculations.

rrighttread=r0+0.125*(yr);
rrightflange=0.000;

if yl<=yfc 
% Left wheel tread contact. Note that the zero value for the left wheel flange radius is not % real and is not used in calculations. 
rlefttread=r0+0.125*yl;
rleftflange=0.000;
elseif yl<(yfc+yfctol)
% Left wheel flange contact

rlefttread=r0+0.125*yl;
rleftflange=0.3566+13700*(yl-0.008)^2;
else

% Left wheel two-point contact
rlefttread=r0+0.125*yl;
rleftflange=0.3703+2.5833*(yl-0.009);

end 
else 
% Wheelset displacement is in the negative (or right) direction from the centerline (Left
% wheel tread contact)
% Note that for a right movement of the wheelset from the centerline, the

% left wheel does not flange. Hence, the zero value for the left wheel

% flange radius is not real and is not used in calculations.
rlefttread=r0+0.125*yl;
rleftflange=0.000;

if yr<=yfc 
% Right wheel tread contact. Note that the zero value for the right
% wheel flange radius is not real and is not used in calculations.
rrighttread=r0+0.125*(yr);

rrightflange=0.000;
elseif yr<(yfc+yfctol)
% Right wheel flange contact
rrighttread=r0+0.125*yr;

rrightflange=0.3566+13700*(yr-0.008)^2;
else
% Right wheel two-point contact

rrighttread=r0+0.125*yr;
rrightflange=0.3703+2.5833*(yr-0.009);
end

end