Changeset 17390

Timestamp:

03/07/14 13:28:15 (11 years ago)

Author:

cborstad

Message:

CHG: added some comments to clarify stress calculations

File:

• issm/trunk-jpl/src/m/mech/mechanicalproperties.m (modified) (4 diffs)

issm/trunk-jpl/src/m/mech/mechanicalproperties.m

@@ -2 +2 @@
 %MECHANICALPROPERTIES - compute stress and strain rate for a goven velocity
 %
-%   this routine computes the components of the stress tensor
-%   strain rate tensor and their respective principal directions.
-%   the results are in the model md: md.results
+%   this routine computes the components of the (deviatoric) stress tensor,
+%   the strain rate tensor, and their respective principal directions.
+%   The results are in the model md: md.results
 %
 %   Usage:
@@ -107 +107 @@
 %plug onto the model
 %NB: Matlab sorts the eigen value in increasing order, we want the reverse
+%NOTE: all stresses below are deviatoric
 stress=struct('xx',[],'yy',[],'xy',[],'principalvalue1',[],'principalaxis1',[],'principalvalue2',[],'principalaxis2',[],'effectivevalue',[]);
 stress.xx=tau_xx;
@@ -115 +116 @@
 stress.principalvalue2=valuesstress(:,2);
 stress.principalaxis2=directionsstress(:,3:4);
-stress.effectivevalue=1/sqrt(2)*sqrt(stress.xx.^2+stress.yy.^2+2*stress.xy.^2);
+stress.effectivevalue=1/sqrt(2)*sqrt(stress.xx.^2+stress.yy.^2+2*stress.xy.^2); % effective shear stress
 md.results.stress=stress;
 
@@ -129 +130 @@
 md.results.strainrate=strainrate;
 
+%exact same stress as above
 deviatoricstress=struct('xx',[],'yy',[],'xy',[],'principalvalue1',[],'principalaxis1',[],'principalvalue2',[],'principalaxis2',[],'effectivevalue',[]);
 deviatoricstress.xx=tau_xx;