I am trying to find the OSI on 3D model on comsol. OSI is defined by following relation: OSI = 0.5(1- (|timeintegration(0,T)of WSS|)/(timeintegration(0,T)of |WSS|)) for clear formula anyone could found on any paper or internet. My issue is that I am applying the formula spf.mu X spf.sr in which i founf the shear stress (WSS) postive and the value in the ratio gives value 1 and answer of plot is 0.
The same issue is finding the shear stress on ant point on point graph. It always gives the postive value. but in actual the value is changing postive and negative in the cycle (w r to 'time')
please solve my problem..