how to find max stress in the picture?
the stress list from 44.5 to 21215 psi with different color, but I can not find the area of max stress 21215 psi in the part.
I didn't see a picture attached to look at, but in 2010 if you Right Click on the Stress Result in the tree and select "Chart Options". There is an option to "Show max annotation". If you select that it should put a flag and pointer to the location of the maximum stress. I would assume the other versions of Solidworks are the same or at least very close in setup.
RIght mouse on your stress plot and "Iso Clipping".
Give this a try. Right click on your Stress results in the simulation tree and select "iso clipping..." A dialogue will appear and you can move the slider to the right and left showing all the areas greater than or less than the value in the "iso value" box. In the design space an arrow will move along the Stress key to show you which stress you are currently "clipping". Simply moving the slider all the way to one end will not work but if you put it very close to the end you should see the region where your stress is increasing. I use this tool a lot to verify that the max stress being reported is true and not some singularity of the modeling or BC's assigned.
Retrieving data ...