I am Samanthi, trying to evaluate the ground displacement supported with PIV. I am simulating soil erosion. Soil displacement is comparatively slow but the rate is not constant. Ground is subjected to rapid deformation when I fill water into model and drain out, but all the other time the deformation is slower. When I choose two images with considerable ground displacement usually time gap between images is changing from minutes to hours. The problem is with calibrating the model. Still I convert the hours to milliseconds and perform calibration.
I am interested about evaluating ground deformation, not the velocity or the vorticity. In that case, I have to multiply those velocities with the time gap between images to back calculate the deformation. But I know that the velocity I have got was not constant throughout the period and most of the displacement was caused during a short period of time. Do you think it is accurate to multiply the velocity and the time to get the actual displacement, or is there any other way that I can just calibrate the images and find the displacement?
I have attached two photos of my model for your understanding and I am really grateful if you can help me with this.
what about not calibrating your data at all? then PIVlab will output the "velocity" in pixels per image pair. It is probalby easy to transform that to a displacement in meters (just determine once how many meters are in one pixel and multiply everything by that value).