Hi, in V4.3 the Particle Evaluation feature under Derived Values was introduced:
www.comsol.com/products/4.3/#particletracing
This allows you to write the numerical value of an expression into a Table for the particles. You can then use the Graph Plot option to plot this data. This means you can plot particle position etc. v.s. time in 1D plots and isolate individual particles. If you want to plot particle position v.s. particle velocity on the same plot you should use a phase portrait. Both are demonstrated in the attached model.
If you want to compute tortuosity for particles you would probably need to add an auxiliary dependent variable and solve an additional ODE for the curvature of the trajectory. This sounds either very difficult or impossible.
www.comsol.com/products/4.3/#particletracing
This allows you to write the numerical value of an expression into a Table for the particles. You can then use the Graph Plot option to plot this data. This means you can plot particle position etc. v.s. time in 1D plots and isolate individual particles. If you want to plot particle position v.s. particle velocity on the same plot you should use a phase portrait. Both are demonstrated in the attached model.
If you want to compute tortuosity for particles you would probably need to add an auxiliary dependent variable and solve an additional ODE for the curvature of the trajectory. This sounds either very difficult or impossible.