I follow this to make streamlines like the photos attached below: (software- CFD post-processing) First I plot the 2D streamline over a surface "streamline 1". them I plot a vector by the following properties: Locations "streamline 1" But by choosing the streamline as location, no vector shown over the streamlines. Moreover, Arrowhead I try to use the Symbol tab of streamline to show the Arrow head from there, but the problem there is that, there is no option to plot symbols tangentially since the streamline is plotted in 2D.