Forward-Backward streamline
 

Hi, everybody !

I could understand forward streamline on a plane. But I could not understand backward streamline on a plane. I would like to request sharing knowledge about backward streamline from someone with an example. Or, I look forward to some references about backward streamline. Thank you very much.

Hi Tunlu,
From the way I use it, in CFView, the backward option in the definition of a streamline is nothing else than the possibility to find the streamline upstream of a given point in the domain. In general if one wants to define a streamline, its location needs to be somehow specified and often this is done by a starting point from which the streamline is computed in forward/streamwise or backward/upstream direction. Or, at least in CFView, the streamline can be computed from the starting point in both directions.

Maybe you got confused by the word backward thinking it would refer to the flow direction? A 'backward streamline' has still the streamwise flow direction. Backward only refers to the direction of computing of the streamline.

Hi, Colinda,
Thank you very much for your explanation. As you siad, I get confused with the meaning of backward. So, how can I understand, if I see combination of forward and backward streamline on a plane? Thank a lot.

Once the streamline is generated, there is no further meaning to forward and backward. There is nothing different in the backward or forward part... it is only at the moment you create the streamline: you need to select a location where you want to construct the streamline and then forward means you will construct the streamline further downstream from the selected point and backward refers to the construction of the streamline upstream of the selected point.

Hi Colinda
Thank you so much for your valuabe explanation.