Tracing flow path using FEMLAB
 

Hi, I am trying to simulate fluid flow in a channel with a sink in it using FEMLAB. At any location, the fluid temperature depends on the sink and the sink temperature on the fluid temperature and its flow path. The fluid flow is three dimensional and in order to find the sink at a particular location, I need to track its flow path from the inlet. Can any one of you please help me with any suggestions or any examples. Thank you very much for the help.