Dear All,
I simulated a simple laminar flow of a liquid metal inside a 1 inch tube of 0.5m length with a constant heat flux acting at its wall in comsol 4.2. I used both the mesh options i.e. the automatic mesh option based on the physics controlled mesh featured in v4.2 and also the manual mesh option, however in both cases the temperature at the wall comes out to be less than the bulk liquid temperature at that axial location which is giving a Nusselt number value that does not matches with the theory at all. Can some one identify what is wrong? (Note that in a short tube of 0.5m length the flow always remains developing and therefore the Nusselt number must remain higher than the value of 4.36 (Fully developed laminar flow) at each axial location.
Kindest regards.
I simulated a simple laminar flow of a liquid metal inside a 1 inch tube of 0.5m length with a constant heat flux acting at its wall in comsol 4.2. I used both the mesh options i.e. the automatic mesh option based on the physics controlled mesh featured in v4.2 and also the manual mesh option, however in both cases the temperature at the wall comes out to be less than the bulk liquid temperature at that axial location which is giving a Nusselt number value that does not matches with the theory at all. Can some one identify what is wrong? (Note that in a short tube of 0.5m length the flow always remains developing and therefore the Nusselt number must remain higher than the value of 4.36 (Fully developed laminar flow) at each axial location.
Kindest regards.