Conjugate Heat Transfer Simulation

Objective:

- Simulation of Conjugate Heat Transfer in a solid pipe

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Case setup:

Solid: Aluminium

Fluid: Air

start Time: 0 s

End Time: 0.5 s

Inlet velocity: 3.64 m/s

Outlet Pressure: 1 bar

Super-cycle Modelling:

Time length of each cycle: 0.05

Base grid: 0.004, 0.002,0.0015

Calculation of Inlet velocity:

The density of Air: 1.184 kg/m3

Dynamic viscosity of air : `1.84 *10^(-5)(kg)/(ms)`

Reynolds number = 7000

from the calculation; velocity = 3.64 m/s

Mesh:

Grid size: 4e-3m

Grid size: 2e-3m

Grid size:1.5e-3m

Grid Dependence test for the following Three base Meshes:

Temperature:

The temperature contour is been shown on the above, It is observed that the flow is taking place in the z-direction. It is also seen that the formation of the thermal boundary layer where the fluid and the solid interacts. As the Mesh is refined to a small size, the thermal boundary layer was captured.

Super-Cycling:

In solid, the time scale for heat transfer is usually greater than that of the fluid. It takes a larger time to get into the steady-state simulation. Converge offers an acceleration technique to solve such criteria. It is usually done in the combustion process for eg: in Engines, it takes greater time to the engine material to get into a steady state. To overcome this issue, super cycling is used. The three different supercycling intervals are used to analyze the difference. The three different supercycling intervals are 0.01, 0.02, 0.03. It is observed that the less interval converges faster than that of the other intervals.