Serrated Finned Tubes Heat Transfer CFD Simulation

Description

Problem Description for Heat Transfer Over Serrated Finned Tubes CFD Simulation

The present product is going to simulate a cool airflow over a serrated fin and compare the results of numerical work (CFD) with the results of the paper entitled: “A characteristic correlation for heat transfer over serrated finned tubes.”

The Assumption for Heat Transfer Over Serrated Finned Tubes CFD Simulation

There are several assumptions used to simulate the present problem:

The solver is based on a pressure-based perspective.
The simulation is Steady-State.
The turbulence flow is considered.
The effect of Earth’s gravity has been ignored.

Geometry & Mesh

The pipe and blade model was first designed in SOLIDWORKS software and later imported into the ANSYS Design Modeler software. After the changes were made, the model was ready to have been meshed. The grid used in the fin areas as well as between them is structured and in other areas it is unstructured. The total number of elements used is 356240.

Heat Transfer Over Serrated Finned Tubes CFD Simulation

Summaries of the problem definition and problem-solving steps are presented in the following table:

Models
k-epsilon	Viscous model
RNG	k-epsilon model
Enhanced Wall Treatment	Near wall treatment
on			Energy
Boundary conditions (Heat Transfer over Serrated Finned Tubes)
Velocity inlet	Inlet type
1.825918367347 m/s	Inlet velocity		(Heat Transfer over Serrated Finned Tubes)
1%	Turbulent Intensity
10	Turbulent Viscosity Ratio
313.15 K	total temperature
Pressure outlet	Outlet type
0 Pa	gauge pressure
1%	backflow Turb. Int.
10	backflow Turb. Vis. Ratio
313.15 K	backflow total temperature
wall			Walls type
473.15 K	Const. temperature for walls
0 W.m-2	heat flux for walls
Solution Methods (Heat Transfer over Serrated Finned Tubes)
Simple			Pressure-velocity coupling
Second Order	pressure		Spatial discretization
Second order upwind	momentum
Second order upwind	energy
Second order upwind	turbulent kinetic energy
Second order upwind	turbulent dissipation rate
Initialization (Heat Transfer over Serrated Finned Tubes)
Standard	Initialization method
1.825918 m/s	X- velocity
0.0005000967	Turb. Kinetic energy
0.0001446749	Turb. Dissipation rate
300 K	temperature

Boundary Condition (Heat Transfer over Serrated Finned Tubes)

Inlet

At the inlet of this pipe, air enters with a constant velocity of 1.83m/s and a temperature of 313.15K.

Wall

The condition assumed, according to the paper, is a constant temperature condition of 473.15K.

Symmetry

According to the model, the symmetric boundary condition for geometry is taken into account.

Outlet

The condition applied in this section is the pressure outlet.

Reference Value

Since in this case, the fluid and thermal parameters after passing through the blades are compared with the fluid and thermal parameters at the inlet of the solution domain, so the reference value values should be considered the same as the pipe inlet values.

Results of Heat Transfer Over Serrated Finned Tubes CFD Simulation

After the dissolution process is completed, two-dimensional temperature contours are obtained for 3 different Reynolds. In the following, the Nu graph in different Re numbers is given by comparing the graphs obtained from numerical (CFD) and experimental work to verify the accuracy of the numbers reported in the present project.

The error in all three Reynolds is given in the table below, with a total error of less than 10%.

Re	Nu(Present)	Nu(Paper)	Error (%)
2000	9.20664	8.5	7.675333
5000	16.79145	19	13.15283
10000	26.31589	28.5	8.299582
Net			9.709249

There is a mesh file in this product. By the way, the Training File presents how to solve the problem and extract all desired results.