Conical Solar Collector CFD Simulation, ANSYS Fluent

Description

Conical Solar Collector CFD Simulation, ANSYS Fluent Training

Solar energy is the largest source of energy in the world. This energy is clean, cheap, and endless and can be found all over the world. Solar water heaters work by absorbing solar energy from collector plates, and their heating efficiency varies by type of collector. To provide hot water during the day and the night, hot water is kept in a double-sided reservoir with thermal insulation that can keep the water temperature for up to three days without any changes in its temperature.

Conical Solar Collector Project description

In this project, heat transfer in a Conical Solar Collector CFD Simulation containing water fluid is carried out and analyzed by ANSYS Fluent software. The cubic fluid domain consists of an inlet (velocity inlet type, 1m/s) and a pressure outlet. The conical collector consists of an inlet (mass-flow type, 0.0116 Kg/s) and a pressure outlet. It also has 1 layer of glass and 1 layer of steel to decrease convection heat transfer as much as possible. The conical solar collector absorbs the sunlight and warms the water inside its tank. The energy and radiation model (solar ray tracing model) are activated and the Standard model with the use of standard wall function is exploited for fluid flow analysis. Simulations are done for two configurations: water inlet-outlet existence and non-existence (where no water is injected inside the tank and sunlight only warms the water inside the tank).

Conical Solar Collector Geometry and Mesh

The geometry for analyzing this simulation consists of a fluid domain and a conical solar collector. The geometry is designed in ANSYS design modeler® and is meshed in ANSYS meshing®. The mesh type used for this geometry is unstructured and the element number is 577397.

CFD Simulation Settings

The key assumptions considered in this project are:

• Simulation is done using a pressure-based solver.
• The present simulation and its results are transient. 60-time steps with a step size of 60 seconds are exploited for this simulation.
• The effect of gravity has been taken into account and is equal to -9.81 m/s² in the Y direction.

The applied settings are summarized in the following table.

	Models
Viscous model		k-epsilon
	k-epsilon model	standard
	near wall treatment	standard wall function
Energy model		On
Radiation model		On
	Sun direction vector	45 and 90 degrees
(conical solar collector)	Boundary conditions
Inlets
	Water inlet (if exists)	Mass-flow inlet
	Air inlet	Velocity inlet
Water inlet (if exists)	Mass-flow	0.0116 Kg/s
	Temperature	298.15
	Turbulent intensity	5 %
	Turbulent viscosity ratio	10
wind inlet	velocity	1 m/s
	Turbulent intensity	5 %
	Turbulent viscosity ratio	10
Outlets		Pressure outlet
Walls
	wall motion	stationary wall
Adiabatic, adiabatic1, ground, pipe wall	Heat flux	0 W/m2
Steel, glass	Coupled	glass’s thickness = 0.006m
Symmetry		Semi-transparent
(conical solar collector)	Solution Methods
Pressure-velocity coupling		Simple
Spatial discretization	pressure	Second order
	Density	Second order upwind
	momentum	first-order upwind
	turbulent kinetic energy	first-order upwind
	turbulent dissipation rate	first-order upwind
	Energy	First order upwind
(conical solar collector)	Initialization
Initialization method		Standard
	gauge pressure	0 Pa
	velocity (x,y,z)	(0,0,-10) m/s
	Turbulent kinetic energy	0.3750001 m2/s2
	Turbulent dissipation rate	83.74136 m2/s3
	Temperature	298.15 K

Conical Solar Collector Results

Contours of pressure, velocity, temperature, streamlines, and velocity vectors are presented for 4 different configurations.