Air Conditioning of Room with Balcony by Solar Radiation, ANSYS Fluent

Air Conditioning Project description

There are many types of air conditioning and ventilation systems used in buildings. The use of any ventilation system depends on the location of the building and the climatic zone of the desired location. Sunlight plays an important role in the temperature of the walls as well as the air temperature inside the building and this issue should be considered when designing the ventilation system.

In this project, heat transfer inside a room and a balcony is investigated. The balcony has a glass roof and one glass wall. Due to the radiation of sunlight, both room and balcony become warmer and natural convection plays an important role in circulating the flow inside these spaces. The standard k-epsilon model is exploited for solving turbulent flow equations and P1 solar tracing model is used for simulating the solar rays entering the computational domain and the energy model is activated to calculate the temperature distribution in the domain. it should also be pointed out that ideal-gas law is used to account for the changes in density due to temperature changes.

Geometry and mesh

The geometry for analyzing this simulation consists of a room and a balcony. The geometry is designed in ANSYS design modeler® and is meshed in ANSYS meshing®. The mesh type used for this geometry is structured and the element number is 290250.

Air Conditioning CFD simulation settings

The key assumptions considered in this project are:

• Simulation is done using pressure-based solver.
• The present simulation and its results are steady.
• The effect of gravity has been taken into account and is equal to -9.81 m/s² in Z direction.

The applied settings are summarized in the following table.

(Air Conditioning)	Models
Viscous model		k-epsilon
	k-epsilon model	standard
	near wall treatment	standard wall function
Energy model		On
Radiation model		P1
	Solar ray tracing	Used solar calculator
(Air Conditioning)	Boundary conditions
Walls
	wall motion	stationary wall
glass1, glass2, glass3	Thermal condition	Convection
	Heat transfer coefficient	20 W/m2K
	Free stream temperature	310 K
	Radiation	Semi-transparent
Wall-argon, wall-zone, wall-room	Thermal condition	Convection
	Heat transfer coefficient	20 W/m2K
	Free stream temperature	310 K
	Radiation	opaque
Wood	Thermal condition	Coupled
	Radiation	opaque
(Air Conditioning)	Solution Methods
Pressure-velocity coupling		Simple
Spatial discretization	pressure	Second order
	momentum	second order upwind
	turbulent kinetic energy	first order upwind
	turbulent dissipation rate	first order upwind
	Energy	second order upwind
(Air Conditioning)	Initialization
Initialization method		Standard
	gauge pressure	0 Pa
	velocity (x,y,z)	(0,0,0) m/s
	Turbulent kinetic energy	1 m2/s2
	Turbulent dissipation rate	1 m2/s3
	Temperature	310 K

Air Conditioning Results

After the simulation process, the contours of pressure, velocity, temperature, etc. are extracted and presented. As can be seen in streamline contours, since we do not have any external flow, the natural convection is responsible for circulating the flows in the room and balcony.

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