CFD studies for energy conservation in the HVAC system of a hatchback model passenger car

ABSTRACT

Heating, Ventilation and Air Conditioning (HVAC) system of a passenger cabin in a vehicle is a largest auxiliary load in an automobile, apart from primary tractional load. A larger energy for HVAC system can reduce the driving range of an electric vehicle. The same condition may result in increase in fuel consumption of an engine-driven vehicle up to 25%. Excessive heating up of the passenger compartment is primarily caused by exposure of the vehicle to peak solar radiation. Energy conservation studies will reduce the energy consumption as well as initial size of cooling system. In the present work, the CFD analysis of a HVAC system in a hatchback car model has been carried out. The analysis was executed to find the baseload and temperature rise in an automobile passenger cabin without cooling. Following this, the cooling process has been implemented in the CFD model. Energy conservation measures, such as implementation of different types of insulation materials and window blinds have been carried out to study the temperature reduction by insulations and window blinds in the car cabin. The interior fluid domain of the car cabin has been modeled and simulated using ANSYS FLUENT 19.0 software. Results obtained from various simulations revealed the usefulness of the CFD simulation tool in studying the various parameters that are responsible for energy consumption in an automobile. The results taken from the simulation can be used by vehicle manufacturers for their vehicle advancement and they can develop a CFD model for optimizing the HVAC energy in an automobile.

KEYWORDS:

• HVAC
• solar radiation
• hatchback model
• electric vehicle
• energy conservation
• CFD

Acknowledgments

This work has been done in the DST-IPHEE CFD Laboratory of Easwari Engineering College, Ramapuram, Chennai, India.

Nomenclature

ρ	=	density (kg/m3)
U	=	mean flow velocity (m/s)
t	=	time (s)
x	=	distance (m)
P	=	pressure (Pa)
τ	=	shear stress (N/m2)
g	=	gravity (m/s2)
µ	=	dynamic viscosity (kg/m.s)
λ	=	thermal conductivity (W/m2K)
Γ	=	diffusion coefficient (m2/s)
q	=	heat flux (W/m2)

Additional information

Notes on contributors

Hariharan. C

Hariharan. C is an Assistant Professor in the Department of Automobile Engineering at Easwari Engineering College, Chennai. He completed his Post Graduate in Automobile Engineering at Madras Institute of Technology, Chennai. He is specialized in CFD and doing his research in the field of HVAC system of an automobile.

Sanjana. S

Sanjana. S is an undergraduate student of Department of Mechanical Engineering at Easwari Engineering College, Chennai. She is proficient in using CFD software.

Saravanan. S

Saravanan. S is an undergraduate student of Department of Mechanical Engineering at Easwari Engineering College, Chennai. He is proficient in using CFD software.

Shyam Sundar. S

Shyam Sundar. S is an undergraduate student of Department of Mechanical Engineering at Easwari Engineering College, Chennai. He is proficient in using CFD software.

Arun Prakash. S

Arun Prakash. S is working as a Junior Research Fellow in the Department of Mechanical Engineering at Easwari Engineering College, Chennai. He completed his Post Graduate in Energy Engineering at Pondicherry Engineering College. He is doing research in the field of CFD simulations in Buildings.

Antony Aroul Raj. V

Antony Aroul Raj. V is Professor in the Department of Mechanical Engineering at Easwari Engineering College, Chennai. He received his doctorate degree from Anna University, Chennai. He completed his Post Graduate in Energy Engineering at Pondicherry Engineering College. He is specialized in Computational Fluid Dynamics application in the fields of drying, renewable energy, buildings and automobile.