Simulation research on the performance of displacement ventilation

• Main Author: Ong, Jing Ning
• Other Authors: Li Hua
• Format: Final Year Project
• Language: English
• Published: 2017
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/71194
• Institution: Nanyang Technological University

Energy saving is an important part of engineering, especially in the design of Heat, Ventilation and Air Conditioning (HVAC) systems. The main objective is to reduce energy consumption so as to lower cost while maintaining the thermal comfort of the occupants. In the past few years, the Computational fluid dynamics (CFD) software has become one of the more popular tools used to simulate the fluid flow in an indoor environment. It has greatly helped engineers in predicting the indoor air flow and also in designing HVAC systems. The aim of this project is to obtain the optimal temperature and velocity air flow distributions for the room. The ANSYS/FLUENT software is used to simulate the displacement ventilation in an enclosed room for this project. Various parameters such as the locations of air inlet, air outlet, the direction of supply air and the presence of an occupant are being simulated and analyzed. At the end of the software simulations, the temperature contour distribution, velocity vector distribution and velocity streamline distribution results are gathered. These results are then analyzed for the effects on thermal comfort and performance for displacement ventilation system. After the three dimensional (3D) simulation, it is found that when the air inlet and air outlet are located at adjacent walls, with the supply air entering at an angle normal to the air inlet, the best thermal comfort is achieved. In addition, the presence of an occupant helps to promote displacement ventilation by aiding in the displacement of contaminated air up to the unoccupied zone. This project helps in the understanding of how the locations of air inlet, air outlet, the direction of supplied air and the presence of an occupant in the enclosed room affects the air flow. The findings of this project is useful to real-life applications.