This study is concerned with displacement ventilation. The concept of displacement ventilation is explained with an overview of its limitations and conditions for its application. In order to differentiate between displacement ventilation and dilution ventilation, a comparison of the various aspects of the two systems is conducted. The work reviews the literature found on some of the main aspects that need to be studied when designing a displacement ventilation system such as air flow, temperature distribution and other factors. In order to predict the temperature and flow distribution in a room, a CFD model is developed and presented. First a 2-D model is presented in order to compare with the results available in the literature. Comparison between the results of the model developed in this study and the results in the literature show generally close similarities, although slight discrepancies are present which are attributed to the lack of specific knowledge of how the heat produced from the source in the room was simulated. Based on the 2-D model, a 3-D model for the same case study is developed. Comparing the results of both models show considerable differences and demonstrates that simplifying a 3-D into a 2-D model is not justified. Subsequently, an analysis is conducted of the various factors affecting displacement ventilation system in a room. It is found that the temperature gradient in the room changes with increase of heat flux and the vertical location of the heat source. Increasing the room height is also found to affect the temperature distribution and the air circulation in the room. The effect of a hot and a cold ceiling are investigated and so is the effect of heat transfer through a side wall. Finally the effect of the location of the pollutant source on the pollutant dispersion in the room is examined. The results show that having the pollutant source below the heat source results in the most undesirable pollutant distribution in the room.


School of Sciences and Engineering


Interdisciplinary Engineering Program

Date of Award


Online Submission Date


First Advisor

Amr Serag El Din

Committee Member 1

Essam Khalil

Committee Member 2

Salah El Haggar

Committee Member 3

Maher Y.A. Younan

Document Type



73 leaves

Library of Congress Subject Heading 1

Displacement ventilation


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Call Number

Thesis 2005/118



Included in

Engineering Commons