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ASSIGNMENT

ON

ANALYSIS OF AIR FLOW IN AND AROUND THE

SCHOOL OF EARTH AND MINING SCIENCE

FACULTY

LOCATED ALONG ODUDUWA ROAD OBANLA IN

FEDERAL UNIVERSITY OF TECHNOLOGY AKURE. ONDO STATE.

COMPILED BY

SOYOBI O.A

ARC/03/1957IN PARTIAL FULLFILMENT OF THE AWARD

M-TECH IN ARCHITECTURE

LECTURER IN CHARGE: PROF. O.O OGUNSOTE

APPLIED CLIMATOLOGY

ARC 810

AUGUST, 2011.

TABLE OF CONTENT

ABSTRACT

CHAPTER ONE

1.O INTRODUCTION

1.2 AIMS OF THE STUDY

1.3 SCOPE AND METHODOLOGY

CHAPTER TWO

2.0 FACTORS THAT INFLUENCE THE AIR FLOW

THROUGH THE BUILDING

2.1 OPENING COMPONENTS

2.2 EXTERNAL FEATURES & FACTORS

2.3 ORIENTATION OF THE BUILDING

2.4 POSSITION OF OPENINGS

2.5 NUMBER AND SIZE OF OPENINGS

CHAPTER THREE

3.0 ABOUT THE BUILDING ‘SMES’

3.1 AIR FLOW THROUGH THE BUILDING

3.1.1 THE STACK EFFECT

3.1.2 AIR MOVEMENT INDUCED BY WIND PRESSURE

3.1.3 MECHANICAL MEANS

CHAPTER FOUR

4.0 CONCLUSION

REFERENCE

ANALYSIS OF AIR FLOW IN AND OUT OF SEMS’

ABSTRACT

Air flow in a building can be achieved through mechanical means such as fans,

evaporative coolers, air conditioners and heater, air movement induced by wind pressure, and the

stack effect due to difference in temperature between the air within and outside the building.

The source”, which supply of fresh air, body cooling and the likes will be describe. Air flow of a

building and around its: is determined by the orientation, shape, height and planning of external

features and factors such as trees, vegetation, walk way, shrubs, flowers etc.

The studied will emphases on this factor that influence the Air flow in the building and around

the ‘SEMS’ building. A conceptual savvy of this basic concept of Air flow in the building and

the environment will be analyze.


1.0 INTRODUCTION

In any building design development by an Architect primarily aimed at

enhancing good comfort and functional for the occupants through the spacing and the

height of the building and he can also achieved it by introducing some mechanical means

such as fans, air conditioners, or evaporative coolers and putting some elements of

building like windows, doors and externals features like planting of landscaping such as

trees, shrubs, flowers and soon on .

Air flow in a building is the circulation of inside air generated from mechanical

means such as fans, evaporative coolers, air conditioners and also by outside air and it

has some functions that provides body cooling and structural cooling or heating. Air

movement through the buildings can be induced by the stack effect, wind pressure or by

the mechanical means. The factor that affect Air flow through the buildings are external

features are number and size of openings, position of opening components. The Air flow

around the building is determined by the shape, orientation, height and planning of

building i.e landscaped features in the external perspective.

1.2 AIMS OF THE STUDY

This is the study of Air flow in ‘SMES.’ School of Earth and Mineral Sciences

located along Oduduwa road inside Federal University of Technology Akure. It aims at

examining the Air flow conditions in the building and the environment, its functioning to

its purpose served and the use of mechanical means in effectively use for the users. In

addition , external features, that were not sufficiently dealt with in the construction stage

and others that have arisen over the years of occupation will be identified and solutions to

alleviate them will be proffered.


1.3 SCOPE AND METHODOLOGY

This studied is one which is very explanative about the air flow in the building

and external features which give more adequate air flow and affirmative assertions to the

building. Hence, a visit to the study centre to be considered was the first step taken with

very vital and inquisitive question asked about different area. Also, relevant books and

websites were consulted so as to critically consider this important phenomenon.


CHAPTER TWO

2.0 FACTORS THAT INFLUENCE THE AIR FLOW THROUGH THE BUILDING

There are different factors that influence the air flow in the building which will be

vividly enunciated and with the barriers that can be use to control them is been done.

Some of these are:

2.1 OPENING COMPONENTS

These components are part of element of building that enhance the steady air flow into

the building . Opening components are important in determining the velocity and pattern of air

flow. These components include Canopies (i.e horizontal shading devices), Louvres and venetian

blinds, Sashes, variously hung windows, mosquito screens, curtains.

Canopies direct the air flow towards the ceiling but this can be reversed towards the floor

by leaving a gap between the canopy and the opening. Louvres and venetian blinds direct the air

flow upwards or downwards according to their angle of inclination. Sashes deflect the air flow

upward but reversible pivot sashes can deflect it downwards. Top hung outward-opening

windows deflect air towards the ceiling. Side hung outwards and vice-versa. Roller shutters

deflect wind downwards when partially open. Mosquito screens and curtains reduce air flow to a

very large extent. Mosquito screens, depending on material and perforation. May reduce air flow

by 30% to 70%. For nylon screens, reduction is about 35%. This should be kept in mind when

calculating size of openings for effective air flow.

2.2 EXTERNAL FEATURES & FACTORS

The air flow in buildings is affected by external features and factors. The wind speed and

direction as well as dust content combined with the building shape and orientation are extremely

importance. Dusty winds should be avoided or filtered by vegetation. Building orientation should

take maximum advantage of wind direction. External features such as barriers and vegetation

also play an important role as they may create wind shadows and channel air flow. The situation

of the wind shadows and achieve air movement.


2.3 ORIENTATION OF THE BUILDING

This is the positioning of the design development through the wind flow from South-

West Zone from the inception stage of the project. This air flow can be achieved by positioning

longer side along North cardinal point and these was also applied on the building ‘SEMS

Building’ and this really enhance good air flow through the building

2.4 POSSITION OF OPENINGS

The position of outlets (on the leeward side) and that of inlets (on the windward side) has

a marked effect on the pattern of air flow within an enclosure. This influence can be observed

both in plan and section .

In design plan, the air velocity distribution is affected by the relative of inlet and outlet

for a given wind direction. The incoming air stream takes the shortest course of least resistance

to the outlet. Thus openings located diagonally will cause air flow through the centre of the

office.

2.5 NUMBER AND SIZE OF OPENINGS

To achieve a good air flow in any building there should be an effective cross ventilation

there be at least two openings, an inlet and an outlet, on opposite, or at least adjacent walls of an

enclosure . Furthermore, there should be no full partition separating the inlet from outlet. In a

case where is only one opening, the air movement within the room remains negligible even for

high external winds speeds. In fact, comfort conditions worsen at higher wind speeds due to

pressure build up around the building.


CHAPTER THREE

3.0 ABOUT THE BUILDING ‘SEMS’

The School of Earth and Mineral Sciences study is located along the Oduduwa

road beside the PGD hall building. It is strategically located on a topography hump

which meant to be one of the beautiful and sound design among millions of them in the

school premises. It is a centre for Service to human kind and self reliance esteem. This

building was design by one noble Architect in Federal University of Technology Akure.

Ondo state in person of Prof.O.O Ogunsote. This building was commissioned by the

formal President Olusegun Obansanjo.

The facade view of the School of Earth and Mineral Sciences ‘SEMS’


The facade view of the School of Earth and Mineral Sciences ‘SEMS’

The entrance showing the commissioned date.


The one part of the building full landscape which enhance good

Fresh air and body cooling during.


The other part of the building been step down

from the entrance

The corridor part of the building and Doric order of the structures.


The walk way that leads to the building SEMS” External features

The external view showing a good landscaped area and fins

which served as a shading devices to the offices or recess.

3.1 AIR FLOW THROUGH THE BUILDING

3.1.1 THE STACK EFFECT


The effect refers to the movement of air as a result of differences in air pressure of two

bodies of air at different temperatures. Thus when there is a significant difference in the

temperature of air within and outside a building possessing appropriate air inlets and outlets, air

movement results. If for example the temperature outside the building is lower than that inside,

then cold air will enter through the lower inlet and warm air will arise and exit through the lower

inlet warm air rise and exit through the upper outlet. The rate of air flow achieved is directly

proportional to the area of the inlet, and the square root of the difference in temperature between

inside and outside air, and the difference in height the inlet and outlet. The rate of Air flow is

affected by the ratio of the area of outlet to area of inlet. The ratio determines the correction

factor.

In Akure, stack effect usually produces some air movement even for small differences in

temperature and height. In warm humid condition such as Ondo, Warri, Port-Harcourt, Calabar,

and Lagos. The climatic is characterized by high humidity and hot discomfort. Stack effect

cannot be relied upon to provide adequate cooling by air movement even with large window.

The SEMS’ building openings are relatively small but since the design was facing the windward

side of buildings with outlets on the leeward side. The difference in height between inlet and

outlet should be maximized. The outlet was big enough to accommodate more features and

adequate cooling by air movement through the building.

3.1.2 AIR MOVEMENT INDUCED BY WIND PRESSURE

Here, wind pressure is the major force responsible for air flow through building. The air

movement produced by stack effect is often of little magnitude and insufficient for body cooling.

Wind pressure and stack effect often act together to create air movement within the buildings.

The use of mechanical aids is usually employed only if the air movement induced by wind

pressure and stack effect is insufficient.

The aim of design is usually to maximize wind pressure for air flow, especially in the

warm humid climate in the Southern-West part of the country. The exception to this rule includes

situations where the wind is dusty, cold and unwelcome, such as is experienced during the

harmattan. There are also cases where the wind is so strong that it causes destruction,

Tearing roofs off buildings for example in Sokoto.


3.1.3 MECHANICAL MEANS

These are used mainly in the building and also with the help of number of openings in

each office which aid the comfort requirement. These aids therefore often provide.

Air movement

Cooling

Heating

Humidification or dehumidification

These mechanical aids are fans, evaporative coolers, air conditioners and heaters.

FANS:Electric fans are very useful in providing necessary air movement for body cooling,

especially in the warm humid climates in the Southern-Western part of the country. Types of

electric fans include ceiling fans, wall mounted fans, standing fans, table fans and extract fans.

Extract fans cannot be used for body cooling since they suck and do not blow air: may however

be used to assist the stack effect and remove odours and vapours.

The type electric fan they use in SEMS’ are mainly Ceiling fan and the cooling system

Air conditioners in some offices.

AIR CONDITIONERS:

Air conditioners provide both cooling and humidification and are sometimes the best

solution in difficult climates especially for offices and public buildings. Their major drawback is

cost of acquisition and maintenance. Air conditioners may be large plants, small unit or split

units . The use or otherwise of air conditioning should be decided early in design since this will

affect the size of openings. The use of Air conditioners is also applicable in the School of Earth

and Mineral Sciences.


4.0 CONCLUSION

Air flow in a building is extremely important and should be given prime

consideration in any design development and construction so as to aid good comfort and

functional for the purpose its meant to serve for the users through the spatial

requirement, number of size of openings and other factors such as planting landscaping

elements on external features; which will enhance good movement of fresh air and body

cooling. The site zoning are also equally significant and these should be sufficiently

incorporated in the preliminary stage of design process and development stage.

Finally, an air flow in SEMS’ building is seen as a double design development

because of its spatial corridor and open courtyard within the building and right round the

offices and lecture’s room.


REFERENCES

Aronin, J.E. (1953). Architecture and Climate. Reinhold publishing corp., New

York.

Evans, M. (1980). Housing, Climate and comfort. The Architectural press, London.

Givoni, B. (1976). Man, Climate And Architecture Second Edition. Applied Science

Publishers Ltd. London.

Jennins, B.H (1978). The Thermal Environment: Conditioning And Control. Harper

and Row, New York.

Olgyay, V. (1963). Design with Climate- Bioclimatic Approach To Architectural

Regionalism. Princeton University Press, Princeton, New Jersey.

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