Report Air-conditioning System PDF

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Table of ContentsNO CONTENTS PAGE1 INTRODUCTION2 METHODOLOGY3 CALCULATION4 RESULT AND DISCUSSION5 CONCLUSION6 REFERENCES1 INTRODUCTIONThe part five student have been given a task to design a complete air conditioning systems. The design must be accordingly developed with the given guidelines. The ta...

Description

Table of Contents

NO

CONTENTS

1

INTRODUCTION

2

PAGE

METHODOLOGY

3

CALCULATION

4

RESULT AND DISCUSSION

5

CONCLUSION

6

REFERENCES

Page | 1

1.0

INTRODUCTION

The part five student have been given a task to design a complete air conditioning systems. The design must be accordingly developed with the given guidelines. The task must contain the design specification, project report and project presentation. 

To apply the knowledge from the theory to a practical use in designing a complete air conditioning systems



To work effectively in team



To design and propose an air conditioning systems

Air conditioning is needed to achieve human comfort. It can be set to cold or hot temperature. It is a process of removing heat from the interior of an occupied space, to improve the comfort in space. Air conditioning can be used in both domestic and commercial. This process is most commonly used to achieve a more comfortable interior environment, typically for humans or animals. However, air conditioning is also used to cool or dehumidify rooms filled with heat-producing electronic devices, such as computer servers, power amplifiers, and even to display and store artwork. For our project, we have been choosing the Chess Room. It is located at the TAR 2 block of UiTM Bukit Besi Campus. The reason why we choose this room is because the condition inside the room do not bring enough comfort to the persons inside. In addition, during sunrise, the heat is directly via the big windows located at the East. Thus, the condition in the room at this time is quite hot and not comfort compared to other times. Besides, another heat source is the heat from light and heat from electronic devices such as laptop, printer and photocopy machine. Thus, we need to calculate the cooling load in Chess Room that effect the efficiency of air-conditioner so, we can determine how to increase the efficiency in the room for bring enough comfort to the person inside.

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Floor Plan

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2.0

METHODOLOGY 2.1 Method for Calculation

Cooling load estimation (CLTD) The CLTD (cooling load temperature difference) cooling load calculation method was first Introduced in the 1979 ASHRAE Cooling and Heating Load Manual. The CLTD Method is regarded as a reasonably accurate approximation of the total heat gains through a building envelope for the purposes of sizing HVAC equipment. This method is suitable to determine the type of air-conditioning system that can be proposed by A post building, and cooling load can be calculated so that the system could supply comfort cooling to the occupants. Required data for cooling load calculations 

Building location and orientation (Architectural Plans)



Building construction (Architectural Plans)



Outdoor design conditions



Indoor design conditions



Occupancy schedule



Lighting



Equipment schedules



Infiltration / ventilation

cfm =

coolingload 12 x 10 3

Daikin Psychometric Diagram Viewer Daikin offers free of charge software that can display the properties of moist air in changing conditions. Data that included in the software are dry bulb temperature, wet bulb temperature, dew point, relative humidity, enthalpy, density, specific volume and pressure. The information gained is important for the cooling load calculation.

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2.2 Procedure

1.BREAFING BY LECTURER

2. GROUP DISCUSSION

3. PLACE SELECTION

4.MEASUREMENT OF LOCATION

5. FLOOR DRAWING

6. CALCULATION

7. LECTURER FOLLOW UP

8. RESULT AND DISCUSSION

9. DOING REPORT

10. PRESENTATION AND SUBMTTION

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2.3 Assumption of Design Requirement The room area is about 562,874.4 m². Total wall number of the room is four. Next, the zone type is typical Malaysia. No of pax is 5 people. The equipment that installed in the room as the table below : No

Item

Heat transfer

Quantity

1

People

Convect

5

3

Laptop

Radiation

3

4

Printer

Radiation

2

5

Photocopy machine

Radiation

1

6

Lamp

Radiation

2

7

Phone

Radiation

1

8

Door

Convect

1

9

Window

Radiation

4

10

Fan

Radiation

1

12

Wall

Convect

4

13

Chair

Convect

4

14

Table

Convect

4

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2D Floor Plan

Picture 1 : 2D Floor Plan

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3.0

CALCULATION 3.1

BTU/sq.ft

Table 1: Cooling Load Estimation Tables Size :20.06 ft X 10.14 ft = 203.4sq X 9.45 ft = 192197 cu ft Pschrometric Analysis Condition

db 92

%R H 60

gr/lb

Outside Air (AO)

wb

136

5

Room (RM) Difference

75

55

72

203. 41

17

5

64

1

Dew point

Ventilation Peop le sq.ft ac /hr

cfm x

15

cfm/person =

75

x

0.15

cfm/sq.ft

=

30.51

x

32

vol/60

=

32

=

ac - air change

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Descripti on

Area (sq.ft )

Solar Heat Gain Wall N E S W

72.51

Item

x

x x x x

BTU (Table 7)

16

x

x x x x

(Table 4) N E S W

Glass

23.30

x x x x

167

U (Table 9)

BTU/hr

0.48

556.88

(Table 5) x x x x

0.19

Total

(Table 6) x x 0.43 x x

317.9

874.78 Transmission Heat Gain All Glass Wall

158.28

Partitio n Ceiling Floor Infiltrat ion

x

(Table 9) 1.13

x

(Temp Diff) 17

45

x x

0.48

x x

12

203.4

x x

0.22

x x

17

3040.56 5

259.2

724.71

4024.47 Internal Heat Item No. People

5 (Area)

Lights

203.4 No.

Equip ment

7

x

1225

(Type Factor)

(Table 1)

6 Rate d x 0.1 5

(Table 10) 245 Conversion

x

1.25

x

3.4

5186.7

x

245

x

3.4

874.65

Room Sensible Heat Sub Total Safety Factor (10%) TOTAL ROOM SENSIBLE HEAT (RSH) Outside Air BF (Table cfm 12) Outside Air (1)

30.5

x

0.3

x

7286.4 728.64 8014.99 ºF 1.09

x

17

TOTAL EFFECTIVE ROOM SENSIBLE HEAT (ERSH)

169.6 169.6

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Room Latent Heat

(Table 10) 205

People 5 x Equipme x nt Safety Factor (10%) ROOM LATENT HEAT (RLH) cfm gr/lb BF Outside Air 30.51 x 136 x 0.3 (2) EFFECTIVE ROOM LATENT HEAT (ERLH) (1) + EFFECTIVE ROOM LATENT HEAT (ERLH) (2)

Outside Air Heat (cfm) Sensibl 30.51 e Latent 30.51

x

ºF 17

x 64 gr/lb

1025

102.5 1127.5 x

0.68

846.47 1973.97 2143.57

x

(1- 0.3)

x

1.09

395.74

x

(1-0.3)

x

0.68

929.46

TOTAL ROOM SENSIBLE HEAT (RSH)

1325.2 16383

(BTU/hr)

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3.2

CFM =

CFM/sq.ft

RSH 12∗103

16383 CFM =

12∗10

3

* CFM (Diffuse)

∗500

NUMBER REQUIRER DIFFUSER =

682 500

¿ 1.37 ≈ 2

10 FT

5 FT B

C

A

THROW 1= ¿

room length of dimension number of diffuser

20 2 ¿ 10

THROW 2=

room widthof dimension 10 = number of diffuuser 2

¿5

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Length (ft)

FPM

0.1

14.2

10

950

9x19 INCH 0.1 x 10 =0.0 = 171 INCH 100

0.1

11.0

20

800

8X13 0.1 x 20 =0.0 = 104 INCH 100

CFM

Friction Loss, hf (w )

100 0

BC

500

Total Frictio n Loss

Percentage of loss friction

Size Rectangular

Diamete r ducting (ft)

Ductio n sectio n AB

∑ = 0.03

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4.0

RESULT AND DISCUSSION 4.1 BTU/sq.ft and CFM/sq.ft Size of Area 100 to 150 square feet 150 to 250 square feet 250 to 300 square feet 300 to 350 square feet 350 to 400 square feet 400 to 450 square feet 450 to 550 square feet 550 to 700 square feet 700 to 1,000 square feet 1,000 to 1,200 square feet 1,200 to 1,400 square feet 1,400 to 1,500 square feet 1,500 to 2,000 square feet 2,000 to 2,500 square feet

Capacity Needed 5,000 BTUs per square feet 6,000 BTUs per square feet 7,000 BTUs per square feet 8,000 BTUs per square feet 9,000 BTUs per square feet 10,000 BTUs per square feet 12,000 BTUs per square feet 14,000 BTUs per square feet 18,000 BTUs per square feet 21,000 BTUs per square feet 23,000 BTUs per square feet 24,000 BTUs per square feet 30,000 BTUs per square feet 34,000 BTUs per square feet

Based on the area square feet of room is 203.4 square feet. The recommended air conditioner system is 6,000 BTUs per square feet. It is suitable for 150 to 250 square feet building or room.

4.2 System Selection The most type of air conditioning recommended to this room is packaged air conditioning. The application of packaged air conditioner is to cool a large space at the rooms. Reasons we choose this air conditioning because it saving interior space. When the indoor space does not have room for a big air handler, the package unit can go outside. If the room does not have much yard space, and do not want to donate any to an HVAC system, the package unit can go on the roof. Next, ease of maintenance and service. One benefit of packaged air conditioning units is that maintenance and service are often easier when an air conditioning technician can access all of the different parts of the system from one location. Most systems separate the evaporator and condenser coil, so a maintenance technician may need to spend a lot of time to inspect and clean all components. With packaged units, a technician can inspect every area of the AC with ease. Similarly, technicians can often locate repair issues more easily when experience problems with the unit. Lastly, low indoor noise. No indoor component means a quieter room too. If the packaged unit remains in good

Page | 13

condition, it does not make enough noise to disturb people inside. (AccuTemp Heating and Air Conditioning, 2011 ; Griffith Energy Services, INC, 2012 ) This packaged air conditioning is install and attach through the Air Handling Unit (AHU) room via the ducting. In these packaged air conditioning, all the important components of the air conditioners are enclosed in a single casing like window AC. Thus the compressor, cooling coil, air handling unit and the air filter are all housed in a single casing and assembled at the factory location. Depending on the type of the cooling system used in these systems, the packaged air conditioners are divided into two types. First, ones with water cooled condenser and second, the ones with air cooled condensers. Both these systems have been described below: Packaged Air Conditioners with Water Cooled Condenser In these packaged air conditioner, the condenser is cooled by the water. The condenser is of shell and tube type, with refrigerant flowing along the tube side and the cooling water flowing along the shell side. The water has to be supplied continuously in these systems to maintain functioning of the air conditioning system. The shell and tube type of condenser is compact in shape and it is enclosed in a single casing along with the compressor, expansion valve, and the air handling unit including the cooling coil or the evaporator. This whole packaged air conditioning unit externally looks like a box with the control panel located externally. In the packaged units with the water cooled condenser, the compressor is located at the bottom along with the condenser. Above these components the evaporator or the cooling coil is located. The air handling unit (AHU) comprising of the centrifugal blower and the air filter is located above the cooling coil. The centrifugal blower has the capacity to handle large volume of air required for cooling a number of rooms. From the top of the package air conditioners the duct comes out that extends to the various rooms that are to be cooled. (BRIGHT HUB ENGINEERING, 2017)

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4.3 Planning drawing

Picture 2 : 3D Drawing

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5.0

CONCLUSION

Based on the calculation and theory above, the conclusion that can be made is that to apply the knowledge from theory and calculation and practice it in designing a complete air conditioning system. Next, it seems that the room has the higher cooling load in the morning. Thus, we design and proposed the suitable air conditioning system for the place that has been proposed. Lastly, using the packaged air conditioning system is the most efficient ways to supply the comfortable and suitable air for the human’s sakes.

6.0 i.

REFERENCES AccuTemp Heating and Air Conditioning, Benefits of Packaged Air Conditioning Units, http://www.accutempcomfort.com/blog/air-conditioning-service/what-are-the-benefits-ofpackaged-air-conditioning-units/, [3/12/17]

ii.

Griffith Energy Services, INC, Packaged AC Systems Vs. Split AC Systems, https://www.griffithenergyservices.com/article/when-choosing-packaged-ac-systems-vs-splitac-systems, [3/12/17]

iii.

BRIGHT

HUB

ENGINEERING,

Packaged

Air

Conditioner,

http://www.brighthubengineering.com/hvac/61457-packaged-air-conditioners-types-ofpackaged-ac/, [3/12/17]

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