City College of New York School of Engineering Mechanical Engineering Department

ME 54700-Environmental Control

Fall-2010

Subject : Design for a heating and cooling system of a building Instructor : Jorge E. González, Ph.D.NOAA CREST Professor of

Mechanical Engineering Student : Mehmet Bariskan

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Requirement

Design for a heating and cooling system of a building consisting of a restaurant, lounge, and a kitchen for maximum capacity of 100 people. The restaurant is to be located in the New York/New Jersey area and the HVAC design should consider high energy efficient approaches. Building data is as follows;

Building size: 80 ft x 60 ft x 12 ft. Windows are located in the south, north and east sides; with sizes corresponding to wall

area percentages equal to 25%, 10%, and 10%. Windows should be double glazing, low emissivity. Overhangs can be used to reduce cooling loads.

Walls and roofs should use high R values corresponding to minimums of 20 and 36 hrft2- ºF/Btu, respectively.

Lighting intensity is equivalent to 10W/m2. Equipment includes a large gas stove, a large refrigerator, several TV screens spread

across the room, and three computers. Infiltration should be set to a high value equal to 1.5 changes per hour to maintain good

levels of air quality. Provide the following in your solution;

Set a schedule for use of the building. Report infiltration rates, design cooling and heating loads based on daily profile. Define ventilation rates. Refer to ASHRAE Standards for specific application. Design air distribution system. Prefer method is exposed round system. Specify duct

diameters, distance, and exhaust systems. Sizing and recommended HVAC components; V/C system, air handling unit, cooling &

heating coils. Specify vendors of each component and model numbers. Provide schematic of the design. Provide cost estimate of the HVAC system.

Report; Write a concise report that describes the design, and includes the requirements above.

Include a cover page in the report. Reports should not exceed 20 pages total, and are due Friday December 17, 2010, at 5:00 PM EST. Reference: 1. 2007 American Society of Heating, Refrigeration and Air Conditioning (ASHRAE), Applications Handbook.

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Schedule for use of the building

8 am to 8 pm (12 hours /day- Lights on 12 hours to), 100 people max. capacity (100 people an

hour)

80 ft x 60 ft x 12 ft

Total;

Area East (ft2) North ( West ( South ( Wall 648 864 688 720

Window 72 96 0 240

Door 0 0 32 0

Length

Window 2x(9+8)=34 ft 2x(12+8)=40 ft 0 2x(4.5+8)+ 2x(25.5+8)=92ft

Door 0 0 2x(4+8)=24 ft 0

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Kitchen;

Area East (ft2) North ( West ( South ( Wall 336 360 360 360

Window 0 0 0 0

Door 24 0 0 0

Length

Window 0 0 0 0

Door 2*(3+8)=22 ft 0 0 0

Lounge;

Area East (ft2) North ( West ( South ( Wall 336 360 328 324

Window 0 0 0 36

Door 24 0 32 0

Length

Window 0 0 0 2x(4.5+8)=25ft

Door 2*(3+8)=22 ft 0 2*(4+8)=24 ft 0

Restaurant;

Area East (ft2) North ( West ( South ( Wall 648 504 672 396

Window 72 96 0 204

Door 0 0 48 0

Length

Window 2x(9+8)=34 ft 2x(12+8)=40 ft 0 2x(25.5+8)=67ft

Door 0 0 4*(3+8)=44 ft 0

Infiltration rates

Assuming 20 mph (29.5 ft/s),

Δ P=

(inWg)

South North East West

Cp (Figure 7.4) 0.6 -0.2 -0.6 -0.6

0.114 -0.038 -0.114 -0.114

(Figure 7.6) 0.01 0.01 0.01 0.01

0.12 -0.03 -0.12 -0.12

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Assuming k= 1 (tight) for windows, k=0.22 (tight) for wall, k=40 crack 1/8’’, one door on south,

South North East West

(inWG) 0.12 -0.03 -0.12 -0.12

Q/L (Fig. 7.8) 0.35 -0.1 -0.35 -0.35

L window (ft) 92 40 34 0

Q window 32.2 4 11.9 0 48.1

(Q/A) wall (Fig. 7.11) 0.05 0.02 -0.05 -0.05

A wall 720 864 648 688

Qc wall 36 17.3 32.4 34.4 120.1

(Q/L) door(Fig. 7.9) 0 0 0 4

L door 0 0 0 24

Q door 0 0 0 96 96

Total CFM 264.2

And infiltration due to door opening as a function of traffic rate 100 people per hour.

From Figure (7.10) C=2900 (Single-bank type) Q traffic= 1000 CFM

Q Total Infiltration = 1264 CFM

Design cooling and heating loads based on daily profile.

Design Dry 90 F Summer, Winter 20 F

Windows double glazing with low emissivity ( Table 6.6)

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Restaurant

7

8

Lounge

9

10

Kitchen

11

12

Qtotal = 55493 W = 15.78 Tons

For heating;

Restourant

13

14

Lounge

15

16

Kitchen

17

18

Qcooling = 55493 W = 15.78 Tons

Qheating = 40414 W = 11.49 Tons

Ventilation Rates

The volume of building = 80 x 60 x 12 = 57600 ft3

Infiltration should be set to a high value equal to 1.5 changes per hour

= 57600 x 1.5 = 86400 ft3/h = 1440 CFM.

Cooling and Heating Coil capacities

Total volume = 60 x 80 x 12 = 57600 ft2

Flow Rate =

=

= 1440 CFM

%25 of air supplied from inside 0.25 x 1440 = 360 CFM

%75 of air supplied from outside 0.75 x 1440 = 1080 CFM

Specific volume of air

Mass flow rate going to system, coming from outside, returned from inside

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Cooling Coil capacity;

Heating Coil Capacity;

For summer time;

Duct Design;

Section Length (ft)

V (ft

3/min)

∆P/L Duct Loss in WG

Diameter (in)

Velocity (ft/min)

C Fitting Loss in WG

Total WG

1-2 3 1125 0.25 0.0075 16 806 - - 0.0075

2-3 2 1500 0.25 0.005 18 849 0.23 0.01 0.015

2-33 3 375 0.25 0.0075 10 688 0.22 0.006 0.0135

33 2 375 0.25 0.005 10 688 - - 0.005

4-5 4 1500 0.25 0.01 18 849 - - 0.01

6-7 6 1500 0.25 0.015 18 849 - - 0.015

8-9 14 1500 0.25 0.035 18 849 - - 0.035

9-10 15 100 0.25 0.0375 6 510 1.5 0.024 0.0615

10 2 100 0.25 0.005 6 510 0.22 0.0036 0.0086

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9-11 9 1400 0.25 0.0225 18 793 0.009 0.0004 0.0229

11 2 100 0.25 0.005 6 510 1.5 0.024 0.029

11-12 8 1300 0.25 0.02 18 736 0.007 0.0002 0.0202

12-13 15 100 0.25 0.0375 6 510 1.5 0.024 0.0615

13 2 100 0.25 0.005 6 510 0.22 0.004 0.009

12-14 9 1200 0.25 0.0225 16 860 0.008 0.0004 0.0229

14 2 100 0.25 0.005 6 510 1.7 0.028 0.033

14-15 10 1100 0.25 0.025 16 788 0.008 0.0003 0.0253

15-16 15 1100 0.25 0.0375 16 788 0.22 0.009 0.0465

16 2 100 0.25 0.005 6 510 1.8 0.029 0.034

16-17 15 1000 0.25 0.0375 14 936 0.009 0.0005 0.038

17 2 100 0.25 0.005 6 510 1.4 0.023 0.028

17-18 15 900 0.25 0.0375 14 843 0.01 0.0004 0.0379

18-19 10 900 0.25 0.025 14 843 0.22 0.0097 0.0347

19 2 100 0.25 0.005 6 510 1.4 0.023 0.028

19-20 9 800 0.25 0.0225 14 749 0.011 0.0004 0.0229

20-21 15 100 0.25 0.0375 6 510 1.4 0.023 0.0605

21 2 100 0.25 0.005 6 510 0.22 0.004 0.009

20-22 8 700 0.25 0.02 12 892 0.012 0.0006 0.0206

22 2 100 0.25 0.005 6 510 1.41 0.023 0.028

22-23 9 600 0.25 0.0225 12 764 0.014 0.0005 0.023

23-24 15 100 0.25 0.0375 6 510 1.3 0.021 0.0585

24 2 100 0.25 0.005 6 510 0.22 0.0036 0.0086

23-25 8 500 0.25 0.02 10 917 0.016 0.0008 0.0208

25 2 100 0.25 0.005 6 510 1.2 0.019 0.024

25-26 9 400 0.25 0.0225 9 904 0.02 0.001 0.0235

26-27 15 100 0.25 0.0375 6 510 1.12 0.018 0.0555

27 2 100 0.25 0.005 6 510 0.22 0.0036 0.0086

26-28 8 300 0.25 0.02 8 1146 0.03 0.0025 0.0225

28 2 100 0.25 0.005 6 510 1.1 0.018 0.023

28-29 9 200 0.25 0.0225 7 749 0.05 0.0017 0.0242

29-30 15 200 0.25 0.0375 7 749 0.22 0.008 0.0455

30 2 100 0.25 0.005 6 510 0.98 0.016 0.021

30-31 15 100 0.25 0.0375 6 510 0.1 0.0016 0.0391

31-32 17 100 0.25 0.0425 6 510 0.22 0.0036 0.0461

32 2 100 0.25 0.005 6 510 0.22 0.0036 0.0086

Most pressure loss ;

∆Ppomp=0.035 + 0.0229 + 0.0202 + 0.0229 + 0.0253 + 0.0465 + 0.038 + 0.0379 + 0.0347 + 0.0229 +

0.0206 + 0.023 + 0.0208 + 0.0235 + 0.0225 + 0.0242 + 0.0455 + 0.0391 + 0.0461 + 0.0086

= 0.5802 InWG = 144.5 Pa

Component Selection:

Cooling Coil

Supplier: Carrier (www.commercial.carrier.com)

Model Number: 28BDA412HDC121CR

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Performance Data;

Rows Circuit Type

Pins / in Total Capacity Btuh

Water Temp Drop

Leaving Air DB Temp

Leaving Air WB Temp

Water Pressure Drop (ft WG)

Air Pressure Drop (in WG)

4 Half 12 15275 14.7 59.14 57.37 11.3 0.61

Heating Coil;

Supplier: Carrier (www.commercial.carrier.com)

Model Number: 28BHA214HDB121CR

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Performance Data;

Rows Circuit Type

Pins / in Total Capacity Btuh

Water Temp Drop

Leaving Air DB Temp

Water Pressure Drop (ft WG)

Air Pressure Drop (in WG)

2 Half 14 37215 46.19 108.62 9.16 0.52