Greenheck Fan QEM, QEP manual Airstream Temperature Variations, Plenum Exit Velocity ft/min

Page 11

System

Considerations

3.System effects for plenum discharges must also be calculated and added to the design pressure. In a properly designed plenum (see Duct System Effect

section), the system effect coefficient (Co) depends on the orientation of the discharge relative to the fan and duct connection (if any). For air plenums with multiple discharges, calculate the system effect by using the highest loss coefficient for all discharges. In this example, the discharges are ducted so the

highest loss will be axial (Co "TTVNFUIBUUIF two discharges will each handle 10,000 cfm.

Plenum Exit Velocity [ft/min]

7PMVNF<GU3NJO>0VUMFU"SFB<GU2>

<GU3NJO> JOYJO<JO2GU2>

<GUNJO>

System Effect

 $oY%FOTJUZ<MCGU3> Y

  &YJU7FMPDJUZ<GUNJO> 2

YY  2

4.Now select a fan size from the catalog data based on the corrected performance. The corrected static

QSFTTVSF PG  JO XH QMVT UIF TZTUFN FGGFDU PG JO XH NFBOT UIF GBO TIPVME CF TFMFDUFE GPS

20,000 cfm at 4.0 in. wg. A size 33 plenum will meet this performance at 1290 frpm using 17.9 bhp. (Note: The bhp does not include drive losses. Consult AMCA Publication 203-90 for help in estimating drive

MPTTFT  #BTFE PO UIF SFRVJSFE GSQN UIF VTFS IBT the option of selecting either model QEM or QEP.

 

 

 

 

 

ELEVATION (FEET ABOVE SEA LEVEL)

 

 

 

 

 

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

11000

12000

13000

 

-50

0.77

0.80

0.83

0.86

0.89

0.93

0.96

1.00

1.03

1.07

1.11

1.15

1.20

1.24

 

-25

0.82

0.85

0.88

0.92

0.95

0.98

1.02

1.06

1.10

1.14

1.18

1.22

1.27

1.32

 

0

0.87

0.90

0.93

0.97

1.00

1.04

1.08

1.12

1.16

1.20

1.25

1.29

1.34

1.39

 

50

0.96

1.00

1.03

1.07

1.11

1.15

1.20

1.24

1.29

1.33

1.38

1.44

1.49

1.54

 

70

1.00

1.04

1.08

1.12

1.16

1.20

1.24

1.29

1.34

1.39

1.44

1.49

1.55

1.60

(°F)

100

1.06

1.10

1.14

1.18

1.22

1.27

1.31

1.36

1.41

1.47

1.52

1.58

1.63

1.69

150

1.15

1.19

1.24

1.28

1.33

1.38

1.43

1.48

1.54

1.60

1.66

1.72

1.78

1.85

TEMPERATURE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

200

1.25

1.29

1.34

1.39

1.44

1.49

1.55

1.61

1.67

1.73

1.79

1.86

1.93

2.00

 

 

250

1.34

1.39

1.44

1.49

1.55

1.61

1.67

1.73

1.79

1.86

1.93

2.00

2.07

2.15

 

300

1.43

1.49

1.54

1.60

1.66

1.72

1.78

1.85

1.92

1.99

2.06

2.14

2.22

2.30

 

350

1.53

1.58

1.64

1.70

1.77

1.83

1.90

1.97

2.04

2.12

2.20

2.28

2.36

2.45

 

400

1.62

1.68

1.74

1.81

1.88

1.95

2.02

2.09

2.17

2.25

2.33

2.42

2.51

2.60

 

450

1.72

1.78

1.85

1.91

1.99

2.06

2.14

2.21

2.30

2.38

2.47

2.56

2.66

2.75

AIRSTREAM

500

1.81

1.88

1.95

2.02

2.09

2.17

2.25

2.34

2.42

2.51

2.60

2.70

2.80

2.90

550

1.91

1.98

2.05

2.13

2.20

2.29

2.37

2.46

2.55

2.64

2.74

2.84

2.95

3.06

 

 

600

2.00

2.07

2.15

2.23

2.31

2.40

2.49

2.58

2.67

2.77

2.88

2.98

3.09

3.21

 

650

2.09

2.17

2.25

2.34

2.42

2.51

2.60

2.70

2.80

2.90

3.01

3.12

3.24

3.36

 

700

2.19

2.27

2.35

2.44

2.53

2.62

2.72

2.82

2.93

3.04

3.15

3.26

3.38

3.51

 

750

2.28

2.37

2.46

2.55

2.64

2.74

2.84

2.94

3.05

3.17

3.28

3.40

3.53

3.66

 

800

2.38

2.47

2.56

2.65

2.75

2.85

2.96

3.07

3.18

3.30

3.42

3.55

3.68

3.81

 

850

2.47

2.56

2.66

2.76

2.86

2.96

3.07

3.19

3.31

3.43

3.55

3.69

3.82

3.96

 

900

2.57

2.66

2.76

2.86

2.97

3.08

3.19

3.31

3.43

3.56

3.69

3.83

3.97

4.12

 

950

2.66

2.76

2.86

2.97

3.08

3.19

3.31

3.43

3.56

3.69

3.83

3.97

4.11

4.27

 

1000

2.75

2.86

2.96

3.07

3.19

3.30

3.43

3.55

3.68

3.82

3.96

4.11

4.26

4.42

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Airstream Temperature Variations

8IFO B GBO JT TFMFDUFE UXP UFNQFSBUVSFT JO UIF airstream should be considered: Start-up and normal PQFSBUJPO 8IJMF UIF IQ SFRVJSFE JT SFEVDFE BU IJHIFS temperatures, the motor must be sized based the lowest temperature that could be present in the airstream (when air density is at its maximum value).

Reconsider the example assuming that the fan was operating at 9,000 ft. elevation with a start-up BJSTUSFBNUFNQFSBUVSFPG¡'BOEBOPSNBMPQFSBUJOH UFNQFSBUVSFPG¡' /PUFUIFOFXOPSNBMPQFSBUJOH conditions require the same density correction factor as 13,000 ft. elevation at 70°F, so the fan selection is still valid.)

'JSTUDBMDVMBUFIQBUUIFTUBSUVQDPOEJUJPO'PS¡' at 9,000 ft. elevation, the air density correction factor (Table 2A) is 1.14. Divide the cataloged bhp by the correction factor.

 ŸCIQBUTUBSUVQ

Now calculate hp during normal operation using the TBNFQSPDFEVSFCVUGPS¡'BUGUFMFWBUJPO

ŸCIQEVSJOHOPSNBMPQFSBUJPO

The motor should be sized based on the larger of these two values. So although the normal operation would POMZSFRVJSFBIQNPUPSUIFGBOTIPVMECFTFMFDUFE with a 20 hp motor based on the higher hp requirement at start-up.

 

 

 

 

ELEVATION (METERS ABOVE SEA LEVEL)

 

 

 

 

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

2750

3000

3500

 

-50

0.76

0.78

0.81

0.83

0.85

0.88

0.91

0.93

0.96

0.99

1.02

1.05

1.08

1.15

 

-25

0.84

0.87

0.90

0.92

0.95

0.98

1.01

1.04

1.07

1.10

1.14

1.17

1.21

1.28

 

0

0.93

0.96

0.99

1.02

1.05

1.08

1.11

1.14

1.18

1.21

1.25

1.29

1.33

1.41

 

21

1.00

1.03

1.06

1.09

1.13

1.16

1.20

1.23

1.27

1.31

1.35

1.39

1.43

1.52

 

50

1.10

1.13

1.17

1.20

1.24

1.27

1.31

1.35

1.39

1.44

1.48

1.52

1.57

1.67

(°C)

75

1.18

1.22

1.26

1.29

1.33

1.37

1.41

1.46

1.50

1.55

1.59

1.64

1.69

1.80

100

1.27

1.31

1.35

1.39

1.43

1.47

1.52

1.56

1.61

1.66

1.71

1.76

1.81

1.92

TEMPERATURE

125

1.35

1.39

1.44

1.48

1.52

1.57

1.62

1.67

1.72

1.77

1.82

1.88

1.93

2.05

 

 

150

1.44

1.48

1.53

1.57

1.62

1.67

1.72

1.77

1.82

1.88

1.94

2.00

2.06

2.18

 

175

1.52

1.57

1.62

1.67

1.72

1.77

1.82

1.88

1.93

1.99

2.05

2.11

2.18

2.31

 

200

1.61

1.66

1.71

1.76

1.81

1.87

1.92

1.98

2.04

2.10

2.17

2.23

2.30

2.44

 

225

1.69

1.74

1.80

1.85

1.91

1.96

2.02

2.09

2.15

2.21

2.28

2.35

2.42

2.57

 

250

1.78

1.83

1.89

1.94

2.00

2.06

2.13

2.19

2.26

2.32

2.39

2.47

2.54

2.70

AIRSTREAM

275

1.86

1.92

1.98

2.04

2.10

2.16

2.23

2.29

2.36

2.44

2.51

2.58

2.66

2.83

400

2.29

2.36

2.43

2.50

2.58

2.65

2.73

2.82

2.90

2.99

3.08

3.17

3.27

3.47

 

300

1.95

2.01

2.07

2.13

2.19

2.26

2.33

2.40

2.47

2.55

2.62

2.70

2.78

2.96

 

325

2.03

2.09

2.16

2.22

2.29

2.36

2.43

2.50

2.58

2.66

2.74

2.82

2.91

3.08

 

350

2.12

2.18

2.25

2.31

2.38

2.46

2.53

2.61

2.69

2.77

2.85

2.94

3.03

3.21

 

375

2.20

2.27

2.34

2.41

2.48

2.56

2.63

2.71

2.79

2.88

2.97

3.06

3.15

3.34

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

425

2.37

2.44

2.52

2.59

2.67

2.75

2.84

2.92

3.01

3.10

3.20

3.29

3.39

3.60

 

450

2.46

2.53

2.61

2.69

2.77

2.85

2.94

3.03

3.12

3.21

3.31

3.41

3.51

3.73

 

475

2.54

2.62

2.70

2.78

2.86

2.95

3.04

3.13

3.23

3.32

3.42

3.53

3.63

3.86

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

500

2.63

2.71

2.79

2.87

2.96

3.05

3.14

3.24

3.33

3.43

3.54

3.65

3.76

3.99

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

550

2.80

2.88

2.97

3.06

3.15

3.25

3.34

3.44

3.55

3.66

3.77

3.88

4.00

4.24

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5"#-&# %FOTJUZ$PSSFDUJPO'BDUPST

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11

Page 10 Page 12
Image 11
Page 10 Page 12
Contents Plenum Fans QEM arrangement 9 belt drive Quiet & Efficient Plenum FansAdvantages of the QEM vs. QEP Plenum Model Number CodeSound Performance Performance Comparison Vs -Blade WheelsAdvantages of 12-Blade Wheels Air PerformanceQEM Arrangement Motor on Right QEP Arrangement Standard Construction FeaturesStandard Construction and Features Optional Construction Optional Construction & Accessories Arrangements Available Motor on Frame Positions Left Top RightQEM Arrangement 9 Horizontal, Motor on Frame Side Sizes QEM Arrangement 4 Horizontal, Direct Drive SizesEffects of Air Density System ConsiderationsAir Plenum Design Guidelines Duct System EffectPlenum Exit Velocity ft/min Airstream Temperature Variations100 Direct Drive Selections1770 RPM 60 Hz Plenum Size Plenum Size Plenum Size 2146 2328 4000 1923  2076 2264  QEP Class Maximum rpm Maximum rpm  3900Maximum rpm 2786 RPM #1 3600 1730 1726 19491478 QEP Class Maximum rpmMaximum rpm 2668 3735 35041428 QEP Class Maximum rpm  3409Maximum rpm 2327 RPM #11041 QEP Class Maximum rpm Maximum rpm 2190 3065 28241389 QEP Class Maximum rpm 2744Maximum rpm 1960 108710000 1801 1006 QEP Class Maximum rpm  2382Maximum rpm 1701 210710.2 QEP Class Maximum rpm  21442144 1946 2189 1042 908 1016 1116 12.0 1208 QEP Class Maximum rpm Maximum rpm  1949Maximum rpm 1392 14000 1688 78820000 1970 772 QEP Class Maximum rpm Maximum rpm  1720Maximum rpm 1229 RPM #1 18000 1773 717 822 916 11.7 1001  1083 822 12.4 899 17.4 QEP Class Maximum rpm 949 Maximum rpm 1560 RPM #1 2600033000 2186 684 10.2 761 16.0 829 22.3 892 29.0 QEP Class Maximum rpm 8601215 RPM #1 30000 1988 638  718 790  919 980 38.963.4 1028 72.6 1072 QEP Class Maximum rpm 780903 1007 42000 2296   713 773 829 882  9322007    706   806  QEP Class Maximum rpm 704 9181035 RPM #1 40000 1784 484 10.6  618   730112 883 127 70000 QEP Class Maximum rpm 637 8302369    33.0 642 730 770 8083766 727 72.0 762 93.0 796  827 QEP Class Maximum rpm   692 688 724  790 131 821   879  906 2182339 439 31.1 484 QEP Class Maximum rpm  683 860RPM #1 90000 2216 421 28.0 468     617 116  136 683QEP Arrangement 1 Horizontal, Motor off Frame DimensionsQEM Arrangement 4 Horizontal, Direct Drive QEP Arrangement 1 Vertical, Motor on Frame, Mounted on Side QEP Arrangement 3 Horizontal, Motor off Frame QEP Arrangement 3 Vertical, Motor on Frame, Mounted on Side Quiet dependable operation Design and Selection Support
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