Table A5. Pressure losses and air flows through Tiger Vac vacuum cleaner 11/13/2007 Round 3

Before (B) or after (A) adding 5 pounds of debris

Total weight of debris transferred into vacuum cleaner (lb)

Venturi meter δP (inches of water)

Static Pressure Measurements made with manometer (inches of water)¹

Absolute pressure measured with pressure transducers (psi)

Time measuring before loading

Time measuring during loading

Air flow (cfm) from venturi meter

Pressure in the hose (inches of water)

Pressure before the filter (inches of water)

Pressure after the final filter (inches of water)

Pressure before the filter (psi) 53748

Pressure after the filter (psi) 55481

B

5.2

8.5

-4.3

-4.6

-5.5

13.848

13.807

5:28

5:30

76.67

A

8.2

-4.3

-4.8

-6.1

13.832

13.748

75.32

B

10.2

9.25

 -4.4

-4.85

-5.8

13.84

13.781

5:35

5:36

79.93

A

 8.7

-4.5

-4.8

-6.2

13.848

 13.756

77.55

B

15.4

9.4

 -4.65

-4.75

-5.8

13.832

13.79

5:40

5:43

80.56

A

 9.1

-4.3

-4.7

-6.1

13.848

 13.781

79.29

B

20.4

9.25

 -4.4

-4.9

-5.8

13.848

13.781

5:47

5:49

79.93

A

 9.05

-4.5

-4.8

-6.15

13.848

 13.773

79.07

B

25.8

9.35

 -4.35

-4.85

-5.95

13.832

13.79

5:54

5:56

80.35

A

 9.4

-4.4

-4.8

-6.3

13.832

 13.773

80.56

B

30.8

9.35

 -4.4

-4.85

-6

13.832

13.781

6:01

6:03

80.35

A

8.6

-4.5

-4.9

-6.3

13.84

13.748

77.11

B

35.8

9.5

 -4.2

-4.9

-5.9

13.832

13.781

6:07

6:10

80.98

A

8.8

-4.45

-4.8

-6.3

13.832

 13.748

77.99

Final

 35.8

9.65

-4.5

-5

-6.05

13.832

13.781

6:15

81.61

¹ Static pressure is the difference in pressure from atmospheric pressure. Negative static pressure indicates that pressure is less than atmospheric pressure.