Table A3. Pressure losses and air flows through Tiger Vac vacuum cleaner 11/09/2007 Round 1

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

9.1

 -4.3

-5

-5.45

14.032

14

4:45pm

4:47pm

79.29

A

8.9

-4.45

-4.95

-5.7

14.024

13.984

78.43

B

10.2

8.8

 -4.2

-4.9

-5.65

14.032

13.992

4:55pm

4:57pm

77.99

A

 9.1

-4.4

-4.9

-6

14.032

 13.984

79.29

B

15.2

8.9

 -4.25

-4.8

-5.85

14.04

13.984

5:05pm

5:06pm

78.43

A

 9

-4.3

-4.8

-6.15

14.049

 13.975

78.86

B

20.2

8.9

 -4.2

-4.7

-6

14.049

13.984

5:12pm

5:14pm

78.43

A

9.1

-4.25

-4.75

-6.4

14.04

13.967

79.29

B

25.6

8.9

 -4.3

-4.7

-6.25

14.057

13.967

5:20pm

5:22pm

78.43

A

8.9

-4.4

-5

-6.9

14.032

13.958

78.43

B

30.4

9.1

 -4.4

-5.2

-6

14.032

13.984

5:27pm

5:30pm

79.29

A

9.1

-4.1

-4.7

-6.15

14.04

13.975

79.29

B

35.6

8.75

 -4.1

-4.9

-5.6

14.032

13.984

5:36pm

5:39pm

77.77

A

 9

-4.2

-4.85

-6.2

14.049

 13.967

78.86

Final

35.6

9.25

-4.2

-4.9

-5.75

14.032

 13.984

5:46pm

79.93

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