MECE251 Fluids Lesson 9 part II Pipe Flow

Objectives 1. Discussion and calculation of “minor losses” R·I·T MECE-251 2

Energy Considerations in Pipe Flow • Major Losses: Friction Factor • Head Loss R·I·T

Calculation of Head Loss • Minor Loss: Loss Coefficient, K • Minor Loss: Equivalent

Figure 8. 23 (p. 439) Flow pattern and pressure distribution for a sharp-edged entrance.

R·I·T (a) Reentrant, KL = 0. 8. (b) sharp-edged, KL = 0. 5. (c)

Figure 8. 26 (p. 440) Loss coefficient for a sudden contraction (Ref. 10). R·I·T

Figure 8. 27 (p. 441) Loss coefficient for a sudden expansion (Ref. 10). R·I·T

Figure 8. 31 (p. 443) Character of the flow in a 90 mitered bend

Approximate friction loss for PVC and CPVC fittings in Equivalent Length in feet of

Next Steps L 9 Task 4 B: Please review the example problems on line.

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MECE-251 Fluids, Lesson 9 (part II): Pipe Flow Minor Losses 1 - Read Text Sections 2 - Solve Chapter Problems 3 & 4 – Lectures, Example, and Review Problems 5 - Solve Case Study 6 - Complete On-line Lesson Quiz R·I·T MECE-251 1

Objectives 1. Discussion and calculation of “minor losses” R·I·T MECE-251 2

Energy Considerations in Pipe Flow • Major Losses: Friction Factor • Head Loss R·I·T MECE-251 3

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Calculation of Head Loss • Minor Loss: Loss Coefficient, K • Minor Loss: Equivalent Length, Le R·I·T MECE-251 5

Figure 8. 23 (p. 439) Flow pattern and pressure distribution for a sharp-edged entrance. R·I·T MECE-251 6

R·I·T (a) Reentrant, KL = 0. 8. (b) sharp-edged, KL = 0. 5. (c) slightly rounded, KL = 0. 2. (d) well-rounded, KL = 0. 04. MECE-251 7

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Figure 8. 26 (p. 440) Loss coefficient for a sudden contraction (Ref. 10). R·I·T MECE-251 9

Figure 8. 27 (p. 441) Loss coefficient for a sudden expansion (Ref. 10). R·I·T MECE-251 10

Figure 8. 31 (p. 443) Character of the flow in a 90 mitered bend and the associated loss coefficient: (a) without guide vanes, (b) with guide vanes. R·I·T MECE-251 11

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Approximate friction loss for PVC and CPVC fittings in Equivalent Length in feet of Straight Pipe for water can be found in the table below: The table can also used for othermoplastic pipes materials with similar design. The values can be used to calculate pressure loss with the Equivalent Pipe Length Method. Fitting Friction Loss Equivalent Length - feet of Straight Pipe (ft) Nominal Pipe Size (inches) 1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 4 6 8 10 12 1. 5 2. 0 2. 5 3. 8 4. 0 5. 7 6. 9 7. 9 12. 0 18. 0 22. 0 26 32 90 o Elbow, standard sharp inside radius 3. 6 4. 5 5. 3 6. 7 7. 5 8. 6 11. 1 13. 1 45 o Elbow 0. 8 1. 1 1. 4 1. 8 2. 1 2. 6 3. 1 4. 0 5. 1 8. 0 10. 6 13. 5 15. 5 Gatevalve 0. 3 0. 4 0. 6 0. 8 1. 0 1. 5 2. 0 3. 0 Tee Flow - Run 1. 0 1. 4 1. 7 2. 3 2. 7 4. 3 5. 1 6. 2 8. 3 12. 5 16. 5 17. 5 20. 0 Tee Flow - Branch 4. 0 5. 0 6. 0 7. 0 8. 0 12. 0 15. 0 16. 0 22. 0 32. 7 49. 0 57. 0 67. 0 Male/Female Adapter 1. 0 1. 5 2. 0 2. 8 3. 5 4. 5 5. 5 6. 5 9. 0 14 90 o Elbow, long sweep radius From: http: //www. engineeringtoolbox. com/pvc-pipes-equivalent-length-fittings-d_801. html R·I·T MECE-251 14

Next Steps L 9 Task 4 B: Please review the example problems on line. L 9 Task 4 C: Then, solve the review problem. L 9 Task 5: L 9 Task 6: Re-form groups and work on your case study. Take the Lesson 9 quiz. Reference: Schaum’s Outline of Thermodynamics for Engineers, Second Edition, M. C. Potter and C. W. Somerton, Mc. Graw Hill Several Images are from Fundamentals of Fluid Mechanics, 5/E by Bruce Munson, Donald Young, and Theodore Okiishi R·I·T MECE-251 15