Turbulence After the Bend Jeffery Aguiar Drew Hayes University of the Pacific CVL-130 Fluid Mechanics Dr. Camilla Saviz

Presentation Topics Purpose Background theory Experimental design Results Analysis Suggested improvements Conclusion

Introduction Constructed 3 water pipes that tested the theory of turbulence after a bend Measured the length of turbulence for each pipe a total of three times Analyzed results & compared with theory Implemented & suggested further improvements of the experiment

Purpose Theory predicts that ~20 diameters away from a 90º bend a turbulent regime is witnessed iff the flow is laminar before the bend After the set length of turbulence the flow then transitions back to laminar

Theory Calculate flow rate using manometer Q = Ko(H/G)1/2 where Ko= Constant H = displaced height in manometer [in] G = 1

Theory (cont’d) Reynolds Number (<2300, laminar) vd Re =  where v = velocity [ft/s]  = viscosity [ft2/s] d = diameter [ft]

Experimental Design Design of a single apparatus Figure 1- Experimental apparatus used to measure turbulent regime

Actual Design Figure 2- Apparatus used to measure turbulent regime before drilling injection points

Procedure Set up the system Check for laminar flow Inject dye Measure turbulent zone length Three for each apparatus & three manometer readings Repeat with varying pipe diameters

Results Figure 3- Plot of the calculated of L/D values versus Reynolds

Results (cont’d) Figure 4- Plot of the calculated of the length of the turbulent regime values as function of pipe diameter

Analysis Agreement with the theory (~20) Direct relationship between l/d values & pipe diameter Accuracy of l/d values (avg. D=1.03,max D=2.33)

Suggested Improvements Problem Solution Wall friction Smooth pipe (e/d) Injection point Longer needle Transition point Larger diam. pipe Air bubbles Air release valve Measured Length Ruler along pipe

Conclusion Observed turbulence after the bend Measured the length of turbulence Confirmed the theory

Now please enjoy our video ! Acknowledgements Dr. Camilla Saviz Adrian Now please enjoy our video !