Analysis of geometrical relationships and friction losses in small-diameter lay-flat polyethylene pipes

AbstractThe use of lay-flat polyethylene pipes to irrigate horticultural crops has been receiving widespread attention in the last decade, due to the significant improvements in their hydraulic performance, their potentially high application efficiency, and their limited installation costs. However, even if hydraulic design procedures for conventional microirrigation systems are fairly well established, there is still the need to know how different pipe-wall thicknesses of lay-flat pipes can affect the pipe geometry under different operating pressures as well as the related consequences on friction losses. This paper, after comparing two different procedures (caliper and photographic) to assess the geometry of lay-flat polyethylene pipes under different operating pressures, analyzes the friction losses per unit of pipe length, J, in order to identify and to assess a procedure for their evaluation. Hydrostatic tests, initially carried out on pipes with wall thicknesses of 6, 8, and 10 thousandth of an inch...

[1]  Giuseppe Provenzano,et al.  Assessing Hydrus‐2D to Simulate Soil Water Content (SWC) and Salt Accumulation Under an SDI System: Application to a Potato Crop in a Semi‐Arid Area of Central Tunisia , 2015 .

[2]  Leonor Rodríguez-Sinobas,et al.  Determining Minor Head Losses in Drip Irrigation Laterals. I: Methodology , 2002 .

[3]  Gerard Arbat,et al.  Monitoring soil water status for micro-irrigation management versus modelling approach , 2008 .

[4]  Giuseppe Provenzano,et al.  Soil and irrigation sustainability practices , 2013 .

[5]  Guillermo Palau Salvador,et al.  New Computational Fluid Dynamic Procedure to Estimate Friction and Local Losses in Coextruded Drip Laterals , 2007 .

[6]  Joseph B. Franzini,et al.  Fluid Mechanics with Engineering Applications. 6th Ed. By R. L.DAUGHERTY and J. B. FRANZINI. McGraw-Hill. 1965. 574 pp. $9.95 or 80s. Fluid Dynamics. By J. W. DAILY and D. R. F. HARLEMAN. Addison Wesley. 1966. 454 pp. $12.50 or 94s. , 1967, Journal of Fluid Mechanics.

[7]  Giuseppe Provenzano,et al.  Assessing a Local Losses Evaluation Procedure for Low-Pressure Lay-Flat Drip Laterals , 2014 .

[8]  Mario Minacapilli,et al.  Combined use of eddy covariance and sap flow techniques for partition of ET fluxes and water stress assessment in an irrigated olive orchard , 2013 .

[9]  L. Prandtl,et al.  The Mechanics of Viscous Fluids , 1935 .

[10]  Helmi M. Hathoot,et al.  Analysis and Design of Trickle‐Irrigation Laterals , 1993 .

[11]  Mario Minacapilli,et al.  Comparison of SWAP and FAO Agro-Hydrological Models to Schedule Irrigation of Wine Grapes , 2012 .

[12]  J. A. Frizzone,et al.  Method for determining friction head loss along elastic pipes , 2014, Irrigation Science.

[13]  D. Legates,et al.  Evaluating the use of “goodness‐of‐fit” Measures in hydrologic and hydroclimatic model validation , 1999 .

[14]  Giuseppe Provenzano,et al.  Analytical Approach Determining the Optimal Length of Paired Drip Laterals in Uniformly Sloped Fields , 2015 .

[15]  Giuseppe Provenzano,et al.  Experimental Analysis of Local Pressure Losses for Microirrigation Laterals , 2004 .

[16]  Vito Ferro,et al.  Evaluating Pressure Losses in Drip-Irrigation Lines , 1997 .

[17]  Mohammad N. Elnesr,et al.  Field Assessment of Friction Head Loss and Friction Correction Factor Equations , 2012 .

[18]  Giuseppe Provenzano,et al.  Simplified Procedure to Evaluate Head Losses in Drip Irrigation Laterals , 2005 .

[19]  R. D. von Bernuth,et al.  Friction Factors for Small Diameter Plastic Pipes , 1989 .

[20]  T. Kármán,et al.  Turbulence and Skin Friction , 1934 .

[21]  Gary P. Merkley,et al.  Experimental Determination of the Hydraulic Properties of Low-Pressure, Lay-Flat Drip Irrigation Systems , 2011 .

[22]  Allan S. Humpherys,et al.  Hydraulic and Geometrical Relationships of Lay-Flat Irrigation Tubing , 1964 .

[23]  Vito Ferro,et al.  Experimental study on flow-resistance law for small-diameter plastic pipes , 1995 .