Design of a Micro Irrigation System for an Almond Orchard

46 Pages·2011·0.56 MB·English

by  Adam Scheuber

Design of a Micro Irrigation System for an Almond
Orchard

by

Adam Scheuber

BioResource and Agricultural Engineering

California Polytechnic State University

San Luis Obispo

2011
TITLE : Design of a Micro Irrigation System
for an Almond Orchard

AUTHOR : Adam Scheuber

DATE SUBMITTED : May 19, 2011

DR. STUART STYLES ____ ______________________________
SENIOR PROJECT ADVISOR SIGNATURE

______________________________________________
DATE

DR. RICHARD CAVALETTO_ ______________________________
DEPARTMENT HEAD SIGNATURE

______________________________________________
DATE

i
ACKNOWLEDGEMENTS

My sincere thanks goes to Scheuber Farms, for providing me with the opportunity to
design a micro irrigation system for their new almond orchard. Tree crops are a new
venture for their operation and I appreciate the amount of trust that they have chosen to
place in me.

Thank you to all of the professors in the Cal Poly BioResource and Agricultural
Engineering Department, and especially to my advisor, Dr. Stuart Styles, who was always
willing to offer guidance.

I would also like to thank my parents for raising me in a loving home and always
providing me with support and encouragement.
ii
ABSTRACT

The owners of Scheuber Farms, a 1,000 acre row crop farming operation located in
Patterson, California, wish to convert a 15-acre field into an almond orchard. For
irrigating the trees, they would like to use a microsprayer irrigation system. The design I
recommend and describe in this paper utilizes proper hydraulic analysis, and is based on
the ability to supply enough water to match the amount of water required by the orchard
during the peak month of an average year.

All of the major components and parameters of the microsprayer irrigation system were
designed at minimal cost while ensuring that they worked efficiently and properly. These
components and parameters included the emitters and hoses, the manifold pipe size, the
pressure regulator’s settings, the sub-main and mainline sizing, the filter type and sizing,
and the pump sizing.

The goal of the project was to maximize the efficiency of the system while minimizing
the cost. The final estimated cost was approximately $1,900 per acre.

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DISCLAIMER STATEMENT

The university makes it clear that the information forwarded herewith is a project
resulting from a class assignment and has been graded and accepted only as a fulfillment
of a course requirement. Acceptance by the university does not imply technical accuracy
or reliability. Any use of the information in this report is made by the user(s) at his/her
own risk, which may include catastrophic failure of the device or infringement of patent
or copyright laws.

Therefore, the recipient and/or user of the information contained in this report agrees to
indemnify, defend and save harmless the State, its officers, agents and employees from
any and all claims and losses accruing or resulting to any person, firm, or corporation
who may be injured or damaged as a result of the use of this report.
iv
TABLE OF CONTENTS

SIGNATURE PAGE………………………..……………………………………………..i
ACKNOWLEDGEMENTS................................................................................................ii
ABSTRACT.......................................................................................................................iii
DISCLAIMER STATEMENT..........................................................................................iv
TABLE OF CONTENTS.....................................................................................................v
LIST OF FIGURES..........................................................................................................vii
LIST OF TABLES...........................................................................................................viii
INTRODUCTION...............................................................................................................1
Background......................................................................................................................1
Objectives........................................................................................................................1
LITERATURE REVIEW....................................................................................................3
Evapotranspiration...........................................................................................................3
Soils..................................................................................................................................3
Salts..................................................................................................................................3
Filters...............................................................................................................................4
Media Filters................................................................................................................4
Tubular Screen Filters..................................................................................................5
Disc Filters...................................................................................................................5
Standards..........................................................................................................................6
PROCEDURES AND METHODS......................................................................................7
Design Procedures...........................................................................................................7
Determination of Peak ET Rate...................................................................................7
Estimate Required Flow Rate per Tree........................................................................7
Estimate the Number of Microsprayers Needed per Tree...........................................8
Select the Proper Microsprayer and Number of Sets...................................................8
Locate the Position of the Manifolds...........................................................................9
Allowable Manifold Change in Pressure...................................................................11
Manifold Sizing.........................................................................................................11
Mainline Sizing..........................................................................................................11
Size and Determine the Pressure Losses Through the Critical Path..........................12
Filtration Required.....................................................................................................12
Total Dynamic Head (TDH) Required of the Pump..................................................13
Pressure Regulation Strategy.....................................................................................13
Air Vent Size and Locations......................................................................................14
Pressure Relief Valve Size and Locations.................................................................15
Manifold to Hose Connection....................................................................................15
Equipment Selection......................................................................................................15
Emitter and Hose Selection........................................................................................15
Filter Selection...........................................................................................................16
Flow Meter Selection.................................................................................................17
Pump Selection..........................................................................................................17
Cost Analysis.................................................................................................................17
RESULTS..........................................................................................................................20
DISCUSSION....................................................................................................................21
v
RECOMMENDATIONS...................................................................................................23
REFERENCES..................................................................................................................24
APPENDIX A....................................................................................................................25
Major Design Experience..............................................................................................26
Establishment of Objectives and Criteria..................................................................26
Synthesis and Analysis..............................................................................................26
Construction, Testing, and Evaluation.......................................................................26
Incorporation of Applicable Engineering Standards..................................................26
Capstone Design Experience.........................................................................................26
Design Parameters and Constraints...............................................................................26
Physical......................................................................................................................26
Economic...................................................................................................................26
Environmental............................................................................................................26
Sustainability..............................................................................................................26
Manufacturability.......................................................................................................27
Health and Safety.......................................................................................................27
Ethical........................................................................................................................27
Social..........................................................................................................................27
Political......................................................................................................................27
Aesthetic....................................................................................................................27
APPENDIX B....................................................................................................................28
APPENDIX C....................................................................................................................36

vi
LIST OF FIGURES

Figure 1: Field Chosen for Microsprayer Design...............................................................1
Figure 2: Parallel Fresno Valves and Casting Sand Media Filters.....................................4
Figure 3: Screen Filter from Fresno Valves and Casting....................................................5
Figure 4: Disc Filter Example.............................................................................................6
Figure 5: Manifold Location and Sizes.............................................................................11
Figure 6: Points of Interest on Sub-main and Mainline....................................................12
Figure 7: Manifold to Hose Connection...........................................................................15
Figure 8: Microsprayer Emitter Locations........................................................................16
Figure 9: Field Layout......................................................................................................37
Figure 10: Attached Detail C............................................................................................37

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LIST OF TABLES

Table 1: Lateral Movement of Water in Various Soils (Burt and Styles 2007).................8
Table 2: Average k Values for Different Bowsmith Nozzles.............................................9
Table 3: Required Pressure (psi) for Various Orifice Sizes................................................9
Table 4: Result of Manifold Placement Program from Burt and Styles (2007)...............10
Table 5: Mainline and Sub-main Sizing...........................................................................12
Table 6: TDH Calculation.................................................................................................13
Table 7: Summary of Major Design Component Costs....................................................20
Table 8: Hose Program Inputs..........................................................................................29
Table 9: Average Pressure of South Field Hose Inlets.....................................................30
Table 10: Inputs for Manifold Sizing North Field............................................................31
Table 11: Hydraulic Computations North Field...............................................................31
Table 12: Pressure Calculations from Computations Table North Field..........................32
Table 13: Inputs for Manifold Sizing South Field............................................................32
Table 14: Hydraulic Computations South Field...............................................................33
Table 15: Pressure Calculations from Computation Table South Field...........................34
Table 16: Summary of Costs.............................................................................................34

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1
INTRODUCTION

Background

For the last twenty-five years, Scheuber Farms has primarily grown row crops. During a
typical year, they will produce corn, alfalfa, oats, wheat, beans, and (occasionally)
tomatoes and melons. These crops are irrigated using either furrow or border strip
irrigation. The farm would like to begin transitioning some of its acreage from these
ground crops to trees. As a component of the transition in terms of the types of crops
grown, the farm management also plans on changing the way the farm is irrigated. The
first field in which they plan to implement these alterations is a lot on which the home of
one of the owners is located. Their current plan is to plant an almond orchard irrigated
using a microsprayer irrigation system. Scheuber Farms has asked for a feasible design
for the irrigation system, one that takes into consideration the important factors of the
shortening supply and cost of water in California. Higher efficiencies and uniformity can
be achieved using such a system, in comparison to furrow or border strip irrigation. The
resulting potentially higher yields would be extremely beneficial to the grower. A
microsprayer irrigation system for Scheuber Farms could decrease the total water used by
the farm and potentially increase its yields. An image of the field is shown in Figure 1
below.

Figure 1: Field Chosen for Microsprayer Design

Objectives

The objectives for this design endeavor are as follows:
1) Design a system capable of maintaining a system distribution uniformity of at least
0.93.
2) Minimize friction loss and design for a maximum water velocity of less than 5 feet per
second.