FLUID FLOW AERATION TANKS by Robert Berry Steven Cai Carl Weinstein ENGINEERING PROJECT REPORT Adviser: Prof. Kyle Watson Department of Mechanical Engineering University of Pacific Stockton, California Spring 2011 2 Acknowledgements The design project would not have been possible without the help from University of the Pacific’s finest. Pacific’s technician Adrian Avila was able to assist the team manufacture and machine the majority of the parts required as well as provide a facility and the necessary tools to continuously work on the project until the end. Dr. Camilla Saviz from the Civil Engineering department provided her fluid mechanics expertise that greatly affected the outcome of the project. Dr. Ken Hughes also assisted with the design and verification of the microcontroller circuit used in the vertical tank. Dr. Kyle Watson was the faculty adviser throughout the term of the project and provided much insight and guidance. A very special thanks to Domenick Mondo, Jr. from Tap Plastics in Stockton, California for donating all of the acrylic and other plastics used in the project as well as his expertise on the material 3 FLUID FLOW AERATION TANKS Abstract By Robert Berry Steven Cai Carl Weinstein University of the Pacific Spring 2011 Fluid mechanics is a fundamental engineering course that engineers of several disciplines are required to take. As mechanical engineers, one can undoubtedly expect the need to work with fluids at some point in their careers. With that, the construction of a unique fountain will lead to a better understanding of some concepts such as fluid flow, specific fluid properties, and buoyancy. Incorporated will be concepts and knowledge from various engineering topics such as mechatronics, mechanics, electric circuits, and computer-aided manufacturing. The complete display is comprised of two tanks. A tall, vertical tank will contain a viscous fluid where air bubbles will be injected into it through a series of solenoids controlled by a microcontroller. These bubbles will coordinate to form letters, numbers, and shapes. A flat, horizontal tank will have water continuously flowing through it with air bubbles streaming through it. Magnetic shapes will be inside the tank for users to manipulate to observe its particular streamline properties with the reaction from the air bubbles in the fluid. 4 TABLE OF CONTENTS LIST OF TABLES ……………………………………………………...……. 5 LIST OF FIGURES ………………………………………………………...... 6 1. INTRODUCTION ………………………………………………….... 7 2. CONCEPTUAL DESIGN ………………………………………….... 9 2.1 Horizontal Streamline Tank ……………………………... 9 2.2 Vertical Buoyancy Tank …………………………………. 13 2.2 Display Stand ………………………………...………...... 15 3. DETAILED DESIGN AND ANALYSIS …………………………… 16 3.1 Horizontal Streamline Tank ……………………………… 16 3.1.1 Horizontal Flow Prototype …………………….. 16 3.1.2 Pump Sizing ……………………………….…… 17 3.1.3 Aeration ………………………………….….….. 18 3.1.4 Exit Flow ………………………………….……. 19 3.2 Vertical Buoyancy Tank ……………………………….… 21 3.2.1 Fluid Viscosity Prototype ………………….…... 21 3.2.2 Viscosity ……………………………………..…. 22 3.2.3 Microcontroller Code and Circuit Diagram ..….. 23 3.2.4 Solenoid Air Pressure ……………………….…. 25 4. MANUFACTURING CONSIDERATIONS …………...……………. 26 4.1 Acrylic Tank Construction ………………………..……… 26 4.2 Machining Various Parts …………………………..……... 27 5. TESTING AND EVALUATION OF PERFORMANCE ………..…... 28 5.1 Horizontal Streamline Tank ………….…………………... 28 5.1.1 Flow Rate Test ……………………….………… 28 5.1.2 Aeration in Horizontal Tank …………………… 29 5.2 Vertical Buoyancy Tank …………………….…………… 31 6. CONCLUSIONS …………………………….……………………….. 35 7. RECOMMENDATIONS FOR FUTURE WORK ….......................... 36 5 REFERENCES ………………………………….……………………………. 38 APPENDICES ……………………………………………………………….. 39 A. Final Design Drawings ………………………………….……...… A-1 B. Detailed Analysis ……………………………………….….…...... B-1 B.1 Horizontal Streamline Tank ……………………………... B.1.1 Horizontal Flow Prototype …………………….. B-1.1 B.1.2 Aeration Prototype …………………………...... B-1.2 B.1.3 Pump Sizing …………………………………… B-1.3 B.1.4 Exit Flow Analysis ……………………………. B-1.4 B.2 Vertical Buoyancy Tank …………………………………. B.2.1 Buoyancy Prototype …………………………… B-2.1 B.2.2 Viscosity Testing ………………………………. B-2.2 B.2.3 Solenoid Pressure Analysis ……………………. B-2.3 C. Microcontroller Code …………………...………………………... C-1 D. Gantt Chart …………………………………………….………..... D-1 E. Budget Sheet ……………………………………………………... E-1 6 LIST OF TABLES 1. Results from Pump Calculations …………………………………………….… 18 2. Viscosity Calculations …………………………………………………………. 22 7 LIST OF FIGURES 1. Fluid Flow Aeration Tank ……………………………………………… 9 2. Horizontal Tank Design …...…………………………………………… 9 3. Entry Endcap Baffles System ...………………………………..…….… 11 4. Vertical Buoyancy ……………………………………………...…….… 13 5. The Display Stand …………………………………………….…..….… 15 6. Horizontal Flow Prototype ...……………………………...………….… 16 7. Pump Design ……………....……………………………...………….… 17 8. Aeration ………………...……………………………………….……… 19 9. Modified Horizontal Exit ……………………………………….……… 20 10. Vertical Tank Prototype …..…………………………………….……… 21 11. Viscometer Test …………………..…………………………….……… 22 12. Solenoid Pseudo-code ………………………………………….……… 24 13. Tank Gluing Procedures …………………………….…………….…… 26 14. Milling on Bridgeport ………………………..………………………… 27 15. ESPRIT Tool Path and CNC Machining ………….…………………… 27 16. Modified Entry Manifold ………………………………………………. 28 17. Modified Exit Endcap and Exit Port ……………...……………………. 29 18. Drain Modification ……………..………………………………………. 30 19. Modified Drain Pipe ……………………………………………………. 30 20. Unaligned Bubble Rows …………….…………………………………. 33 21. Bubble Pattern Sequence …………………………………………….… 34 22. Completed Fluid Flow Aeration Tanks ………………………………… 37 8 1 Introduction The Fluid Flow Aeration Tanks is a novel project that displays multiple engineering concepts and involves many engineering disciplines in the analysis and conception. Specifically, it will display concepts of fluid streamlines and buoyancy through the use of two separate liquid tanks; a horizontal tank and a vertical tank. It is also an interactive learning display as users are able to manipulate the water streamline in the horizontal tank through the use of the magnetic shapes of a square and a circle. The vertical tank will demonstrate the concept of buoyancy in unusual fashion of releasing air bubbles through a series of thirteen solenoids into a viscous fluid. The bubbles can also be coordinated through a microcontroller to display various shapes and patterns. This portion of the tank will incorporate programming techniques and microcontrollers which are becoming much more common in the field of mechanical engineering. Motivations and Objectives - Innovative project that displays multiple disciplines of engineering - Can be used as an interactive outreach or learning tool for Fluid Mechanics - Displays multiple engineering concepts, some interactively: Streamlines, buoyancy - Vertical tank displays pre-determined patterns through controlled bursts of air in fluid - Work with modern microcontrollers and advanced programming techniques to ultimately control pattern display 9 2 Conceptual Design The fluid flow aeration tanks needed a robust design that would allow both a vertical buoyancy tank, and a horizontal streamline tank to be shown interactively at the same time. While displaying them at the same time, it is also important to make the distinction between the two tanks as two separate entities and maintain space for the equipment that Figure 2.1: Fluid Flow is intrinsic with each system (i.e. pump system and Aeration Tanks electronics). A model of the design the cart was based on is displayed in Figure 2.1. To more easily discuss these tanks it will be easier to review them in three separate sections: horizontal streamline tank, vertical buoyancy tank, and the display stand. For any of the subsections in section two please refer to the Final Design Drawing package in Appendix A-1. 2.1 Horizontal Streamline Tank The horizontal tank's purpose is to display streamline characteristics of fluids in a highly interactive and controllable environment. The tank itself was designed to utilize a continuous Figure 2.2: Horizontal Tank Design fluid source, in this case water, which 10 has a controllable flow rate and an even flow across the entire cross-section of the tank as seen in Figure 2.2. In order to view the streamlines the novel idea of introducing small bubbles into the system at a controlled rate would be effective. This method has both the benefit of continuously showing streamlines through bubbles in the water and allowing for an indicator that, unlike most other systems, allows for the continuous use of a single source without the use of small particle filtration systems or die packs. In order to view streamlines some obstructions were designed to be interactively placed in the tank. This brief synopsis makes it clear that in order to relay the design characteristics of the horizontal tank it would be easier to break it down into further subsections: the horizontal tank itself, the pump system connecting to the tank, the end-caps of the tank that act as the entry and exit points for the tank, and the obstructions within the tank. 2.1.1 The Horizontal Tank Design The horizontal tank has an elongated thin rectangular profile of about twelve inches wide, thirty-six inches long with a half inch gap in the center. It was designed to be made out of quarter inch thick acrylic sheets and chemically bonded together as will be further discussed in section four on manufacturing. The tank was designed so as not deform by the water flowing through it while leaving a large enough gap to fit pre-determined shapes in it to act as obstructions. 2.1.2 The Pump System The pump system to the cart did not have an involved design initially. It was determined that a retention tank would be required to act as both a water reservoir for