1. 06411 Mini Nucleating Bubble Engine Team Members Steven Nathenson Joseph Pawelski Joaquin Pelaez Andrew Pionessa Brian Thomson Team Coordinator Dr. Walter Team Mentors Dr. Crassidis Dr. Kandlikar Acknowledgements Steve and Rob in the Machine Shop Multidisciplinary Engineering Senior Design

2. Project Overview Project Description –Creation of a mini device that transmits bubble growth into usable motion –Current MEMS devices use piezoelectric membrane to convert bubble nucleation to electric. –The project focuses on a larger device in order to complete the analysis. –Periodic bubble nucleation is produced a modulated power supply putting a current through a coiled filament.

3. Customer Specifications –Keep the design within a 1 foot cube –Maintain a budget of $500 –Dimensions within a mm scale –Benchmark efficiency of engine –Bubble visualization with high speed camera –Develop mathematical models –Run time of at least 20 seconds –Frequency of at least 5 to 10 Hz.

4. Risk Assessment –Engine parts could be too unique and small May result in going over budgetMay result in going over budget May result in lack of timeMay result in lack of time –The engine design may be to similar to current MEMS devices if a piston or piston like design is not utilized –Bubbles may be too small to move the piston a significant amount for testing

5. Gantt Chart

6. AttributeOption 1Option 2Option 3Option 4Option 5Option 6 Engine TypeBuoyant piston Partially Submerged piston Submerged cantilever beam Non-submerged cantilever beam Rotary w/ ndent Rotary w/ Volume change Liquid Type De-ionized water AlcoholOther------------------------- Impact PlateResistant wireProtective plateOther------------------------- Power Supply DC power supply DC batteryAC power supply------------------------- Heating Element Straight wireSquare wireCircular wireConcentric wireMetal plate------------ Control System Stamp controller ASIC chip Other programmable chip ------------------------- Cooling System NoneFluid reservoirHeat exchanger------------------------- Movement Causality Bubble Impact Boiling & Condensation ------------------------------------------ Electrical System Pulse width Modulator (PWM) AC circuit design DC circuit design------------------------- Morphological Chart

7. Concept Feasibility Weighted Average Analysis

8. Detailed Design Material Selection Piston CasingPiston Casing –Boroscilicate Glass (Pyrex) –Stock part at McMaster - Carr –Machining - glass department is able to cut Piston BasePiston Base –Glass Mica Ceramic – high temp –Machining - Mechanical engineering machine shop PistonPiston –Low Density Polyethylene (LDPE) –Less dense than water –Core center to promote floatation –Machining - Mechanical Engineering machine shop ElectrodesElectrodes –Copper Wire - Stock item at McMaster-Carr Heater ElementHeater Element –Option 1 Platinum wire and soldered electrodesPlatinum wire and soldered electrodes –Option 2 Manufactured heating elements provided by Dr. KandlikarManufactured heating elements provided by Dr. Kandlikar

9. Budget $500 –Piston –Casing –Base –Heater –Electrical Controls

10. Theoretical Models Navier Stokes –Parallel Plates with Gravity Upper plate is moving at a constant velocityUpper plate is moving at a constant velocity –Pipe Flow with Gravity

11. Theoretical Models System Models –Factors taken into account –Two model types Based upon geometrical relationshipsBased upon geometrical relationships Based directly off of the Navier-Stokes equationsBased directly off of the Navier-Stokes equations –5 total models Some neglected forces shown to be insignificantSome neglected forces shown to be insignificant Some include all forces of the systemSome include all forces of the system –Verification Model Simplified version of the modelsSimplified version of the models

12. Systems Model 1 –Second order approximation –Negligible forces are removed –Water displacement is known –Water moves proportional to the displacement of the bubble Theoretical Models B1B1 B2B2 B4B4 xpxp xwxw mpmp mwmw B3B3 K1K1 Water Piston Systems Model 2 –First order approximation –Neglects the viscous shear force due to the air on the piston –Water moves proportional to the displacement of the bubble

13. Additional Theoretical Analysis Bubble growth rate –Mikic’s equations –Experimentally determine with high speed camera

14. Additional Theoretical Analysis Heat TransferHeat Transfer –Transient heat conduction –Semi-infinite solid –For 12 ms pulse, 10 V and between 2 and 5 A were applied to the entire circuit –Power = 20 to 50 W x qo”qo” T ∞ = 25 C T s = 400 C

15. Electrical System Requirements Specifications –Supply pulse signal with adjustable amplitude, duty cycle, and frequency –Signal must be output continuously –100, 72, and 60 W signal for 10, 20 and 30 ms pulse –Implement component protection as well as operator protection –Design for small load resistance (~0.5 Ω) –Flexible for different loads

16. Final Electrical Design (a) Single NMOS(b) Single PMOS(c) Combined Current for saturation condition

17. Final Electrical Design Results

18. Testing Experimental Design –High Speed Camera –Scale –A high intensity light Equipment Camera: Photron Ultima APX digital videoCamera: Photron Ultima APX digital video Lens: Nikon AF Micro NIKKOR 105mm 1:2.8 D with optional 2x magnification.Lens: Nikon AF Micro NIKKOR 105mm 1:2.8 D with optional 2x magnification. Light: 600 watt halogen continuous sourceLight: 600 watt halogen continuous source Fan: High CCM 24 voltFan: High CCM 24 volt Scale: Stainless, +.01 mmScale: Stainless, +.01 mm Camera mount: standard x-y mountCamera mount: standard x-y mount Base: optics tableBase: optics table

19. Testing Wave Heater Coil Heater

20. Customer Specifications Keep the design within a 1 foot cubeKeep the design within a 1 foot cube –Completed: The power supply was reduced in size to maintain this size requirement Maintain a budget of $500Maintain a budget of $500 –Used less than $200 Dimensions within a mm scaleDimensions within a mm scale –The inside diameter of ~5.5 mm –The height of the piston is 25.4 mm Benchmark efficiency of engineBenchmark efficiency of engine –The efficiency has been benchmarked at.07% Bubble visualization with high speed cameraBubble visualization with high speed camera –Video has been taken Develop mathematical modelsDevelop mathematical models Run time of at least 20 secondsRun time of at least 20 seconds –Greater than 20 seconds Frequency of at least 5 to 10 Hz.Frequency of at least 5 to 10 Hz. –Approximately 20 Hz.

21. Results Max displacement of 7 mmMax displacement : 5 mm Efficiency:

22. Results