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2. Team Members  Jeffrey Kung  Richard Sabatini  Steven Ngo  Colton Filthaut 2 Faculty Advisor Jim Mohrfeld Underclassmen Walter Campos Alan Garza Industry Advisor Christopher Keller

3.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 3

4.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 4

5.  To have a working Stirling Engine that will serve as a portable generator capable of producing 2.5 kWh (3.4HP)  To be able to run multiple common household appliances simultaneously 5

6.  Appliances (average): ◦ Refrigerator/Freezer = Start up 1500 Watts  Operating = 500-800 Watts ◦ Toaster Oven = 1200 Watts ◦ Space Heater = 1500 Watts  Lights: Most common are 60 Watt light bulbs  Tools (average): ◦ ½” Drill = 750 Watts ◦ 1” Drill = 1000 Watts ◦ Electric Chain Saw 11”-16” = 1100-1600 Watts ◦ 7-1/4” Circular Saw = 900 Watts 6

7.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 7

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10.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 10

11. 11 FuelDensityPracticalityPriceMax Temperature Propane Gas2.01 g/cm³$2.48 per gallon1800˚ C 5435 Electric Burner (1.4 kW) ~16¢ per kWh800˚ C ~152 Gasoline.75 g/cm³$3.504 per gallon1000˚ C 2423

12. 12 Working Fluid Thermal Conductivity Absolute Viscosity Specific Heat Gas Constant Safety/ Practicality Nitrogen.026 W/m °C 0.018 centipoises1040 J/kgK297 J/kgK 13113 Helium.149 W/m °C0.02 centipoises5188 J/kgK2077 J/kgK 34334 Hydrogen 0.182 W/m °C0.009 centipoises14310 J/kgK4126 J/kgK 4154 1

13.  Melling Cylinder Sleeve ◦ Cast Iron Cylinder ◦ High in Strength ◦ Thermal Conductivity 55 W(m.K) ◦ Would Need to be Bored/Honed 13

14. 14  Displacer Piston ◦ Cummins KT 19 ◦ Forged Aluminum ◦ High in Strength ◦ Density of 0.101 lb/cu. in.  Power Piston ◦ Yamaha Grizzly 660 ◦ Forged Aluminum ◦ High in Strength ◦ Density of 0.101 lb/cu. in.

15. BrandVoltageAmpsTorque Req.PriceTotal Mechman14 Volts240A8.092 lb-ft$350.00 434415 Eco-Tech14 Volts325A9.000 lb-ft$1500.00 453110 DC Power14 Volts250A10.924 lb-ft$590.00 442313 https://www.dcpowerinc.com/http://www.ecoair.com/http://www.mechman.com/ 15

16.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 16

17. Base Engine Requirements (RPM, Power) Engine Calculations (Heat, Dimensions, Pressure, Work) Heat Transfer & Regenerator Calculations Efficiency &Total Work Loss Calculations 17

18.  Variables ◦ Connecting Rod Length (L) ◦ Crankshaft Arm Length (R) ◦ Force on Piston (F) ◦ Mass of Piston (M) ◦ Angular Velocity (ω)  900 rpm required => (ω)= 94.25 rad/s 18 F L R ω M Crank-Slider mechanism Power and Displacer Piston

19. 19  Displacer Piston Diameter: 6.25” (Piston) Connecting Rod Length (L): 5.375” Crankshaft Arm Length (R): 1.75” (3.5” Stroke) Mass of Piston (M): 25 lbm 1.6:1 Piston to Displacer dia. Ratio  Power Piston Diameter: 4” (Piston) Connecting Rod Length (L): 5.375” Crankshaft Arm Length (R): 1.75” (3.5” Stroke) Mass of Piston (M): 1.561 lbm Regenerator Flywheel

20. 20 Piston Acceleration and Force  Power Piston Acceleration  Power Piston Force  Displacer Piston Acceleration  Displacer Piston Force

21. 21 Required Force

22. 22 Work/ Kinetic Energy(N*M) http://cnx.org/content/m32969/latest / KEY POINTS Work being delivered to the system from 0 to 180 degrees (downward direction) Starting pressure when Θ=0: 221 psi Displacer piston dia: 6.25” Power Piston dia: 4” 20% Mechanical Friction loss RPM=900

23. 23 Force Delivered to Force Required Check and Balance

24. 24 Torque ; ;

25. A D E C A B 25 Torque Related to Kinetic Energy Preferred Method WORK delivered from PRESSURE= 208.333 N*M WORK remaining after FRICTION= 166.664 N*M STORE HALF of the energy to be delivered for UPWARD movement of POWER PISTON (=180 to 360)

26. 26 Flywheel is typically set between.01 to.05 for precision

27. 27 Crankshaft Sn= Endurance Strength=0.50 (UTS) Sn’=Fatigue Endurance Strength Cm= Material Factor= 1.0 Cst=Type of Stress Factor= 1.0 Cr= Reliability Factor= 99%=.81 Cs= Size factor=.88 N= safety Factor= 2

28. 28 http://enginemechanics.tpub.com/14037/css/14037_90.htm Overview Pressure= 2.1 MPA (220 PSI) 20% Energy Loss= 21.7 N*M K.E.=166.7 N*M Storing Half K.E. @ 0 º to 180 º Deliver K.E. @180 º to 360 º= 83.36 N*M Constant Torque= 26.5 N*M

29. 29 Manufacturing

30. 30 Manufacturing Yamaha Grizzly 660 Mazda Miata Rear Drive Hub

31.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 31

32. First Order Design Method Calculate Ideal Adiabatic & Isothermal Conditions. Analyze changes in temperature, pressure & volume in order to get an estimated power output Calculate initial engine parameters ( Swept Volumes, Dead volumes, Change in mass, Stroke Lengths, & rotational speed) Create a finished first order Design Calculation Sheet allowing us to obtain the previous variables. Second Order Design Method Calculate real life conditions & losses (gas pumping/friction losses, heat transfer rate, porosity, mass flow rate of gas, vibrational forces, principle stress, fatigue rate) Design & Calculate regenerator parameters, tubing dimensions, & Fin parameters. Design & Build a calculation sheet allowing us to obtain several arrays of values for each variable in order to find the best engine operating conditions 32

33. 33 Total Net Work(Joules) Power Output(Watts) Total Volume =MAX(Vexp+Vcomp+Vdead) Total Volume = (7065.3 cm^3)

34. 34 We have picked 15 Hz (900RPM) because we can achieve a high enough torque to up-gear our engine ratio 3:1 giving us 2700(RPM) at a high output power of 3010 (watts) Output values from Stirling Program imported into Excel Freq. (Hz.) Power (Watts) Therm. Eff.% Torque (N.m) Pressure (Pascals)

35. 35 Wout= net work done by entire engine Pe*dVe= The change in expansion volume as a function of expansion space pressure Pc*dVc=The change in compression volume as a function of compression space pressure Work in expansion space= 7162.2(Joules) Work in compression space= -6961.4(Joules) Pout= (7162.2)(J)+(-6961.4)(J) *(15Hz)=3010 Watts

36. Tubes Regenerator Fins 36 Reduces heat by maximizing surface area, allowing the outside Air to flow more freely over the tubes Reduces heat by the use of porous material, which catches & conducts the hot air as it flows through steel mesh Thin long blades that consist of a more thermally conductive metal will extend out into the environment dissipating heat through convection by air

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40. 40 Max Hoop Stress Equals= 14,368 psi Allowable Yield Stress for ChromMolly AISI 4140 at 600C is 60,400psi or (417MPa) Max Operating pressure is 376 psi

41.  Regenerator Design- ◦ Reduces heat by a porosity matrix that catches the heat as the helium flows through it ◦ Will store about 60 percent of the heat in the system 41

42. 42 Gasket Material Selection Actual Regenerator Housing The Ideal gasket material we will use A spiral round gasket/ GraphiteFoil mix

43.  As the swept Volume increases by a factor of “x” the # of tubes must also increase by that factor(if you double the volume you double the tubes) 43

44.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 44

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47.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 47

48. Stirling Generator Research Concept & Feasibility Market Research Cost Analysis Project Development Component Selection Intro Design Design Detailed Design & Calculation CAD/CAM Design Components Analysis & Data Results FEA Thermal Analysis FEA Mechanical Analysis Fabrication Mechanical Components Electrical ComponentsWBS 48 100% 61%-99% 31%-60% 100% 1%-30%

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51.  Goals  Prototype Model  Component/Material Selection  Design ◦ Mechanical Design ◦ Thermodynamic Design  Cost Analysis  WBS/Gantt Chart  Risk Matrix 51

52. 52 RiskMatrix

53.  Plan, Plan, Plan ◦ Project management is incredibly crucial ◦ Manufacturing takes longer than projected ◦ Selecting component standards within the industry is key ◦ Start funding early  Public speaking is an acquired skill 53

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55. 55 Cot-mect4276.tech.uh.edu/~stngo3