1. Graduation Project II Green Cooling

2. Design of Thermoacoustic Refrigerator • Advisor Name:Dr. Emad Elnajjar • Group members • Azeeza Saeed 200321817 • Basma Abu-Baker 200302708 • Haniya Awad 200337204 • Shamma Sultan 200321100

3. Outlines • Introduction • Environmental and Economical Aspects • Design and Manufacturing • Project Budget • Testing and Results • Conclusion and Recommendations

4. Objectives Applying engineering knowledge and sense to design and implement thermoacoustic refrigeration system Building and characterizing this system using systematic design method Gaining a practical experience in: How to purchase, select material, instrumentation, read equipments specifications, and prepare design drawings to be built in the workshop

5. Objectives Training ourselves on creating an entrepreneur opportunities for small business ideas and exploring marketing opportunities and looking for a sponsorship Improving different personal skills and encouraging the team work spirit between all group members Looking for a sponsorship

6. Environmental Aspect Today the earth plant suffering from two serious environmental problems: Global warming Ozone depletion

7. Economical Aspect

8. How It Works?

12. Basic Theory Behind TcR

13. 2nd Law of thermodynamics (Clausius statement). • Sound waves are pressure waves.

14. Assumptions The acoustic medium is frictionless. The sound wave compression and expansion processes are isentropic. The sound wave propagates in horizontal direction. The resonator tube walls are rigid.

15. Governing Equations Coefficient of Performance : Coefficient of performance : Cooling power, KW : Acoustic power, KW : Dimensionless/ Normalized cooling power : Dimensionless/ Normalized acoustic power : Sound velocity, m/s : stack cross sectional area, mm2 : Average pressure, KPa

16. Design and Manufacturing Specify operation, working gas and stack parameters Design Choices: Average Pressure, Frequency, Dynamic Pressure, Working gas, Stack material and Stack geometry Design of the resonator Optimization of the stack Design of the stack Design of heat exchanger Design of acoustic driver

17. Stack • Stack and stack holder shape • Stack material • Stack holder material

18. Stack and Stack Holder Shape circular sticks with holes

19. Stack and Stack Holder Shape cont. Parallel plates with rectangular gaps

20. Stack and Stack Holder Shape cont. Spiral stack with fishing line Parallel plates with finishing line

21. Stack Material • Stack material characteristics: 1. Low thermal conductivity. 2. Heat capacity larger than helium heat capacity. 3. Easy to manufacture and shaped.

22. Stack Material Cont .

23. Stack Holder Material • Stack holder material characteristics: 1. Low thermal conductivity 2. Rigidity

24. Stack final dimensions

25. Stack Holder Dimensions

26. Stack Auto CAD Layout

27. Stack and Stack Holder

28. Resonator • Shape • Material • AutoCAD Drawing

29. Resonator Shape • Length equal to λ/2 or λ/4 • Power losses: • λ/4 resonator will dissipate half of energy dissipated by λ/2 resonator

30. Resonator Shape Cont. • Spherical end to simulate the open end • Buffer to reduce turbulence • Tapered section to reduce turbulence

31. Resonator Material • The tube should stand high pressure • Should be rigid • Made of available metal • Suggested Material: • Aluminum • Advantages: • It is available in our workshop

32. Resonator AutoCAD Layout

33. Resonator

34. Heat Exchangers • Material • Size • Weight • Heat transfer rate

35. H.E. Materials and Dimensions

37. Heat Exchanger AutoCAD Layout` Piped heat exchanger Sinusoidal heat exchanger

38. Acoustic Driver • Loud speaker specifications • Housing of the Acoustic Driver • Housing material and specifications • Electroacoustic Power & Efficiency

39. Acoustic Driver Design The selection of the driver is based on : 1.Compactness 2. Lightweight 3. Low losses 4. Bl-factor

40. Acoustic Driver Design

41. Mathematical Equations • The acoustic output power is : Where: Amplitude of the dynamic pressure Volume velocity amplitude Phase difference

42. AutoCAD drawing for the whole system

43. Project Budget

44. Results and Analysis • What we were expecting and what we end with • Results gained • Analysis

45. Results and Analysis • What we were expecting and what we end with? • Results • Analysis

46. System after manufacturing

47. Expected TcR System

48. Expected TcR System Buffer

49. Expected TcR System Buffer Pressure Gage

50. Expected TcR System Buffer Valve Pressure Gage Valve