1. Experimental Determination Of Convection Boiling Curves for Water and Ethylene Glycol in a Rectangular Channel with Localized Heating By Andrew T. ONeill 3-23-05

2. Topics of Discussion Introduction Experimental Apparatus Experimental Procedure Results Conclusion

3. Introduction Background Automotive Application Previous Research Objective Realistic Conditions Experimental Data

4. Experimental Apparatus Flow Loop Test Section Heater Instrumentation

5. Flow Loop

6. Flow Loop Control Pressure Flow Rate Temperature

7. Flow Loop Instrumentation Flow Rate Turbine Flow Meter Temperature 3 TCs

8. Test Section

9. Heater Section

10. Test Section Instrumentation Pressure 0-100psia 4 TCs E-type Embedded in Heater Element

11. Heater Element (Dimensions in mm)

12. Heater Thermocouples 4 TCs 3 Along Surface 1 Pair Surface Temp Heat Flux (Dimensions in mm)

13. Heater Assembly

14. Data Acquisition National Instruments LabView Software PCI-MIO-16E-4 Hardware SCXI Signal Conditioning 1102 Module, 1303 Breakout Box 1124 Module, 1325 Breakout Box

15. Data Acquisition Cont. Measurements Flow Rate Temperature Bulk Fluid Heater Pressure Control Bulk Heating Heater Power

16. Assumptions Steady State Condition 1-D Heat Transfer in Copper Element Stabilized Surface Temp and Heat Flux Inlet Temp Used as Bulk Fluid Temp Fluid Pressure Average of Upstream and Downstream Measurements

17. Experimental Uncertainty Flow Rate / Velocity ±1.9 lpm + 2% of reading ±0.05 m/s + 2% of reading System Pressure ±0.017 atm + 0.86% of reading Bulk Temperature ±1.6°C Heater Temperature ±1.5°C to actual ±0.18°C relative Heat Flux ±0.142 W/cm 2 + 5% of reading

18. Experimental Procedure Loop Filling Cleaning Evacuating Degassing Working Fluid Data Collection

19. Loop Filling Cleaning Acetone Solvent Evacuating Dual Stage Rotary Vane Vacuum Pump -5°C Cold Trap Degassing Pressure Vessel After Filling

20. Data Collection Bulk Conditions Set Pressure Inlet Temperature Flow Rate Systematic Curve Development 1000 Samples/s 250 Samples/update 900 Updates After Heat Flux Change 100 Updates Recorded

21. Data Collection Cont.

22. Inlet Temperature 50ºC70ºC90ºC100ºC110ºC 0.5 m/s1.00atm 1.00atm, 1.41atm, 1.97atm, 2.61atm 1.41atm1.97atm 1.0 m/s1.00atm 1.00atm, 1.41atm, 1.97atm 2.0 m/s1.00atm 1.00atm, 1.41atm, 1.97atm 3.0 m/s1.00atm 4.0 m/s1.00atm Bulk Conditions for Water Mean Velocity

23. Data Collection Cont. Inlet Temperature 58.8ºC78.8ºC98.8ºC108.8ºC118.8ºC128.8ºC 0.5 m/s1.00atm 1.00atm, 1.34atm, 1.82atm, 2.45atm 1.34atm1.82atm2.45atm 1.0 m/s1.00atm 1.00atm, 1.34atm, 1.82atm 2.0 m/s1.00atm 1.00atm, 1.34atm, 1.82atm 3.0 m/s1.00atm 4.0 m/s1.00atm Bulk Conditions for Ethylene Glycol Mean Velocity

24. Water Results Effect of Velocity Effect of Subcooling Due to Bulk Temperature Due to System Pressure Effect of Pressure

25. Effect of Velocity

26. Boiling at 90°C, 1.00atm, and 0.5m/s Boiling at 90°C, 1.00atm, and 1.0m/s

27. Effect of Velocity Boiling at 90°C, 1.00atm, and 2.0m/s Boiling at 90°C, 1.00atm, and3.0m/s

28. Effect of Subcooling

31. Boiling at 90°C, 1.00atm, and 0.5m/s

32. Effect of Subcooling Boiling at 90°C, 1.41atm, and 0.5m/s

33. Effect of Subcooling Boiling at 90°C, 1. 97atm, and 0.5m/s

34. Effect of Subcooling Boiling at 90°C, 2.61atm, and 0.5m/s

35. Effect of Pressure

36. Boiling at 90°C, 1.00atm, and 0.5m/s Boiling at 100°C, 1.41atm, and 0.5m/s

37. Effect of Pressure Boiling at 110°C, 1.97atm, and 0.5m/s Boiling at 120°C, 2.61atm, and 0.5m/s

38. Summary of Water Curves Convergence of Boiling Curves Around 20°C Wall Superheat Independent of: Velocity Inlet Temperature Pressure Photographic Study Varied Boiling Behavior Same Heat Flux and Wall Superheat

39. Ethylene Glycol Results Effect of Velocity Effect of Subcooling Due to Bulk Temperature Due to System Pressure Effect of Pressure

40. Effect of Velocity

41. Boiling of Glycol at 98.8°C, 0.5m/s, and 1.00atm Boiling of Glycol at 98.8°C, 2.0m/s, and 1.00atm

42. Effect of Subcooling

45. Boiling of Glycol at 98.8°C, 0.5m/s, and 1.00atm Boiling of Glycol at 98.8°C, 0.5m/s, and 1.34atm

46. Effect of Subcooling Boiling of Glycol at 98.8°C, 0.5m/s, and 1.80atm Boiling of Glycol at 98.8°C, 0.5m/s, and 2.45atm

47. Effect of Pressure

48. Boiling of Glycol at 98.8°C, 0.5m/s, and 1.00atm Boiling of Glycol at 108.8°C, 0.5m/s, and 1.34atm

49. Effect of Pressure Boiling of Glycol at 118.8°C, 0.5m/s, and 1.80atm Boiling of Glycol at 128.8°C, 0.5m/s, and 2.45atm

50. Summary of Glycol Curves Boiling Heat Transfer Independent of: Velocity Inlet Temperature Dependant on System Pressure Photographic Study Similar Boiling Behavior with Varied Wall Superheat.

51. Comparison of Water to Glycol Similar Response to Velocity Increased Wall Superheat with Boiling Effect of System Pressure Effect of Subcooling Constant System Pressure Constant Inlet Temperature Boiling Behavior at High Subcooling

52. Similar Response to Velocity & Increased Wall Superheat

53. Effect of System Pressure

54. Subcooling at Constant Pressure

55. Subcooling at Constant Inlet Temperature

56. Boiling Behavior at High Subcooling Boiling of Water at 90°C, 2.61atm, 0.5m/s, and 40°C Subcooling Boiling of Glycol at 98.8°C, 2.45atm, 0.5m/s, and 40°C Subcooling

57. Conclusion Experimental Apparatus Successfully Constructed Representative of Engine Cooling System Boiling Curves Developed for Water and Water Ethylene-Glycol Mixture Showed Effects of: Velocity Pressure Subcooling

58. Questions?