1. 1 2009-2010 FINAL YEAR PROJECT DEPARTMENT OF MECHANICAL ENGINEERING A.V.C COLLEGE OF ENGINEERING

2. 2 16 TH APRIL 2010 PROJECT PRESENTATION FINAL YEAR PROJECT

3. 3 PROJECT GUIDE : Mr.A.BALAJI, M.E., LECTURER IN MECHANICAL DEPARTMENT A.V.C COLLEGE OF ENGINEERING. PROJECT STUDENTS P.ANANDHAKUMAR (80106114002) G.ARULPRAKASAM (80106114003) G.PUGAZHENDHI (80106114025) M.DHINESH (80106114304)

4. 4 CONTENT INTRODUCTION PROJECT TITLE INTRODUCTION PROBLEMS OBJECTIVES EXPERIMENTAL METHOD TECHNICAL VIEWS METHODOLOGY COMPARISON OF RESULTS APPLICATIONS LITERATURE VIEW PROJECT STATUS CONTENT

5. 5 ANALYSIS OF THERMAL CONDUCTIVITY AND THERMAL STRESS ON ALUMINIUM SILICONCARBIDE COMPOSITES

6. 6 INTRODUCTION Heat transfer plays a important role in the performance of atomic reactors, rockets and jet engines and development work in progress. The post-war era has consequently seen a substantial increase in the interest shown in the thermal properties of materials particularly in determinations of thermal conductivity.. In this work the thermal stress of Aluminium silicon carbide composites was analyzed.Effort was taken to prove the thermal conductivity of adding SiC with Aluminium.

7. 7 The thermal conductivity of materials is defined as the amount of energy conducted through a body of unit area and unit thickness in unit time or heat flow per unit time across unit area when temperature gradient is unity. K = (Q/A) × (dx/dt) Where K – Thermal Conductivity (W/mK) Q – Heat transfer (W) dx/dt – Temperature gradient THERMAL CONDUCTIVITY

8. 8 Thermal conductivity of material is due to flow of free electrons and lattice vibrational waves. Thermal conductivity in case of pure metal is the highest e.g. (Copper 385W/mK, silver 410w/mK﴿ it decreases with increase impurity. Thermal conductivity of a metal varies considerably when it is heat treated or mechanically processed. Thermal conductivity of most metal decreases with the increase in temperature. REGARDING THERMAL CONDUCTIVITY

9. 9 THERMAL STRESS Stress introduced by uniform or non uniform temperature change in a structure or material which is constrained against expansion or contraction.

10. 10 A composite material is a combination of two or more materials having compositional variation and properties distinctively different from those of individual materials of the composite. COMPOSITE MATERIAL

11. 11 PROBLEMS To determine the thermal conductivity of a composite material is experimentally difficult. For a composite material it is difficult to analyze the thermal stress in experimental method. We need experimental results which were already proved.

12. 12 OBJECTIVES To analyze the thermal stress for a composite material-Aluminum silicon carbide To find a methodology to prove the thermal conductivity of a composite material.

13. 13 TRANSFER THE READINGS TO ANALYSIS METHOD REFER THE READINGS FROM EXPERIMENTAL METHOD THERMAL STRESS ANALYSISTRANSIENT STATE ANALYSIS COUPLED STRUCTURAL ANALYSIS GRAPHICAL METHOD USING ANSYS & HYPERMESH PROJECT VIEW

14. 14 EXPERIMENTAL METHOD

15. 15 REFERENCE PROJECT TITLE “DETERMINATION OF THERMAL CONDUCTIVITY OF COMPOSITE MATERIALS” MECHANICAL DEPARTMENT BATCH 2005-2009

16. 16 EXPERIMENTAL SETUP

17. WORKING PROCEDURE This method is a comparative one the unknown thermal conductivity of the material was measured with the reference of materials whose thermal conductivities are known. Such reference materials were Aluminium, Castiron, and Stainless steel. The initial cooling rate of various materials was found out. From the initial cooling rate, material can be identified as higher thermal conductivity and lower thermal conductivity whose thermal conductivities were already known.

18. 18 PROCEDURE Now the graph was drawn between thermal conductivity Vs cooling rate. The thermal comparator embodying cones were placed in a Muffle furnace Controlled at any temperature and left to attain equilibrium. This was indicated by the reading of the differentially connected thermocouples being zero or within a few µv of these values. Meanwhile the samples to be tested were positioned on an insulating blanket and allowed to come into equilibrium with room.

19. 19 PROCEDURE. The initial 70°C and equivalent microvolt readings of differentially connected thermocouples were noted and subsequent readings were taken every 15 seconds after contact had been established. The test was made on materials of higher thermal conductivity to lower thermal conductivity such as Aluminium, Castiron, Stainless steel And also Aluminium Silicon carbide with various proportion of SiC (5%, 10%, 15%).

20. 20 Material: AlSiC (SiC 5%) S.NoTime (sec) Temperature (°C)Avg. Temp (°C) Voltmeter Reading (µv) Trial I Trial II Trial III 1.1568 6767.672752 2.3066 2679 3.456465 64.672626 4.6063 6463.672585 5.75626163622517

21. 21 COOLING RATE Vs THERMAL CONDUCTIVITY AlSiC (SiC 5%) COOLING RATE [  v ] thermal conductivity 151.67W/mK

22. 22 Aluminium silicon carbide is one of the composite materials whose thermal stress is to be analyzed in this project. Basically metal matrix composites can be manufactured in three methods such as Liquid phase processes Solid phase processes Liquid/Solid phase processes SPECIMEN

23. 23 AlSiC COMPOSITE MATERIALS Element % Si6.5 - 7.5 Fe0.2 Cu0.2 Mn0.1 Mg0.2 - 0.45 Zn0.1 Ti0.2 AlRemaining SiC 25

24. 24 ANALYSIS METHOD

25. 25 TECHNICAL VIEWS HYPER MESH For modelling and meshing the material ANSYS Steady state thermal analysis Transient thermal analysis Coupled structural analysis

26. 26 THERMAL ANALYSIS TYPES STEADY STATE THERMAL ANALYSIS TRANSIENT THERMAL ANALYSIS

27. 27 METHODOLOGY To create the shell of the specimen in HYPER MESH. Conversion of model from hyper mesh to ansys. Conduct steady state thermal analysis Apply the method of coupled structural analysis. Then conduct Transient state analysis.

28. 28 HYPER MESH- PROCEDURE Create a profile. Choose element – SHELL 57. Apply the values. Mesh the element. Export the values from hyper mesh to ansys.

29. 29 SHELL57 is a three-dimensional element having in-plane thermal conduction capability.SHELL57 The element has four nodes with a single degree of freedom, temperature, at each node. The conducting shell element is applicable to a three-dimensional, steady-state or transient thermal analysis ELEMENT FOR THERMAL ANALYSIS

30. 30 SHELL57

31. 31 SOLID185 is used for the three-dimensional modeling of solid structures. The element is defined by eight nodes having three degrees of freedom at each node: translations in the nodal x, y, and z directions. ELEMENT FOR STRUCTURAL ANALYSIS

32. 32 SOLID185

33. 33, "A sequentially coupled physics analysis is the combination of analyses from different engineering disciplines which interact to solve a global engineering problem. For convenience,...the solutions and procedures associated with a particular engineering discipline [will be referred to as] a physics analysis. When the input of one physics analysis depends on the results from another analysis, the analyses are coupled." COUPLED STRUCTURAL ANALYSIS

34. 34 Thermal Environment - Create Geometry and Define Thermal Properties 1. Give a Title Utility Menu > File > Change Title... /title, Thermal Stress Example 2.Open preprocessor menu ANSYS Main Menu > Preprocessor /PREP7 3.Define Keypoints Preprocessor > Modeling > Create > Keypoints > In Active CS... K,#,x,y,z COUPLED STRUCTURAL ANALYSIS- PROCEDURE

35. 35 4.Create Lines Preprocessor > Modeling > Create > Lines > Lines > In Active cs 5.Define the Type of Element Preprocessor > Element Type > Add/Edit/Delete...

36. 36 Define Real Constants Preprocessor > Real Constants... > Add... In the 'Real Constants for LINK33' window, enter the following geometric properties: Define Element Material Properties Preprocessor > Material Props > Material Models > Thermal > Conductivity > Isotropic

37. 37 MODELLING IN HYPER MESH SPECIFICATION OF SHELL L=150mm;B=50mm;T=10mm

38. 38 PROPERTY VALUES Young’s modulus 1.15*e 5 N/mm 2 Poisson’s ratio 0.3 Density 2.88*e -9 t/mm 2 Thermal expansion 0.000015mm/ 0 C

39. 39 APPLYING BOUNDARY CONDITIONS

40. 40 Define Mesh Size Preprocessor > Meshing > Size Cntrls > ManualSize > Lines > All Lines... Mesh the frame Preprocessor > Meshing > Mesh > Lines > click 'Pick All' Write Environment The thermal environment (the geometry and thermal properties) is now fully described and can be written to memory to be used at a later time

41. 41 Preprocessor > Physics > Environment > Write In the window that appears, enter the TITLE Thermal and click OK. Clear Environment Preprocessor > Physics > Environment > Clear > OK

42. 42 Structural Environment - Define Physical Properties Since the geometry of the problem has already been defined in the previous steps, all that is required is to detail the structural variables. Switch Element Type Preprocessor > Element Type > Switch Elem Type Choose Thermal to Struc from the srcoll down list.

43. 43 Define Element Material Properties Preprocessor > Material Props > Material Models > Structural > Linear > Elastic > Isotropic The properties are from mat website density-2.88*10^-9 t/mm^2 E=115 Gpa

44. 44 1.Write Environment The structural environment is now fully described. Preprocessor > Physics > Environment > Write In the window that appears, enter the TITLE Struct Solution Phase: Assigning Loads and Solving Define Analysis Type Solution > Analysis Type > New Analysis > Static ANTYPE,0 Read in the Thermal Environment Solution > Physics > Environment > Read Choose thermal and click OK.

45. 45 Apply Constraints Solution > Define Loads > Apply > Thermal > Temperature > On Keypoints Solve the System Solution > Solve > Current LS SOLVE Close the Solution Menu Main Menu > Finish

46. 46 Read in the Structural Environment Solution > Physics > Environment > Read Choose struct and click OK. Apply Constraints Solution > Define Loads > Apply > Structural > Displacement > On Keypoints Include Thermal Effects Solution > Define Loads > Apply > Structural > Temperature > From Therm Analy

47. 47 Define Reference Temperature Preprocessor > Loads > Define Loads > Settings > Reference Temp 1.Solve the System Solution > Solve > Current LS SOLVE

48. 48 COUPLED STRUCTURAL ANALYSIS -NODAL SOLUTION STRESS

49. 49 MAXIMUM TEMPERATURE DISTRIBUTION

50. 50 TRANSIENT STATE ANALYSIS

51. 51 COMPARISON OF RESULTS S.NOTIME IN SEXPERIMENTAL METHOD TEMPERATRE (°C) ANALYSIS METHOD TEMPERATURE (°C) 11567.6768.01 2306666.8 34564.6764.8 46063.6764.01 THE THERMAL CONDUCTIVITY AT 151.67W/mK.

52. 52 It was found that the temperature readings from experimental method and the temperature readings from analysis method are same at thermal conductivity 151.67 W/mK. Thus the thermal conductivity was proved that 151.67W/mK for aluminium siliconcarbide composites A technique has been proposed using analysis method to prove the thermal conductivity of a composite material whose thermal conductivity is unknown. CONCLUSIONS

53. 53 CONCLUSIONS The thermal stress of AlSiC was analyzed an the maximum stress value obtained was 0.02539 N/mm 2. The thermal conductivity and thermal stress can be analyzed at unsteady state condition also.

54. 54 APPLICATIONS It can be used to evaluate performance of atomic reactors, jet engines, rockets. It can be applicable to check the thermal conductivity of a composite material. It is used to calculate the thermal stability of a composite material. AlSiC is used for both structural and electronic applications.

55. 55 LITERATURE VIEW Mr.R.W.POWELL,D.Sc,Ph.D National Physical Laboratory,Teddington. MAT WEBSITE for material properties. ANSYS TUTORIAL ANSYS EUROPE Ltd

56. 56 FUTURE SCOPE OF THE PROJECT This project can be used to find out the thermal conductivity of various materials. This can be used to determine the thickness and bonding resistance. This method can also be used for the identification of materials. It will plays a vital role in thermal fields.

57. 57 TIME PERIOD PROJECT WORK DECEMBER 2009 COLLECTION OF DETAILS JANUARY 2010 STEADY STATE ANALSIS & COUPLED STRUCTURAL ANALYSIS FEBRUARY 2010 TRANSIENT THERMAL ANALYSIS MARCH 2010 DOCUMENTATION

58. 58 TIME CHART

59. 59 COST ESTIMATION DOCCUMENTATION Rs 1000

60. 60 PROJECT PLACE A.V.C COLLEGE OF ENGINEERING

61. 61

62. 62 ?

63. 63 THERMAL COMPARATOR

64. 64 The Wedemkann and Franz law, regarding thermal and electrical conductivities of a material, states as follows The ratio of thermal and electrical conductivities is the same for all metal at the same temperature, and that the ratio is directly proportional to the absolute temperature of the metal. Mathematically (K/σ) α T )or) (K /σ) T=C Where K= Thermal conductivity of metal at temperature T﴾k﴿, Σ = Electrical conductivity of metal at temperature T﴾k﴿, c = Constant referred as Lorenz number c = 2.45×10-8 WΩ/k² T = Temperature in k

65. 65 EXPERIMENTAL SETUP

66. 66 WORKING PROCEDURE This method is a comparative one the unknown thermal conductivity of the material was measured with the reference of materials whose thermal conductivities are known. Such reference materials were Aluminium, Castiron, and Stainless steel. The initial cooling rate of various materials was found out. From the initial cooling rate, material can be identified as higher thermal conductivity and lower thermal conductivity whose thermal conductivities were already known.

67. 67 THERMAL DISTRIBUTION

68. 68 PHOTOGRAPHS

69. 69