Transcript Document
CONTENTS 1. 2. 3. 4. 5. 6. 7. 8. 9. Introduction Objective and scopes Project flow Literature review Previous work Contact analysis Result Structural modification Conclusion 1. INTRODUCTION • Contact analysis is normally performed on brake assembly to study the pressure distribution and the contact area. • Significant of contact analysis are to investigate the effect of contact problem to the wear, thermal and squeal. • Only Finite Element Method are able to use to perform contact analysis both static and dynamic conditions. content 2. OBJECTIVE “TO DETERMINE CONTACT PRESSURE DISTRIBUTION AND CONTACT AREA OF A DRUM BRAKE ASSEMBLY USING FINITE ELEMENT METHOD” SCOPES Develop a Finite Element model of drum brake. Validate the Finite Element model against experimental result using modal analysis. Perform contact analysis using a commercial Finite Element (FE) software package. Propose structural modification method in order to determine uniform contact pressure distribution and higher contact area. content 3. PROJECT FLOW SMJ 5912 START SMJ 5924 Generate FE model Run modal analysis START Compare Modal Analysis Result Between Experimental and FE Method Perform Contact Analysis using validated model Error not exceed than 5% Purpose structural modification No Yes FINISH FINISH content 4. LITERATURE REVIEW The FE model validated by using modal analysis Contact pressure at leading shoe are more higher than trailing shoe. Parameters that can influence contact analysis are: Coefficient of friction Material properties Actuation pressure Rotation speed Installation gap Figure : Contact pressure distribution for leading and trailing shoes H-i Kang (2002) content 5. PREVIOUS WORK (PSM 1) Three components of drum brake assembly are generated (Drum, leading shoe and trailing shoe) FE model are validated using the experimental data (Modal analysis) Material properties for the model are listed below DRUM BRAKE SHOE BODY LINING Density (kg/m3) 7673 8762 2638 Young's modulus (GPa) 104 250 3.1 Poisson's ratio 0.3 0.3 0.3 FE model Components Types of element No. of elements No. nodes Drum Linear hexahedral elements (C3D8) 7546 13578 Leading shoe Linear hexahedral elements (C3D8) Linear wedge element type (C3D6) 1023 2776 Trailing shoe Linear hexahedral elements (C3D8) Linear wedge element type (C3D6) 1130 2042 content 6. CONTACT ANALYSIS Surface-to-surface contact interaction The drum surface are set as master surface The lining surface are set as slave surface Figure : Result obtain from FE software CONTACT ANALYSIS 6 Parameters were used to study the influence to contact analysis 1. Test condition 2. Coefficient of friction 3. Actuation pressure 4. Material properties (lining) 5. Material properties (brake shoe body) 6. Installation gap content CONTACT AREA WITH DIFFERENT TEST CONDITION Contact area for different drum condition 100 90 Contact area (%) 80 70 Leading 60 Trailing 50 40 30 20 10 0 Static Dynamic Test condition Contact area 5.5% larger for dynamic test condition for leading shoe Contact area are 27.1% smaller for trailing shoe. CONTACT PRESSURE DISTRIBUTION FOR LEADING SHOE Contact Pressure distribution at rotation = 6rad/sec (Leading) Contact Pressure distribution at static condition (Leading) Contact Pressure (Pa) 6.0E+05 Contact Pressure (Pa) 6.0E+05 5.0E+05 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 5.0E+05 Actuation side 4.0E+05 3.0E+05 0 11 22 32 43 54 Angular Position (o) 2.0E+05 65 75 Lining width 86 1.0E+05 97 Dynamic 0.0E+00 Actuation side 0 11 22 32 43 54 65 Angular position (o) 75 Lining width 86 97 Static Abutment side Abutment side CONTACT PRESSURE DISTRIBUTION FOR TRAILING SHOE Trailing shoe step 2 (2-1) 5.0E+05 4.0E+05 3.0E+05 2.0E+05 Lining width 92 102 2.0E+05 Dynamic 1.0E+05 82 Lining width 102 92 Angular position (o) 72 61 51 41 0.0E+00 Actuation side 82 Angular Position (o) 3.0E+05 72 4.0E+05 61 Actuation side 51 5.0E+05 41 0.0E+00 0 10 20 31 1.0E+05 6.0E+05 0 10 20 31 Contact Pressure (Pa) Contact Pressure distribution at static condition (Leading) Contact Pressure (Pa) 6.0E+05 Static Abutment side Abutment side CONTACT AREA WITH DIFFERENT COEFFICIENT OF FRICTION Contact area with different coefficient of friction 100 90 Contact area (%) 80 70 Leading 60 50 Trailing 40 30 20 10 0 0.20 0.25 0.30 0.35 0.40 Coefficient of Friction The higher value coefficient of friction, the lower contact area. CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT COEFFICIENT OF FRICTION (LEADING) Contact Pressure distribution with different value of coefficient of friction (Leading) 6.0E+05 μ 0.20 Contact Pressure (Pa) 5.0E+05 0.25 0.30 0.35 4.0E+05 0.40 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 Actuation side 20 40 60 Angular position (O) 80 100 Abutment side CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT COEFFICIENT OF FRICTION Contact Pressure distribution with different value of coefficient of friction (TRAILING) (Trailing) 6.0E+05 μ 0.20 5.0E+05 Contact Pressure (Pa) 0.25 0.30 4.0E+05 0.35 0.40 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 Actuation side 20 40 60 Angular position (O) 80 100 Abutment side CONTACT AREA WITH DIFFERENT Contact area with different actuation pressure ACTUATION PRESSURE 100 95 Contact area (%) 90 85 80 Leading 75 Trailing 70 65 60 55 50 2.0 2.5 3.0 3.5 4.0 Actuation Pressure (Mpa) Contact area unchained for both shoes when different actuation pressure are applied. 85.7% for leading and 64.2% for trailing CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT ACTUATION PRESSURE Contact Pressure Distribution with different actuation pressure (Leading) (LEADING) 9.0E+05 Pressure Distribution (Pa) 8.0E+05 2 MPa 2.5MPa 3 MPa 3.5 MPa 4 MPa 7.0E+05 6.0E+05 5.0E+05 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 Actuation side 20 40 60 80 o Angular position ( ) 100 Abutment side CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT ACTUATION PRESSURE (TRAILING) Contact Pressure distribution with different actuation pressure (Trailing) 9.0E+05 Pressure Distribution (Pa) 8.0E+05 7.0E+05 2 MPa 2.5MPa 3 MPa 3.5 MPa 4 MPa 6.0E+05 5.0E+05 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 Actuation side 20 40 60 80 o Angular position ( ) 100 Abutment side CONTACT AREA WITH DIFFERENT MATERIAL PROPERTIES (LINING) Contact area with different modulus of elasticity (lining) 100 95 85 80 Leading 75 70 Trailing 65 60 15% 10% 5% baseline -5% 50 -10% 55 -15% Contact area (%) 90 Variation (%) The actual Elastic properties for lining is 3.10GPa CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT MATERIAL PROPERTIES Contact Pressure distribution with different modulus of elasticity (LEADING) (Leading lining) 6.0E+05 -15% -10% -5% baseline 5% 10% 15% Contact Preessure (Pa) 5.0E+05 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 8 Actuation side 16 24 32 40 48 57 65 Angular position (o) 73 81 89 97 105 Abutment side CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT MATERIAL PROPERTIES (TRAILING) Contact Pressure distribution with different modulus of elasticity (Trailing lining) 6.0E+05 -15% -10% -5% baseline 5% 10% 15% Contact Preessure (Pa) 5.0E+05 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 8 Actuation side 16 24 32 40 48 57 65 73 o Angular position ( ) 81 89 97 105 Abutment side CONTACT AREA WITH DIFFERENT MATERIAL PROPERTIES Contact area with different elastic modulus (BRAKE SHOE BODY) 100 95 Contact area (%) 90 85 80 75 Leading 70 Trailing 65 60 15% 10% 5% baseline -5% -10% 50 -15% 55 Variation (%) The actual Elastic properties for brake shoe body is 250GPa CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT MATERIAL PROPERTIES Contact Pressure distribution with different modulus of elasticity (Leading shoe body) (LEADING) 6.0E+05 Contact Preessure (Pa) 5.0E+05 -15% -10% -5% baseline 5% 10% 15% 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 10 Actuation side 20 31 41 51 61 o Angular position ( ) 72 82 92 Abutment side CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT MATERIAL PROPERTIES Contact Pressure distribution with different modulus of elasticity (TRAILING) (Leading shoe body) 6.0E+05 Contact Preessure (Pa) 5.0E+05 -15% -10% -5% baseline 5% 10% 15% 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 10 Actuation side 20 31 41 51 61 Angular position (o) 72 82 92 102 Abutment side CONTACT AREA WITH DIFFERENT INSTALLATION GAP gap Contact area with different installation 100 95 85 80 Leading 75 Trailing 70 65 60 55 2.0. mm 1.5 mm 1.0 mm 0.5 mm 50 0 mm Contact area (%) 90 Installation gap Highest area for leading shoe at 2mm gap (85.8%) Highest area for trailing at 0.5mm gap (65.0%) CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT Contact Pressure distribution by varying the installation gap INSTALLATION GAP (Leading) (LEADING) 6.0E+05 0.5 mm Contact Pressure (Pa) 5.0E+05 1.0 mm 1.5 mm 2.0 mm 4.0E+05 0 mm 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 Actuation side 20 40 60 80 o Angular position ( ) 100 Abutment side CONTACT PRESSURE DISTRIBUTION WITH DIFFERENT INSTALLATION GAP Contact Pressure distribution with different installation gap (Leading) (TRAILING) 6.0E+05 5.0E+05 0.5 mm Contact Pressure (Pa) 1.0 mm 1.5 mm 4.0E+05 2.0 mm 0 mm 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 Actuation side 20 40 60 80 o Angular position ( ) 100 Abutment side content Overall Results PARAMETER CONTACT AREA CONTACT PRESSURE DISTRIBUTION COEFFICIENT OF FRICTION VARY VARY NO VARY E LINING VARY VARY E BRAKE SHOE BODY VARY VARY INSTALLATION GAP VARY VARY ACTUATION PRESSURE content STRUCTURAL MODIFICATION Structural modification done to “Obtain more uniform pressure distribution by seeking greater contact area and lower pressure” Greater contact area and uniform pressure distribution can reduce the uneven wear and squeal. Structural modification done by changing the current geometry MODEL 1 : Adjust location for leading lining MODEL 2 : Adjust location for trailing lining MODEL 3 : Add more length for both shoe MODEL 4 : Add thickness at shoe rib MODEL 5 : Add thickness at shoe platform STRUCTURAL MODIFICATION (CTD) Current Model Model 1 Model 3 Model 4 Model 2 Model 5 CONTACT AREA Contact area with different model 100 90 Contact area (%) 80 70 60 50 40 30 20 Model 5 Model 4 Model 3 Model 2 Current 0 Model 1 10 Figure :Contact area for different models MODEL SHOE 1 2 3 4 5 LEADING 3.8% 0 -1.1% -5.4% 7.2% TRAILING -7.3% -37% -0.2% -8.3% 1.7% Comparison base on current model MODEL 1 3-1 Trailing shoe Contact Pressure (Pa) 6.0E+05 Leading shoe 6.0E+05 5.0E+05 Trailing 4.0E+05 3.0E+05 2.0E+05 1.0E+05 1.0E+05 Lining width 93 Angular Position (o) 82 2.0E+05 72 3.0E+05 62 4.0E+05 51 Actuation side 10 21 31 41 0 5.0E+05 Abutment side 82 72 Lining width 93 Angular Position (o) 62 Actuation side 51 0 0.0E+00 10 21 31 41 Contact Pressure (Pa) 0.0E+00 Leading Abutment side MODEL 2 Trailing shoe Contact Pressure (Pa) 6.0E+05 Leading shoe 4-1 5.0E+05 4.0E+05 Trailing 3.0E+05 2.0E+05 1.0E+05 0.0E+00 93 83 0.0E+00 0 Actuation side 10 21 31 Lining width Abutment side 41 52 o Angular Position ( ) 62 72 83 93 Abutment side Leading 72 Angular Position (o) 1.0E+05 62 2.0E+05 52 Actuation side 3.0E+05 41 0 4.0E+05 10 21 31 Contact Pressure (Pa) 6.0E+05 5.0E+05 Lining width MODEL 3 Trailing shoe 5-1 Contact Pressure (Pa) 6.0E+05 Leading shoe 5-1 5.0E+05 4.0E+05 Trailing 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0.0E+00 94 84 73 63 52 42 31 21 10 Angular Position (o) Leading 94 Lining width Abutment side 0 Actuation side 84 1.0E+05 73 Angular Position (o) 63 2.0E+05 52 Actuation side 3.0E+05 42 0 4.0E+05 10 21 31 Contact Pressure (Pa) 6.0E+05 5.0E+05 Lining width Abutment side MODEL 4 Trailing shoe Contact Pressure (Pa) Leading Lining width 102 92 82 61 71 o Angular Position ( ) 51 41 10 20 31 Actuation side Abutment side Lining width 102 92 82 71 Angular Position (o) 61 51 41 10 20 31 Actuation side Trailing 0 1.0E+06 9.0E+05 8.0E+05 7.0E+05 6.0E+05 5.0E+05 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 0 Contact Pressure (Pa) 1.0E+06 9.0E+05 8.0E+05 7.0E+05 6.0E+05 5.0E+05 4.0E+05 3.0E+05 2.0E+05 1.0E+05 0.0E+00 Leading Abutment side MODEL 5 Contact Pressure distribution at rotation = 6rad/sec (T) Contact Pressure distribution at rotation = 6rad/sec l 5.0E+05 4.0E+05 4.0E+05 3.0E+05 2.0E+05 1.0E+05 102 94 Lining width Abutment side 102 Lining width 94 86 79 71 Angular Position (o) Trailing 86 Angular Position (o) 0.0E+00 79 1.0E+05 0 8 16 24 31 39 47 55 63 71 Actuation side 2.0E+05 Actuation side 5.0E+05 0.0E+00 3.0E+05 0 8 16 24 31 39 47 55 63 Contact Pressure (Pa) 6.0E+05 Contact Pressure (Pa) 6.0E+05 Abutment side Leading content CONCLUSION 1. Only FE method are able to perform contact analysis both static and dynamic conditions. 2. Maximum contact pressure occurs at the actuation side for leading shoe and at the abutment side for trailing shoe. 3. Parameters that can influence the contact properties are coefficient of friction, material properties, actuation pressure and installation gap. 4. Structural modification can improve the contact area and pressure distribution. THANK YOU