tailieunhanh - Friction and Lubrication in Mechanical Design Episode 1 Part 5

Tham khảo tài liệu 'friction and lubrication in mechanical design episode 1 part 5', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 80 Chapter 3 ể ỹ f s c a Total Applied Force x 103 Ibf b Total Applied Force X 103 Ibf Figure a Tangential load sharing between the two contact zones at different applied loads b Distance between the line of action of the resultant frictional resistance and centroid at different applied loads. Traction Distribution and Microslip in Frictional Contacts 81 1 2 3 3 3 2 2 4 5 5 5 3 3 5 6 7 6 4 3 5 7 7 6 4 3 5 6 6 5 3 2 3 4 4 3 1 f2 p2 10000 psi f p2 20000 psi 5 9 10 10 3 7 9 12 13 13 12 9 10 13 14 14 13 10 10 13 14 14 13 9 9 12 13 13 11 8 7 9 10 9 5 4 500 600 700 SOO 900 950 1000 1050 1100 1150 1200 1250 1230 1296 Figure Development of slip regions on a discrete contact area with increasing tangential load. Iterative Procedure The modified linear programming formulation is first implemented with an initial guess for the center of rotation in order to find the discretized traction forces whose directions are predetermined by the preprocessor. Now the residual forces the rectangular components of the sum of the traction forces can be calculated. These residual forces must be equal to zero when the real center of rotation is found since no tangential forces are applied. The residual forces are then used to modify the center of rotation and the process is repeated until the residual forces vanish. The real center of rotation the traction force distribution the microslip region and the angle of rigid body rotation are determined by this iterative procedure as depicted in the flow chart Fig. . 82 Chapter 3 b Rigid Body Movement x1O In. Figure a Joint compliance under same tangential loads before gross slip Case 1 . b Joint compliance under different tangential loads before gross slip Cases 2 and 3