Question

finite element method

.'ו Optus 11:56 AM Expert Q&A Finite element method QUESTION 4(20 Marks) - concept and calculation question Consider axial vibration of the circular steel bar shown in Figure 4. The steel bar properties are: p- 7800 kg/m and E-200 GPa. (a)lf the first two natural frequencies are required, sketch the finite element model with clearly labelled element numbers and node numbers, State the element types and the degree of freedoms solved (5 Marks (b)Calculate the stiffiness and mass matrices of cach clements and assemble the global stiffness matrix and mass matrix. (10 Marks) (c)Describe how you would model the problem if 4 natural frequencies are requirod. (5 Marks) A,-1200 mm A,-800 m 300 mnm 400 mm Figure 4. A model of axially loaded bar. Not to scale. Add information

Answer 1

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