Question

(2D Yield Criteria, 16 points) The stress distribution of three wind turbine blades were investigated, and found there are thee critical place, A, B and C that are under a fairly high stress state. The 2D principal stresses at these spots are given below. The uni-axial yield strength (Ơy) ofwind turbine material is 100 MPa. Note that this is purely 2D problem. So, just use the 2D yield boundaries in the lecture note to solve this problem (a) Draw the Tresca Yield boundary and Von Mises Yield boundary in principal stress coordinate system by using the given uni-axial yield strength (4 Points) a) Mark the given three stress states on your drawings of (a). (6 Points) b) Determine which blade will be yielded under a given principal stress. Answer this question according to Tresca and Von Mises criteria, respectively (6 Points) 50 0 (MPa) 0 -53 30 0 0 60 (MPa) -40 0 0 70 (MPa)

Answer 1

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