A steel rotor disk which is part of a turbine assembly has a uniform thickness of 50mm, an outside diameter of 650mm and an inside diameter of 100mm. If there are 250 blades, each of mass 0.16 kg pitched evenly around the periphery of the disk at an effective radius of 350mm, determine the rotational speed at which the hoop stress on the inner surface reaches the yield stress. You may assume that the blades produce a uniform loading around the periphery of the disk.(adsbygoogle = window.adsbygoogle || []).push({});

For steel, poisson's ratio = 0.29; Density = 7470 kg/m^3 and the yeild stress in simple tension = 355 MN/m^2.

I don't know what equations to use? Is rotational speed = w or T? I don't know where to start with finding a way to solve this question?

Can anybody please guide me through the steps in which i can get this speed? The problem is that this question is one of optional question that we didn't get any lecture notes on, so i don't know where to start :grumpy:

Thanks

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# Homework Help: Rotational Speed

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