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FEAnalyst

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- TL;DR Summary
- What is the simplified analytical approach to blade containment problem?

Hi,

one of the most interesting experimental tests performed for rotating machinery (such as gas turbines) is blade containment test - if the blade detaches from the hub, it can't break through the cover of the turbine because it could result in catastrophic damage (especially in case of airplanes). Apart from physical experiments, such tests are very often performed with FEA. However, I wonder if there's a way to perform some simplified analytical calculations (and determine whether the blade will be able to break through the cover or not) before proceeding to FEA or in order to confirm the correctness of numerical analysis. What I've found so far is approach based on the kinetic energy of the blade after detachment. The formula I've found in some scientific paper is: $$E_{K}=\frac{1}{2}m (\omega \cdot r)^{2}$$ where: ##m## - blade mass, ##\omega## - angular velocity, ##r## - radius. Is this formula correct for a situation when body suddenly switches from rotational to translation motion? What to do next? And is it possible to account for the deformation of the blade (which is significant in this case)?

Thanks in advance for your help

one of the most interesting experimental tests performed for rotating machinery (such as gas turbines) is blade containment test - if the blade detaches from the hub, it can't break through the cover of the turbine because it could result in catastrophic damage (especially in case of airplanes). Apart from physical experiments, such tests are very often performed with FEA. However, I wonder if there's a way to perform some simplified analytical calculations (and determine whether the blade will be able to break through the cover or not) before proceeding to FEA or in order to confirm the correctness of numerical analysis. What I've found so far is approach based on the kinetic energy of the blade after detachment. The formula I've found in some scientific paper is: $$E_{K}=\frac{1}{2}m (\omega \cdot r)^{2}$$ where: ##m## - blade mass, ##\omega## - angular velocity, ##r## - radius. Is this formula correct for a situation when body suddenly switches from rotational to translation motion? What to do next? And is it possible to account for the deformation of the blade (which is significant in this case)?

Thanks in advance for your help