Hi everyone, I have to calculate the critical speed of a vertical shaft. I have been looking on internet how to calculate, and I have found that this critical speed is based on the type of the supports of the shaft. The type of supports determine the deflection of the shaft (δ) and for this reason a fixed-fixed shaft has a higher critical speed than a supported-supported shaft. If it is correct, how can I determine the critical speed of a vertical shaft? Knowing that the deflection of the vertical shaft is lower than the horizontal one, I suppose that the critical speed is going to be higher. Am I correct?