Assignment 1. Computation of journal bearing

Assignment 1. Computation of journal bearing#

It is possible to use the Reynolds equation to compute de eccentricity and the angle of a journal bearing with fluid film lubrication, given the load \(W\)

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Consider that the journal is displaced in the \(x\) negative direction, so that \(h(\theta) = h_0(1+\varepsilon \cos(\theta))\) where \(\varepsilon=\frac{e}{h_0}\) is the relative eccentricity and \(h_0 = \frac{1}{2}(D_b -D_a)\) is the average gap thickness. The journal is rotating in the positive direction of \(\theta\) (polar coordinates)

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  1. Calculate the pressure distribution \(p(\theta)\) and the value and direction of \(\mathbf{W}\), in the approximation \(\varepsilon \ll 1\).

  2. What happens to the journal if \(\mathbf{W}\) increase a little bit?

  3. Apply the results to this real example, and discuss the value of the maximum load given by the manufactures at this rotational velocity. image.png