Recent content by Spimon

Homework Statement Determine the load (vertical only) on the three bearings at A, B and C. The shaft is loaded at one end with force F (see attached diagram).Homework Equations Cantilever Beam Deflection Deflection at End = PL^3/(3EI) Deflection at Point X = Px^2/(6EI)*(3l-x)The Attempt at a...

Thanks once again. It's much clearer now. There was a typo (s instead of Hz. Maybe it was meant to be s^-1) in the notes I was given, but that was the least of my problems! All fixed up now. I also found quite a good video to show how it all comes together (well some of it). Being a mechanical...

Ah, makes a little more sense! Thanks so much :D

Hi everyone, Please excuse the somewhat basic question. I'm a mechanical engineering student a little out of my realm! I'm doing some work with signal processing and have been given some data (a series of vibration measurements, out of interest). This includes the following: I'm a little...

Oh, ok. Thanks guys. Maybe it is correct, or at least fundamentally on track - I'm not so worried about the actual numbers as the method. Rude Boy, the final 2 lines of the CLTF are the characteristic equation - just the denominator of the transfer function. To isolate the pole locations, do I...

Homework Statement So this is a bit of a two-part question and I'm unsure which part I'm not doing right (or both!). i) Find the closed loop transfer function of the system shown ii) Design a proportional controller for the system to give a 10% steady state error Any help, hints, suggestions...

Thanks for the replies everyone! I'm certainly doing much more research (this is just a small part of it) and am currently setting up a test rig to try to get what I want happening. This is exactly what I'm trying to do :P Just the appropriate equations are hard to come by. I think my...

So I'm designing an impeller and rather than how to prevent cavitation, I'd like to know how to cause cavitation. I've read up on fluid shear stress and Couette flow, but this all appears to be based on relative velocity dV, of parallel discs, separated by a small distance dX, and fluid of...

Thanks for the link. Unfortunately it's the pump I'm designing (not intended to be a pump, but has a pumpig effect). I may need some experimentation to figure out my pressure drop. Thanks anyway :)

If I understand your problem correctly, you'll need a little more information to find out what you need. Do you have the available pressure or fluid velocity? Dynamic pressure in fluid flow is P = ρ . v^2 / 2 Where: P = Dynamic pressure (Pa) v = Velocity (m/s) ρ = Fluid Density (kg/m3)...

You're spot on. In this scenario (as with many calculators) e simply means 'exponent' or 'times ten to the power of'. It's often shortened (as in Excel) to just XeY meaning 'X times ten to the power of Y' 1.2246e-016 means 1.2246x10^-16 Sure saves writing out 0.00000000000000012246 :)Don't be...

Hi everyone, Hoping someone can point me in the right direction. I'm trying to find (a theoretical approximation of) the flow rate through a pipe where the pressure is provided by an axial flow impeller, but restricted by an orifice plate. I have (or can get hold of) all the physical...

Thanks! That's given me something to do a little research into. I'd initially discounted it as the speed is onlyl about 50% of critical speed. I'll look into it further. Thanks again.

Does this phenonema occur below the natural frequency? This shaft is rotating well below its natural frequency. From what I've read so far this seems to be the same as resonance at critical speed.

The shaft could well have been slightly bent (and probably was at some stage). The run out would have been less than 1mm over the 3m length. I was just using a straight example to try to grasp the concept. I initially figured if it was bent I could simply sub in (an approximation of) the...