Recent content by bigaggie

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    Whether A Pump with Gear Box (to increase pump speed) is Feasible?

    If the curve is relatively flat, then yeah you really shouldn't have recirculation running back a little bit (though I've seen it before). Most manufacturers allow for you to run about 70-110% of BEP. But he's talking all the way back to 50% (assuming he's at 100% now). Even on a flat curve...
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    Whether A Pump with Gear Box (to increase pump speed) is Feasible?

    I cannot begin to tell you how bad of an idea this is. Really. Very. Bad. If you run a pump like this back on the curve that far, you will almost certainly experience higher vibrations, most likely due to discharge recirculation, and that could have a significant impact on pump...
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    Whether A Pump with Gear Box (to increase pump speed) is Feasible?

    Are you sure on that flowrate? There's only a handful of pumps in the world that can push that amount, and last I checked none of them ran at 3000 rpm. In my experience, you have 3 options. 1) Gearbox. Yes, it is done, but normally not for something like this. I usually see it in instances...
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    Does anyone in the US use A4-sized notebooks?

    Moleskine makes an A4 sized notebook in both ruled and squared formats. I use the ruled one at work to log all of my calculations/project notes in.
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    Engineering Do all engineers have to do hands-on work except PhDs?

    I'm a little confused as to your major. Are you EE or MechE? I have my Bachelor's in MechE, and have worked for my current employer for almost 4.5 years now. My first 3 I spent in a repair facility as a shop engineer, which was a fancy term for 'walking Swiss Army knife', but I spent many hours...
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    Selection of Pump for Parts Cleaning Machines

    I agree with everything you said but this. I'm not sure about positive displacement pumps (gear pumps, piston/plunger pumps, etc.), but for centrifugal pumps it's actually the opposite due to the design of the impeller inlet. Damage is usually more severe when you're beyond BEP by 10%, normally...
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    Language for Bearing Program

    Thanks for the help guys. Looks like we'll have to find a co-op or something (we're a bunch of mech engineers).
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    Language for Bearing Program

    So, my company has quite a few old programs for calculating solutions to bearings, annular seals, etc. The calculations are iterative in nature, and none of these old programs are really integrated together, which is problematic. Plus they're in Fortran (or something else), and don't run on our...
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    Head for a Pump

    It can be done, but it's not very straightforward. There are several "modeling" equations that can be used to predict performance based on the geometry of the impeller (or plungers if a piston pump), but you are correct, the only real way to know how a pump will perform is to test it. That...
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    Send radioactive waste to bottom of the ocean?

    Totally unrelated, and I agree with your point, but if I remember Ballard's assessment correctly, the biggest issue causing the Titanic's corrosion is that the water it sits in is very stagnant. If it were in an area with a current, chances are the microorganisms wouldn't have attacked quite as...
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    Programming Languages used in High School Robotics

    Yeah, Python's probably the easiest to learn and apply to robotics, as jedi pointed out. However, if you find yourself wanting to get really hardcore and want a more difficult challenge, C++ would probably be my second choice.
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    Igntion system suggestions/considerations

    I suppose you would need a lot of other parts if you really want this to look nice, but if you're just concerned with lighting it up, you can probably take the coil from an automotive ignition system and rig a switch and a wire to it. Just run to the local automotive junkyard and rob the...
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    Shaft Critical Speed Considerations

    There's a lot of stuff to deal with here... Let me define what I mean by "dynamic." What I mean to say is that it is a force that only occurs when the system is in operation, not static or motionless. Let's think on this force some more (by the way, I got confused in my last post, I was...
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    Shaft Critical Speed Considerations

    I'll take a stab at this, though I'm still pretty early on in my rotordynamics analysis career, so I wouldn't call anything I say gospel without fact-checking. I think you're getting some stuff mixed up. The natural frequency of the rotor is a property inherent to the design of that rotor...
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    Challenges in creating a 3D printer

    I would think you have three major challenges 1)Temperature- you have to literally melt whatever metal you're trying to work with to the other particles of metal...without sticking to your baseboard, and without melting everything else around it. Could be difficult. 2) Cost- sounds like you're...