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Recent content by ccfowler

  1. ccfowler

    Parallel Pump Operations

    Parallel pump system operations can get very weird very easily. Identical pumps with identical motors connected by functionally identical piping configurations are the non-existent ideal. The messy end of the spectrum involves dissimilar pumps connected at different points within a complex...
  2. ccfowler

    Flow requirements

    EdStainless and Artisi are absolutely correct that over-sizing pumps results in efficiency and maintenance burdens (stars to both!). I fully agree and have made similar statements many times. In my view, the apparently simple 10% margin requirement is not bad on its own because that is a...
  3. ccfowler

    power turbine lubrication system failure during start up

    It wouldn't hurt to verify the actual condition and composition of the lube oil. Contamination, non-conforming make-up additions, etc. may result in property changes just enough to cause or magnify troubles while the oil appears to be in good condition. Valuable advice from a professor many...
  4. ccfowler

    Gas turbines fuel gas valves seals resitant to high temperature

    Seems to me that you are looking to take on lots of needlessly troublesome and costly problems in order to chase a trivial improvement in efficiency. It is not likely to provide a favorable cost vs. benefit situation. The efficiency losses associated with the increased operating problems will...
  5. ccfowler

    Air compressor

    EdStainless's recommendations are assuredly an excellent starting point to sorting out your problem. I've dealt with similar problems, and isolating and testing the true performance of each compressor was the most valuable step. Pay careful attention to every aspect of the problem. You may...
  6. ccfowler

    How does the smart grid play a part or support a wide-scale system for charging electric vehicles?

    davidbeach, you are absolutely correct! What energy goes into a battery is always substantially more than the energy that comes out! Whenever subsidies are required on a continuing basis for something, it inherently cannot be truly viable. Currently, EV's are the beneficiaries of significant...
  7. ccfowler

    How does the smart grid play a part or support a wide-scale system for charging electric vehicles?

    Plug-in electric vehicles introduce very substantial parasitic losses that almost everyone conveniently omits from discussions of their sublime wondrousness. These include step up losses at the power generation site, transmission losses, step down losses, distribution losses, step down losses to...
  8. ccfowler

    Noob Question Re: Woodchipper

    Wood chippers involve relatively significant rotational inertia in addition to shock loads. I would want to include a torque converter at the engine flywheel to temper the effects of acceleration to running speed and instantaneous torque variations from both the engine and the wood chipper...
  9. ccfowler

    Lubrication

    DwaliX, Your question provides little useful information to aid other in providing a more useful answer. If your concern is based on an operating temperature problem, be sure to get very good, well-informed advice. It is not unusual to find that switching to a more viscous oil because of high...
  10. ccfowler

    How can I calculate the volume inside a pump case?

    My view of this question may be somewhat different while sharing much with LittleInch. If this were a very high energy pump, such as a multi-thousand horsepower boiler feed pump, that would suffer from a very rapid and damaging temperature rise during a shut-off condition, nobody in their...
  11. ccfowler

    Venturi flowmeter - without upstream tapping

    Perhaps I should clarify my perspective and concerns. Getting a system working seemingly nicely during startup makes everything nice for the designers and installers, and it may make operations happy for a while. It gets the construction and startup bills paid. Later, there is no small risk that...
  12. ccfowler

    Venturi flowmeter - without upstream tapping

    ATPD, You said the magic words indicating that you have ductwork between the atmospheric air supply and the Venturi flow meter. Thus, you have an unknown restriction between the atmospheric pressure and the true upstream pressure needed for accurate and repeatable meter performance. The inlet...
  13. ccfowler

    Best pump(s) to bring water uphill (700 meters altitude)?

    From what I have read so far, it seems to make the most sense to use multiple small pumps since you need to distribute water along the way from the river to the top. It makes no sense to pump water all the way to the top to simply let most of it flow back down the hill by gravity. Using...
  14. ccfowler

    Hydraulic Power Recovery Turbine (HPRT) Design Questions

    Back in the 1970's, some of the major US pump manufacturers published information on select models of their pumps being applied to just such a duty. I recall reading some of this literature at the time, and all aspects of using these pumps as turbines were addressed very thoroughly. The...
  15. ccfowler

    Installed Cost of a Steam Plant

    Without providing much more definitive information, you cannot expect any meaningful answer. Valuable advice from a professor many years ago: First, design for graceful failure. Everything we build will eventually fail, so we must strive to avoid injuries or secondary damage when that failure...

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