Recent content by Ken Fabian

I think @Lnewqban has it right; the water at the base gets replaced rapidly and mixed with adjacent cooler water whilst the warmer water that rises tends to accumulate at the top, especially if the heating is slow rather than fast enough to cause vigorous overturning and mixing through the whole...

@Baluncore - If I am wrong in this it is wrong with conviction. I don't think I am wrong in this. There is a rebound of water hammer hitting a compressible body of air, be it air in the air chamber in the time before the delivery valve shuts or bubbles before a stuck delivery valve - which...

Diagram, with terminology - which other diagrams may name differently. @Baluncore - I disagree - the amount may be small but there will be some backflow, a physical volume of water returning to the drive pipe before the delivery valve closes. Water compression delivers no additional physical...

It is interesting thinking it through - not so much reading of references in this case; it is good for my brain, whilst noting that what I think sometimes leads to what is correct but sometimes not. In this case it is turning out more complex than my initial thinking, or even my first few...

Nothing like being wrong with confidence.

Okay, I stand corrected. Had been thinking about it and realised that, yes, there needs to be a moment of negative pressure for the waste valve to re-open. The extent to which that is rebound from water compression rather than a product of the pipe expanding and recoiling I am still thinking...

@Baluncore - My experience was with a variant type, so details vary. My non-return valve had a spring and had other differences but principles are the same. Why a straight pipe appears to deliver a better pressure pulse seems a different question to how the 'waste valve' re-opens. On mine the...

That is what the main 'slam valve' does (Not sure of correct terminology). At the start of each cycle water flows down the main water feed pipe and spills out freely, back to the river - effectively a pipe open at both ends - until it is flowing fast enough to slam the valve closed. Most of the...

Whilst every material outside of a black hole is compressible I do think very low compressibility of water is a crucial factor for ram pumps to work. Loose terminology to say 'lack' of compressibility rather than 'very low' perhaps. I think a compression wave passing up to the reservoir is NOT...

Fusion still appears to need an abundance of reaction mass - that might colloquially get called 'fuel' . The fusion engines part seems likely to have a lot of fixed mass, which will require more reaction mass, undercutting some of the gains from high exhaust velocity. There are trade-offs. If...

I built and used one for a time - a variant that included a pressure vessel packed with closed cell rubber rather than just an air chamber - without that there was too much backflow from the non-return valve. It was a design intended for low water 'head' (or drop) and it did work but my site had...

Average prices don't tell the whole story. Given time of use 'free market' pricing the presence of cheap solar for part of each day means a commercial nuclear plant has to sell at under cost during those periods and make up the difference outside those times to remain profitable. It won't be in...

Imaginary technology is one thing - internal consistency about it matters more to me than actual 'scientific' believability. But getting known physics or astronomy etc wrong makes suspending disbelief much harder. The popular ducking and weaving through an asteroid belt is one example. Another...

Where I live in Australia prevalence of tick bites decreases with Winter. With warmer Winter conditions the 'active' time window appears to have widened. Whether numbers have changed (or range - it seems likely) is harder to assess but being active more of the year does increase overall...

I'd be interested to learn how productive the sheep grazing is under that Minnesota solar far compared to without the solar. One of the common complaints about solar and wind is land use and claims of agricultural land being under threat of being overwhelmed. That seemed unlikely to me so I...