The Ark - materials, construction and seaworthness

No need to affect it at all (over an above the general seaworthiness issues) Consider the pockets to be an internal add-ons onto the existing plain box structure. It depends on how much sludge we are required to pump. That is unknown. We might suppose that the overall ark dimension with all necessary systems is big enough for the task at hand. We have a number of options:Vent out the topVent out the side above the waterlineVent inside (this could - assuming other details take this into account) be used to vent the ark - it is likely to be quite smelly in there) I'll bear it in mind. This is a bespoke item and is not designed around pumps because there were no other pumps around to base the design on. There have been many, many copies of the principles used however. You know those oil well pumps you see out in Texas (at least I think it was there - I saw them on Dallas years ago). They are quite similar although power source rocking the beam is different. Edited by iano, : No reason given.

The housing to contain the disc/float wouldn't be much wider than the float itself. If these were 2 metres in diameter then the housings would nestle nicely in between crossbeams. Besides, the crossbeams could mount against the housing itself and 'transmit' support to the hull via the housing. Thats the chappie. We have our power source sorted (our pump will be sized to suit), connecting rod (via eyes) to the beam, the pivoting beam nodding like a donkey. All we need now it to connect the beam to our submersible pump. Unless there are other considerations (like adapting the housing to to provide ventilation for the arks interior as secondary function)Edited by iano, : No reason given.

I was filling you in on what our contraption looked like in order for you to picture the principle involved in operating the pump. If you are happy with the power generation and transmission we can progress to the submersible pump side of things as required of this application.

I don't need to look at what boreholes and submersible pumps to to be honest. There are a number of pump types that could be considered. What occurs at the end of a nodding donkey may be suitable for our application or it may not. No matter. The pump I have in mind needs to be simple, made out of wood and other reasonably supposed materials and take account of the lay of the land in the application intended. It also needs to be able to pump poo. They are the general considerations that Noah faces. And so do we.As to toilet roll guns. A decent scale model will easily tell whether any of the componants are unfit for use. Every compoonant can be pared down until it begins to struggle so as end up with a reliable, tough full sized version. All the materials necessary in order to determine sizing of the various componants are available: water/wood/poo.People made things with enormous success long before the word engineer was ever thought of. The proofs in the pudding - we're all here aren't we

We're not talking ark design Ramoss we talking poo-removal. We must pre-suppose poo generation in order to suppose a poo-ump I haven't thought the detail out much, but a concept might be sufficient to offset some of your doubt (a list of objections would mean you have considered it - which means your doubts have been offset - until such times as your objections are deemed valid)A box the size of the ark is some structure alright. No doubt about it. Not at all an impossible structure by any stretch of this engineers imagination however. Approach it the way I would approach it. Work it backwards.In your minds eye: begin with a solid lump of wood the size of the ark. The wood is half the density of water in this example (pretty average in fact). Place it on the water and it will float, half under water half over water. But there is no room for animals or anything else. So start hollowing it out. Begin in the very centre of the block. An amazing amount of material can be removed with affecting the strength of the block. Wood is immensely strong in bulk form.As you hollow, buoyancy dictates that the block will float higher in the water - but to compensate you start adding that, which is approx. the same density as water to the void your creating - animals for instance, or a drink water containing storage vessel. Being twice the density they take up only half the volume you have excavated. Keep on hollowing out.As you hollow out, the side walls get (relatively) thinner and the bulk strength of wood reduces in terms of advantage. A point will be reached where the sheer bulk is unable to withstand loads (mainly external pushing inwards) and they will start to bulge in. Start adding bracing at this point. Brace one bulging in wall against the opposite bulging in wall. The bulges cancel each other out. Thin out more and refine your bracing so that it itself doesn't buckle. One might take note from nature and see that triangulation is the best way to brace using relatively slender membersPerhaps add a second function to the cross bracing by adding flooring on top of it. The ark had a base floor, a deck top and 3 floors in between. Over a height of 45 ft it had 5 cross bracing layers. That is 9 ft high walls between layers . Your talking strong. (Of course you could leave out areas of decking for animals taller than 9 ft. A giraffe for instance)Perhaps you observe your washing on the clothe line and decide that you don't want all that wind load and inherant instability which comes from floating half in/out of the water. Simple add more high density material such as more animalsLook at a high tension electricity pylon next time you pass one. All space and little material. See the triangulation. Next time you come across a dead bird take a longtitudinal section of its wing - see the structure Noah saw - little by way of material but lots of triangulation.Noah has wood and glue and any number of joint designs at his disposal. That and his own multi-century smarts.(we are not in a position to comment on that advantage) Add a bit of lamination to the proceedings and you begin to enter the realm of immensely strong structures - the same as if you excavated from a solid block (stronger in fact - a solid block of wood has a grain along which you can get splits and cracks propagating. Not so with laminates)An ark of size stated is not an engineering impossiblity by any means. It is in fact relatively simple. It just requires a lot of what is simple: time (or labour), materials and some basic, commoner garden engineering applicationChocks away!

Ahh. Sorry. Was under the impression I was talking to an engineering mind in this case, not a debater. I withdraw all design outlines presentedEdited by iano, : No reason given.

Its not at all complex razd.Ships roll from side to side.They roll around a longtitudanal axis. Because they do, any point on its hulls side will move closer to/further away from the surface of the water as it rolls from side to sideLower a liftboat, detach from the ship and observe. The ship rolls over. And the lifeboat rises relative to an observer standing on the deck of the ship.Attach a rigid arm between the ship and lifeboat. Roll the ship and watch the lifeboat go under the water - its buoyancy cannot 'resist' the roll of the shipJoin the lifeboat via a non-rigid arm (ie: a crank) and watch the shit hit the (ventilation) fanEdited by iano, : No reason given.

See message 69 for visualisation of a way of harnessing the energy of the sea acting on the ark. You are correct in what you say but that is not what is being proposed.Consider: if a 'lifeboat' float had sufficient buoyancy to carry 40 people without being submerged and that resistance to submersion was instead directed into a pump by the rolling action of the ark then poo you would most certainly pump. Neglecting losses for a moment (the see-saw and connecting arms to float and pump can be neutrally balanced. Well designed and lubricated plain bearings absorb little power) then a column of poo the equivilent weight of 40 people can be supported by the float. All one has to do then is size the waste pipe from pump to above waterline so as to ensure the column of poo in the pipe weighs less than 40 people. Visualise a column of 40 people standing on each others head: say 220 feet. The poo column only has to reach the deck at most: 45 feet from the bottom of the ark.Thereafter, the mechanism is relatively simple - no less complex that an animal driven device. The advantage of this pump over one involving animals is that the energy is 'free' - you don't have to stock food to drive it nor do you have the labour involved in changing the animal teams.The pump system can also have the secondary function of venting the ark. I'm sure I cold think of something else too

An animal operated screw auger would be an easier way of shifting the poo but practically speaking, one of the major constraints on board is manpower. Anything we can do to reduce manpower input on board should be considered before embarking. The complication is increased (a bit - a horse drawn pump is a mechanism too)We might expect the float to leak just like a rowing boat would. Occasional draining would be required. This is relatively easy to achieve. Lock the pump mechanism when rolling has it in a high position and activate a drain or bail it out. Barring catastrophic failure, once a week or so should be enough. Far less labour than chenging teams of animals would entail.You would of course have a number of pumps on board to handle irreparable failure. Its common practice to have backup sytems for such an essential mission. Its not hard to built a reliable, fairly watertight float in any case. The loads are virtually all vertical: tensile and compressive. An earlier post dealt which placing the float and connecting arm in a shaft (like a liftshaft) located against the inside wall of the ark whose bottom is open to the sea. This eliminates drag and wind loading. The water in the shaft moves with the ark and can only rise and fall with rolling - which does not apply side loads We haven't got the manpower available to bail out. And maintaining animals so as they can bail out is too labour intensive. Needs must. Don't get you here

Not really DJ. In discussing this I am presupposing an ark to fit it into in the first place. In using materials for the pump I suppose them to be suitable for general ark building. Which makes them adequate for the purposes proposed.if we can suppose nothing at all then no discussion is possible. So I won't be able to discuss it with you. Your question led to that conclusion for it allowed no assumption

You mean ships only roll when it rains? Gee!

Floats, levers, pivots = back to the future? Simple materials + intelligence. Nothing more is required. And if nothing more is required than that then it is possible. Very possibleYour objections are based on your own presumptions. Fine. But lets not fool ourselves that your presumptions circumvent what is easily possible Edited by iano, : No reason given.

Some mech eng terms you apply:statically deterinate, thermal analysis, tolerances, calculus, stastistics, thermodynamics etc, etcIf you were cast on a desert island with some basic tools and could not manufacture a pump based on a reciprocating float then a mechanical engineer you are not.Edited by iano, : No reason given.

To be honest, I'm slightly bemused by the cries of 'evidence'. I'm not saying that Noah has this pump, that pump, or any pump.A person who decides to build an ark 4000 or whatever years ago can so decide. There is nothing at all to stop them so deciding. Immediately they are faced with problems, in this case: "how do I deal with the issue of poo removal (if they decided that that was as issue)?" And if they decided it is a problem then they can begin to figure out ways around it. And if the solutions do not require anything other than intelligence and simple materials then such solutions are eminantly possible."Man hadn't progressed this far" is a red-herring. It seeks to sidestep the fact that there is nothing at all stopping Noah by introducing general argument against the Ark (ie: the standard evo timeline for mans development)The most amusing objection along these lines was the one which demanded that Noah first be in possession of concepts such as "statically determinate", "thermal analysis", "tolerances", "calculus", "ststistics", "thermodynamics etc"...before he could even begin to startAs if man achieved this before he started making machines..

I agree that some assumptions need to be made but I am far from invoking semi-conductor technology in Noahs day on the basis that "there was nothing stopping him." There is nothing in the design that could not be extracted from plain observation of simple mechanical concepts such as buoyancy, levers , pivots etc.We had Paisano earlier enquiring into thermal analysis and bursting pressures as if such a pump even approached a complexity level requiring such notions.If we take the ark as being 45 foot tall and assume half that under water then the pressure on the pump (and anything involved in driving it) is a mere 0.66 Bar (not incl losses). Thats 9.3 lbs/sq inch. (nearly the pressure I place on the floor if I stand on one foot) This is not pressure - this is a pittance. The very weakest of woods are around this strong. The very strongest woods, 150 times this strong. Sure we do not know the wood type. But is it not reasonable to assume the availability of trees and assume a wood strength somewhere in the middle?And why one would invoke 'thermal analysis' for a slow moving (the ark was not a cork - its period of rolling would have been longish) low pressure pump which is immersed in cooling fluid is beyond me.This is not "I don't think it can be done" this is "I know it could be done but I will put in any obstacle I can - no matter how silly"