34 votes
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What is the purpose of these diversions in a natural gas line?

The loops are known as expansion loops. They need to be placed in pipelines to enable the pipelines to contend with thermal expansion and contraction and other forces that can affect the pipeline. ...
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  • 9,447
15 votes
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What is the most efficient means of warming a building with a high ceiling?

Your question sort of has two parts: How to supply heat, and how to keep it in. Large open rooms with a high ceilings are most efficiently warmed with radiant ceiling heat. Warm air rises, which ...
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  • 1,785
12 votes
Accepted

What's the purpose of these small closet-like-rooms-without-a-door?

I do not know, I've never been there and I have no other information other than what is in your question. However, ... I'd say that best guess, until somebody who knows more presents, is your ...
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8 votes

What is the most efficient means of warming a building with a high ceiling?

Another option to the radiant solution above would be under floor air distribution systems (UFAD) using displacement ventilation. These systems require a raised floor plenum which works well in ...
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  • 377
8 votes
Accepted

Cooling tower for nuclear power plants

The hyperbolic shape of cooling tower is preferred as this shape is stronger against wind pressure. Consequently, the concrete wall thickness can be reduced and optimised. from 1.5m at the base of the ...
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  • 96
5 votes

Tower crane with a cabin on ground level

The crane operator at the top of the tower doesn't just have a view of the load being lifted. He/she can see the entire surrounding area and take account of any potential hazardous situations that ...
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  • 12.5k
5 votes

Is making a toilet flush backwards problematic?

Per the ever informative Snopes The hemisphere doesn't affect the spin of the water. This means that the water spin down the drain is controlled by the design of the drain. This shouldn't be hard to ...
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  • 10.6k
4 votes
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Where to insulate Underfloor air distribution system in a temperate climate

It depends — can you run air through the plenum without simultaneously running the active heating/cooling system? If not, you'll never get the benefit of its thermal storage capacity. For ...
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  • 6,749
4 votes

What is the most efficient means of warming a building with a high ceiling?

Here are some ways to keep the warm air from escaping: Revolving doors prevent a constant stream of air exchange between the inside and outside. Air lock areas - a double-set of sliding doors can ...
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  • 5,930
4 votes
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Is making a toilet flush backwards problematic?

Per the Wikipedia article on the Coriolis effect: Contrary to popular misconception, water rotation in home bathrooms under normal circumstances is not related to the Coriolis effect or to the ...
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4 votes

Recoil of hydraulic lift/elevator

When an elevator stops it will set a brake to immobilize the elevator cabin. This way a sudden leak doesn't drop the cabin while the door is open. When the controller prepares to move the elevator ...
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4 votes

Why don't we make bricks out of coffee grounds?

Bricks are primarily made of sand and clay. The sand acts as a filler, and clay is a substance that has some rather remarkable qualities. Coffee grounds do not exhibit the qualities of sand or clay. ...
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4 votes

What does this equation mean?

The $\propto$ symbol represents proportionality. So, whatever is on the left hand side is directly proportional to cross-sectional area and inversely proportional to volume. Now, as to the actual ...
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  • 13k
4 votes

How would you move a sail boat with no wind or paddles

The answer, despite what several responders think, is unequivocally YES . However, you will get more efficient propulsion just by blowing directly backwards. All a sail does is deflect wind, thus ...
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4 votes

Is a single large impact better than several small impacts for breaking ice

Multiple smaller, light impacts are better. The heavy concentrated impact can damage and crack the already fragile pavement which has likely lost most of its resilience due to the freezing ...
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  • 21k
4 votes

can ceramic be used as a building material?

structural ceramic does have some applications in things like engine parts, but its cost and manufacturing difficulty makes it a less ideal choice for something as large as a building foundation The ...
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4 votes

can ceramic be used as a building material?

One of the foundational principles of structural engineering is obviously safety. And one of the foundational aspects of safety is the ability to show warning signs prior to any accidents. In the case ...
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  • 13k
3 votes

Controlled demolition of a sky scraper?

It is certainly possible, although far from easy and requires very specialist knowledge. First the building will be surveyed in great detail to determine how the loads are carried throughout the ...
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3 votes

What is the most efficient way to ionize air?

It will depend on the degree of ionization you require, as well as the pressure of the air passing through the ionization region. Your gas will not likely be at STP if the air is moving through a ...
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3 votes

Tower crane with a cabin on ground level

It is not trivial to replace human vision with a camera in this sort of situation. it is difficult to reproduce good depth perception with cameras the human eye can change focus quickly and ...
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3 votes

Can a neutrally bouyant helium balloon be suspended in air using magnet entrapment?

Could the top floating peace be place inside a helium balloon buoyantly neutral and stay entrapped in the magnetic field without having to spin? No. The system relies on the gyroscopic stabilization ...
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3 votes

Ventilation setup high sleeper night cooling

I would recommend a modification Phil's answer: airflow is almost always better when the fan is exhausting to the outside - fans don't "like" back pressure and work most efficiently when dumping to an ...
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3 votes

What are the limits on building very high buildings using certain materials and architectural style?

The tallest masonry building erected is the Philadelphia City Hall . It is 548 feet high. The issue with building masonry structures is the walls have to support the weight of the building and the ...
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  • 9,447
3 votes

Cooling tower for nuclear power plants

The shape is to take advantage of the Bernoulli law. The narrower throat of the tower creates reduced pressure encouraging faster convection discharge of warm, moist vapors. Hot water from the ...
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  • 21k
3 votes
Accepted

Can a horizontal foundation safeguard against earthquakes?

Things topple when their center of mass moves past their supports. Think of a square box: if you push it over slightly and let go, it'll fall back onto its original position. But if you push it past ...
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  • 13k
3 votes
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Is it just surface area alone that causes bridges to freeze?

Heat is the transfer of energy from a hotter region to a cooler region. The surface in contact with the earth enjoys the benefit of conductive heating. Being cooler, the energy of the warmer earth ...
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  • 6,192
3 votes

Why did they move ancient Egyptian temples to prevent them from water damage instead of encircling them with a dam?

Shielding them by a dam would have been more costly. And being hidden under a 65 meters deep wall into the water of the Aswan dam would make them visually disappear, and lose their glory. As it is now ...
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  • 21k
3 votes
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Would a larger building more safely or smoothly ride the seismic waves of an earthquake?

Earthquake waves are very long. For example in California, the frequency of the 1996 Northridge earthquake was 0.5Hertz. This shock could cross the diameter of the earth in half an hour (Not correct! ...
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  • 21k
2 votes
Accepted

Recreating Focaults Pendulum

There are two simple options for the bearing The first is to suspend the bob from a flexible cord passing through a fairly tight grommet so it will maintain a constant point of contact in all ...
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2 votes

Tower crane with a cabin on ground level

From 1924 to 1932 Sydney Harbour Bridge was constructed. It used two creeper cranes on both sides of the arch during construction to hoist people & materials. The crane operators couldn't see ...
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