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Full Version: Concrete tent + Passive solar home + Oil circuit breakers: Types, working & constr...
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Concrete Tent
http://engineering.curiouscatblog.net/20...rete-tent/

EXCERPT: This shows a cool engineering innovation: canvas-like material that when it is saturated with water will set (over 5+ hours) into hard concrete. In this example a “tent” with regular doors is covered with water and inflated. After setting it hard enough to climb on top of....



Structural Engineering Blog: Passive Solar Home
http://www.sturdystructural.com/blog/str...solar-home

EXCERPT: ​There are two main ways modern civil engineering achieves solar energy-based buildings: it builds / retrofits and designs homes using solar heating systems or it builds passive solar gathering homes. In a passive solar building, all elements – walls, roofs, windows and floors – are designed to gather, store and evenly distribute solar energy in the form of heat during the cold months and reject solar heat during the hot season. Everything lies on the shoulders of the design itself and on a few other features we will take a look at next. [...] The passive solar home represents a holistic approach and it is interdependent of the regional climate you live in and the actual site you build on. You can build a passive solar home in an area where the sun doesn’t shine 24/7 all year long, but you should choose the land wisely...



Oil Circuit Breakers - Types, Working and Construction
http://www.studyelectrical.com/2016/06/o...ction.html

EXCERPT: In oil circuit breakers, some insulating oil (e.g., transformer oil) is used as an arc quenching medium. When the contacts of the oil circuit breaker are opened under oil and an arc is struck between them. The heat of the arc evaporates the surrounding oil and dissociates it into a substantial volume of gaseous hydrogen at high pressure. The hydrogen gas occupies a volume about one thousand times that of the oil decomposed. The oil is, therefore, pushed away from the arc and an expanding hydrogen gas bubble surrounds the arc region and adjacent portions of the contacts. The arc extinction is facilitated mainly by two processes.

1. Firstly, the hydrogen gas has high heat conductivity and cools the arc, thus aiding the de-ionisation of the medium between the contacts.

2. Secondly, the gas sets up turbulence in the oil and forces it into the space between contacts, thus eliminating the arcing products from the arc path.

The result is that arc is extinguished and circuit current interrupted. Advantages and Disadvantages of Oil CB...