Beam engines

The Stretham steam pumping engine (Fig. 16.8) was built in 1831 as part of an extensive project to drain the Fens for agricultural use. In its day it was one of the largest beam engines in the Fens, having a maximum power of 105 horsepower at 15 rpm (it could... 

The original steam condensers were barometric condensers, which were used to increase the efficiency of the steam-driven reciprocating beam engines by a factor of 10. The barometric condenser was invented by James Watt (the steam engine was invented by Thomas Newcomen). Exhaust steam is mixed directly with cold water. As this creates a vacuum, the barometric condenser must be elevated about 30 ft above grade. The mixed condensate and cooling water drains through a pipe called a barometric leg—hence the name barometric condenser. 

The central idea of our industrialized society is to have machines do the work formerly done by humans or animals. The technical problem that kicked off the industrial revolution was flooding in the tin mines of Cornwall, a region in southern Britain. To work the mines and extract the valuable tin ore, steam-driven reciprocating pumps had been constructed. These plunger-type pumps were moved up and down by the famous beam engines, and these reciprocating engines were powered by steam, thanks to the efforts of Thomas Newcomen, in 1712. 

There was a big problem with the initial beam engine design. When the cold water was admitted into the steam cylinder, the water not only absorbed the latent heat of the condensing steam but also cooled the iron walls of the steam cylinder. Then, when the next charge of steam was admitted to the cylinder from the boiler, a lot of the steam s heat was wasted in reheating the iron walls of the cylinder. Then, again, an awful lot of cold water was wasted in cooling the steam cylinder each time the motive steam had to be condensed. 

The lower the pressure in the steam cylinder, the more forcefully the piston was drawn down. And the more forcefully the piston was sucked down, the more work the beam engine could do with the same amount of coal consumed. 

Yang S.T., Hu X Z, Wu Z.M. 2011 Influence of local fracture energy distribution on maximum fracture load of three-point-bending notched concrete beams. Engineering Fracture Mechanics, (78) 3289-3299. 

Zhang Y.F., Zhao J.H., Cai C.S. 2012. Seismic behavior of ring beamjoints between concrete-filled twin steel tubes columns and reinforced concrete beams. Engineering Structures 39(6) 1-10. 

Stewart, M.G. Suo, Q. (2009) Extent of spatially variable corrosion damage as an indicator of strength and time-dependent reliability of RC beams. Engineering Structures, 31, 198-207. 

There was a big problem with the initial beam engine design. When the cold water was admitted into the steam cylinder, the water not only absorbed the latent heat of the condensing steam but also cooled the iron walls of the steam cylinder. Then when the next... 

Beam Engineering for Advanced Measurements Cranpany, Winter Park, EL 32789, USA e-mail luciano beamco.com luciano.desio fis.nnical.it... 

X. Dai, U. Hrozhyk, S. Serak, N. Tabiryan, Beam Engineering for Advanced Measurements Corporation... 

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