Mechanical Power Production Research Articles

Cogeneration with wood fuels: A review

Cogeneration is the sequential production of electricity or mechanical shaft power and useful heat at the same facility. While all fuels can be used in this mode of power generation, wood is a prime candidate for use in such systems. Four basic cogeneration cycles exist: the steam turbine topping cycle, the gas turbine topping cycle, the diesel topping cycle, and the bottoming cycle. Of these, the steam turbine topping cycle is most appropriate for wood. In this cycle high pressure steam is expanded through a turbine and exhausted at industrial process conditions. The size and continuity of operation of the industrial facility normally determines whether cogeneration is appropriate and economic. The process requirements dictate exhaust steam conditions. Cogeneration systems are more efficient than condensing power systems. Typical heat rates are 4500–6500 Btu/kWh depending upon the design and operation of the boiler and associated turbine-generator. Benefits exist because of these favorable heat rates in the areas of capital cost, thermal efficiency, choice of fuel, and airborne emissions.

The mechanochemical turbine: a new source of power

The basic thermodynamic cycle for the production of mechanical power from materials that may be made to contract forcibly and reversibly is described. The cycle differs from existing mechanical power cycles, which generally employ expanding fluid as working substances. A ‘contraction turbine’ operating on this cycle has been devised, which has collagen fibre as its working substance and salt solution as fuel and produces mechanical -work directly from chemical free energy. Direct conversion of chemical to mechanical energy is routinely effected in muscle, but not in usual man-made engines.

Mechanochemical turbine: a new power cycle.

A basic thermodynamic cycle for the production of mechanical power from materials that may be made to contract forcibly and reversibly is described. The cycle differs from existing mechanical power cycles which generally employ expanding fluid as working substances. A "contraction turbine" operating on this cycle has been devised, which has collagen fiber as its working substance and salt solution as fuel and produces mechanical work directly from chemical free energy. Direct conversion of chemical to mechanical energy is routinely effected in muscle but not in usual man-made engines.

Use of solar energy for mechanical power and electricity production by means of piston engines and turbines

Use of solar energy for mechanical power and electricity production by means of piston engines and turbines

Use of solar energy for production of mechanical power and electricity by means of piston engines and turbines

Use of solar energy for production of mechanical power and electricity by means of piston engines and turbines

The Development of Mechanical Power in the Last Decade

E VEN as we are accustomed to think of history as divided into epochs, having more or less well-defined limits, so the future historian will undoubtedly define the present era probably as the age of the industrial revolution. One of the chief agencies, probably the principal agency, in this revolution is the production of mechanical power. Few realize, as they go about their daily affairs, how indispensable is this commonplace thing to modern life. Subtract all of its results and see what we have left: rapid transit by stage coach, every convenience depending upon the application of electricity eliminated; home-spun clothes, little variety of food, little or no ice; little communication between distant individuals, few books and no newspapers. In short, subtract everything that is wholly or in part dependent upon power, and how much of the progress of the last thousand years would be apparent? While we have gone far and fast in the production of power to meet the continually increasing demands of an industrial age, when we consider the lavish supply of materials for its production with which the earth is stored, and the fact that most of it is wasted through ignorance and inefficient methods, we must humbly admit that the art of producing mechanical power is still in its infancy. In the most successful attempt that man has made to utilize the forces of nature for this purpose, the development of the water fall, he is able to realize only about 33 per cent of the actual power of the water in useful work performed. In plants which derive their power from stored heat energy the showing is much less favorable, the work of the street car in ton miles or the candlepower of the electric lamp being commonly less than two per cent of the equivalent heat energy stored in the coal. Percentages make little impression on the mind unaccustomed to dealing with these matters. Let us put the statement in a little more startling way. In 1908, an average year,