Compound Engines |
Common terms and phrases
50 pounds air-pump area of piston back pressure boiler pressure British Thermal Units cent clearance compound engine condensing apparatus condensing engine cylinder areas divided by number double expansion equal evaporated example exhaust steam Find effective area Find initial press Find mean eff Find mean effective Find mean forward foot-pounds high-pressure cylinder initial pressure injection water jet condenser L. P. Cyl L. P. Cylinder loss low press low pressure cylinder mean back press mean effective pressure mean forward press minus back press multiplied by Hyp multiplied by number non-condensing engine number of ex number of expansions pansions Piston speed 750 pound of water pounds abso pounds absolute pounds gauge product of piston ratio of cylinder revolutions per minute Rule.-Forward press Rule.-Initial press Rule.-Terminal pressure single cylinder engine square inch stroke SURFACE CONDENSERS temperature terminal pressure Total Expansions triple expansion engine vacuum volume of steam
Popular passages
Page 44 - I call the steam vessel, must, during the whole time the engine is at work, be kept as hot as the steam that enters it ; first by enclosing it in a case of wood, or any other materials that transmit heat slowly; secondly, by surrounding it with steam or other heated bodies...
Page 136 - ... degree of moisture or saturation. It is also called the theoretical expansion curve. Expansion Curve. The curve traced upon the diagram by the indicator pencil, showing the actual expansion of the steam in the cylinder. First Law of Thermodynamics. Heat and mechanical energy are mutually convertible. Power. The rate of doing work, or the number of foot-pounds exerted in a given time. Unit of Work. The foot-pound, or the raising of one pound weight one foot high. First Law of Motion. All bodies...
Page 44 - Secondly. In those engines that are to be worked wholly or partially by condensation of steam, the steam is to be condensed in vessels distinct from the cylinders, though occasionally communicating with them. These vessels I call condensers, and whilst the engines are working they ought to be kept as cool as the air in the neighbourhood by the application of water or other cold bodies.
Page 17 - The action of the piston as it nears the end of the stroke, in reducing the volume and raising the pressure of the steam retained in the cylinder ahead of the piston by the closing of the exhaust valve. Boyle's or Mariotte^s Law of Expanding Gases. "The pressure of a gas at a constant temperature varies inversely as the space it occupies.
Page 13 - ... said cylinder, and using the elastic forces, wherewith the said steam expands itself in proceeding to occupy larger spaces, as the acting powers on the piston through the other parts or portions of the length of the stroke of the said piston...
Page 136 - ... raise a pound of water from 39° to 40° Fahrenheit. The range from 39° F. to 40° F. is used because at this temperature water has its maximum density. This unit is called a British Thermal Unit, and is denoted by BTU The heat unit used in Marks and Davis tables is the "mean BTU...
Page 131 - Percentage of builders' rated horsepower developed per cent. ECONOMIC RESULTS. 68. Water apparently evaporated under actual conditions per pound of coal as fired. (Item 57 divided by Item 25) pounds 69.
Page 13 - My improvement in steam engines consists in admitting steam into the cylinder or steam vessels of the engine only during some part or portion of the descent or ascent of the piston of said cylinder, and using the elastic forces. wherewith the said steam expands itself in proceeding to occupy larger spaces as the acting powers on the piston through the other parts or portions of the length of the stroke of said piston.
Page 130 - CURVE. 47. Another point for explanation is that there is a special curve which represents the expansion of a gas when confined in a vessel which possesses the imaginary property of not suffering any heat to pass through its substance, and where the gas is doing external work during its expansion.
Page 43 - Table,page 125, the temperature is seen to be 375 degrees; but by the time the piston has reached the end of the stroke, the pressure...