Heat engine gas turbines

E.. Schmidt. M.A., Shirley, G., Spearing, S.M..Tan. C.S.,Tzeng, Y.S.and Waitz, LA. (1997) Micro-heat engines, gas turbines and rocket engines - The MIT Microengine Project, paper 97-1773, 28th AlAA Fluid Dynamics Conference. 

Karim AM, Federici JA, Vlachos DG (2008) Portable power production from methanol in an integrated thermoelectric/microreactor system. J Power Sources 179 113-120 Epstein AH, Senturia SD et al (1997) Micro-heat engines, gas turbines and rocket engines—the MIT microengine project. Paper 97-1773, Twenty-eighth AIAA fluid dynamics conference... 

Spray Combustion - Diesel Engines - Spark Ignition Engines - Gas Turbines - Rocket Engines - Industrial Furnaces - Domestic Heating Boiler... 

The central problem in efficiently using wood for the decentralised production of heat and power has been the gas clean-up process. Tars and particles need to be removed efficiently to prevent depositions or excessive wear in the power conversion devices (gas engines, gas turbines).The problems and costs associated with efficient gas cleanup, especially for the conversion or removal of tars, have not been solved so far in a satisfactory way and have hindered the wide-spread introduction of gasificahon as a means of utilising fuel wood with high exergy efficiency. 

Cobalt is a component of the so-called superalloys used to make critical parts of jet engines, gas-turbines, and of other machines operating under stress at high temperatures. It is also a component of the so-called stellites. These alloys are composed of 50-60% cobalt, 30-40% chromium and 8-20% tungsten, and are valued for their extreme hardness, strength, and heat resistance. In addition, cobalt is a component of magnetic steels and aluminum alloys with superior ferromagnetic properties. In 1975,... 

Nickel is a constituent of many metal alloys (e.g., Ni-Cr-Fe alloys for cooking utensils and corrosion-resistant equipment Ni-Cu alloys for food processing, chemical, and petroleum equipment, and for coinage Ni-Al alloys for magnets and aircraft parts Ni-Cr alloys for heating elements, gas-turbines, and jet-engines). Alloys of nickel with zinc, manganese, cobalt, titanium, and molybdenum are used for special industrial purposes, and alloys of nickel with precious metals are used for jewelry. 

A more complex utility is combined heat and power (or cogeneration). Here, the heat rejected hy a heat engine such as a steam turbine, gas turbine, or diesel engine is used as the hot utility. 

Now let us take a closer look at the two most commonly used heat engines (steam and gas turbines) to see whether they achieve this efficiency in practice. To make a quantitative assessment of any combined heat and power scheme, the grand composite curve should be used and the heat engine exhaust treated like any other utility. 

Appllca.tlons. The principal appHcations of nickel-base superalloys are in gas turbines, where they are utilized as blades, disks, and sheet metal parts. Abcraft gas turbines utilized in both commercial and military service depend upon superalloys for parts exposed to peak metal temperatures in excess of 1000°C. Typical gas turbine engines produced in the United States in 1990 utilized nickel and cobalt-base superalloys for 46% of total engine weight (41). However, programs for future aerospace propulsion systems emphasize the need for lightweight materials having greater heat resistance. For such apphcations, intermetallics matrix composites and ceramic composites are expected to be needed. 

High Temperature. The low coefficient of thermal expansion and high thermal conductivity of sihcon carbide bestow it with excellent thermal shock resistance. Combined with its outstanding corrosion resistance, it is used in heat-transfer components such as recuperator tubes, and furnace components such as thermocouple protection tubes, cmcibles, and burner components. Sihcon carbide is being used for prototype automotive gas turbine engine components such as transition ducts, combustor baffles, and pilot combustor support (145). It is also being used in the fabrication of rotors, vanes, vortex, and combustor. 

ASME, Performance Test Code on Gas Turbine Heat Recovery Steam Generators, ASME PTC 4.4 1981, American Society of Mechanical Engineers Reaffirmed 1992. 

One of the major funetions of the eombined eontrol-proteetion system is to perform the startup sequenee. This sequenee ensures that all subsystems of the gas turbine perform satisfaetorily, and the turbine does not heat too rapidly or overheat during startup. The exaet sequenee will vary for eaeh manufaeturer s engine, and the owner s and operator s manual should be eonsulted for details. 

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