Turbine system

Has enough flexibiUty been built into the overall condensing turbine system (The balance changes over the history of a unit as a process evolves, generally in the direction of less condensing demand.)... 

Validation and Application. VaUdated CFD examples are emerging (30) as are examples of limitations and misappHcations (31). ReaUsm depends on the adequacy of the physical and chemical representations, the scale of resolution for the appHcation, numerical accuracy of the solution algorithms, and skills appHed in execution. Data are available on performance characteristics of industrial furnaces and gas turbines systems operating with turbulent diffusion flames have been studied for simple two-dimensional geometries and selected conditions (32). Turbulent diffusion flames are produced when fuel and air are injected separately into the reactor. Second-order and infinitely fast reactions coupled with mixing have been analyzed with the k—Z model to describe the macromixing process. 

Fig. 25. Schematic of large fossil steam turbine system where BFPT = boiler feed pump turbine. To convert MPa to psi, multiply by 145.

Flexibility of service and fuels are criteria, which enhance a turbine system, but they are not necessary for every application. The energy shortage requires turbines to be operated at their maximum efficiency. This flexibility may entail a two-shaft design incorporating a power turbine, which is separate and not connected to the Gasifier unit. Multiple fuel applications are now in greater demand, especially where various fuels may be in shortage at different times of the year. 

Figure 1-16. A oogeneration mioro-turbine system paekage. (Courtesy Ingersoii Rand Corporation.)...

Lane, A.W., and Hoffman, P.A., The U.S. Dept, of Energy Advanced Turbine System Program , ISROMAC-7, Hawaii, 1998. 

Critical speeds of a turbine operating below its first critical should be at least 20% above the operating speed range. The term commonly used for units operating below their first critical is that the unit has a stiff shaft, while units operating above their first critical are said to have a flexible shaft. There are many exciting frequencies that need to be considered in a turbine. Some of the sources that provide excitation in a turbine system are ... 

A Btu meter may be used in the fuel-quality system as an aid in determining turbine system efficiency. A water capacitance probe is used for detection of water in the fuel line. A water-detecting device can be incorporated into the corrosion monitoring system. This monitoring device is based on detection of changes in the dielectric constant of unknown fluid components... 

El-Masri, M.A. (1988), GASCAN—an interactive code for thermal analysis of gas turbine systems. ASME J. Engng Power Gas Turbines 110. 201-209. 

Rabovitser, J.K., Khinkis. M.J., Bannister. R.L. and Miao, F.Q. (1996), Evaluation of thermochemical recuperation and partial oxidation concepts for natural gas-fired advanced turbine systems, ASME paper 96-GT-290. 

Bannister, R. L. Clieruvu, N. S. Little, D. A. and McQuiggan, G. (1995). Development Requirements for an Advanced Gas Turbine System. TnusActions of the ASME, Journal of Engineering for Gas Turbines tuid Power 117 724-733. 

Diakunchak, I. S. Bannister, R. L. Huber, D. J. and Roan, F. (1996). Technology Development Programs for the Advanced Turbine Systems Engine. ASME Paper 96-GT-5. 

Energy recovery turbine systems are available for very high pressure RO (seawater) plants, whereby brine reject water under high pressure can be used to spin an energy recovery turbine, reducing the RW hp requirements (and hence electricity costs) by 30 to 32%. 

Aalto, J.S. Steam Turbine Systems for Power Plant Auxiliary Drives. Journal of the National Association of Power Engineers. NAPE, USA, 1994. 

The problem of alkali deposition in biomass-fueled turbine systems can be a major problem with direct combustion... 

Gas turbine systems operate on the thermodynamic cycle known as the Brayton cycle. In a Brayton cycle, atmospheric... 

Figure 5.10 illustrates the use of this method to extend a Newtonian power curve in the laminar region into a non-Newtonian power curve. The full line is the Newtonian power curve obtained by Rushton, Costich and Everett for a flat blade turbine system. The dashed line is a plot of the data of Metzner and Otto for shear thinning liquids. 

The fuel cell system emits much less carbon into the air than a combustion-based power plant. Less than one percent of the amount is produced from generating the same amount of power. The system is more expensive, costing several times as much per kilowatt-hour (kWh) of electricity produced than energy from a new natural gas fired turbine system. 

Power Generation by Combined Fuel Cell and Gas Turbine Systems... 

The combination of the fuel cell and turbine operates by using the rejected thermal energy and residual fuel from a fuel cell to drive the gas turbine. The fuel cell exhaust gases are mixed and burned, raising the turbine inlet temperature while replacing the conventional combustor of the gas turbine. Use of a recuperator, a metallic gas-to-gas heat exchanger, transfers heat from the gas turbine exhaust to the fuel and air used in the fuel cell. Figure 9-23 illustrates an example of a proposed fuel cell/turbine system. 

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