Gas turbine modeling

In die simulation model, die FCC system was subdivided into discrete elements and suitable subsystems. This model provided all die process parameters such as pressures, flowrates, and temperatures. Figure 6-44 shows die corresponding block diagram. (The model for die expander, piping systems, and vessels is based on a gas turbine model described by GHH Borsig in a paper by W. Blotenberg.)... 

For resistance against fatigue, Nimonic 75 has been used with Nimonic 80 and Nimonic 90. Nimonic 75 is an 80-20 nickel-chromium alloy stiffened with a small amount of titanium carbide. Nimonic 75 has excellent oxidation and corrosion resistance at elevated temperatures, a reasonable creep strength, and good fatigue resistance. In addition, it is easy to press, draw, and mold. As firing temperatures have increased in the newer gas turbine models, HA-188, a Cr, Ni-based alloy, has recently been employed in the latter section of some combustion liners for improved creep rupture strength. 

Meier, W., Duan, X. R., and Weigand, P, Investigations of swirl flames in a gas turbine model combustor—II. Turbulence-chemistry interactions. Combust. Flame, 144, 225, 2006. 

The correlating parameters for variation power and heat rate with ambient temperature are specific to a particular gas turbine model. The parameters in the model can be determined from detailed simulation of the gas turbine or by fitting operating data from existing gas turbines, under different operating conditions. 

Cost of GasificatUm-Tiased Power Systems Comparing power options is complicated by the many different parameters that must be considered in making a cost determination coal cost coal properties, inclnding sulfur and moisture contents ambient temperature degree of process integration gas turbine model and gas cleanup method. These, and many other factors, have a significant impact on cost. 

Ghaffarpour, M., and B. Chehroudi. 1993. Experiments on spray combustion in gas turbine model combustor. Combustion Flame 92 173-200. 

The more common method could best be described as the Equation Oriented Method (EOM). A good example of this method s use is by Schobeiri et al. [6], who applied it to detailed gas turbine modeling. Individual models are divided into two main types of elements, flow elements and pressure elements. 

A thorough introduction to gas turbine theory is provided in (Cohen et al, 1987). There also exists a large literature on the modeling of gas turbines. Model complexity varies according to... 

The concept of the gas turbine control system, which is applied in this chapter, is based on the Speedtronic Mark 4 description as presented in (Rowen, 1988). Some considerations concerning the subject may be also found in (Hannett and Afzal Khan, 1993 Hannett et al, 1995 Jurado et al, 2002). The simplified gas turbine model is divided into two interconnected subsystems. The subsystems are the fuel system (fuel valve with actuator), and the turbine. The fuel flow out from the fuel systems results from the inertia of the fuel system actuator and of the valve positioner. 

Gas turbine model PG5371 (PA) PG6541 (B) PG7111 (EA) PG7221 (F) PGLM2500-PE PGLM5000-PC PGLM6000-PA ... 

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. 

The molybdenum, tungsten and tantalum concentration influence on LCD nickel-ferrous HRS resistance, used for gas turbine installations parts is investigated. The tests were carried out on modeling compositions. Samples were molded on the basis of an alloy of the ZMI-3C. The concentration of tantalum varied from 0 up to 5% with a step of 0,5%. The contents of elements were determined by a spectral method. 

Nickel and its alloys form another important class of non-ferrous metals (Table 1.3). The superb creep resistance of the nickel-based superalloys is a key factor in designing the modern gas-turbine aero-engine. But nickel alloys even appear in a model steam engine. The flat plates in the firebox must be stayed together to resist the internal steam pressure (see Fig. 1.3). Some model-builders make these stays from pieces of monel rod because it is much stronger than copper, takes threads much better and is very corrosion resistant. 

VFO works well in gas turbines. In a nine-month test program, the combustion properties of VFO were studied in a combustion test module. A gas turbine was also operated on VFO. The tests were conducted to study the combustion characteristics of VFO, the erosive and corrosive effects of VFO, and the operation of a gas turbine on VFO. The combustion tests were conducted on a combustion test module built from a GE Frame 5 combustion can and liner. The gas turbine tests were conducted on a Ford model 707 industrial gas turbine. Both the combustion module and gas turbine were used in the erosion and corrosion evaluation. The combustion tests showed the VFO to match natural gas in flame patterns, temperature profile, and flame color. The operation of the gas turbine revealed that the gas turbine not only operated well on VFO, but its performance was improved. The turbine inlet temperature was lower at a given output with VFO than with either natural gas or diesel fuel. This phenomenon is due to the increase in exhaust mass flow provided by the addition of steam in the diesel for the vaporization process. Following the tests, a thorough inspection was made of materials in the combustion module and on the gas turbine, which came into contact with the vaporized fuel or with the combustion gas. The inspection revealed no harmful effects on any of the components due to the use of VFO. 

Aerothermal analysis This pertains to a detailed thermodynamie analysis of the full power plant and individual eomponents. Models are ereated of individual eomponents, ineluding the gas turbine, steam turbine heat exehangers, and distillation towers. Both the algorithmie and statistieal approaehes are used. Data is presented in a variety of performanee maps, bar eharts, summary eharts, and baseline plots. 

El-Ma.sri. M.A. (1986c), On thermodynamics of gas turbine cycles Part II Model for expansion in ctxjled turbines. ASME J. Engng Power Gas Turbines 108. I.S1-1.S9. 

T.C. Lieuwen and V. Yang, eds. Combustion Instabilities in Gas Turbine Engines Operational Experience, Fundamental Mechanisms, and Modeling. Progress in Astronautics and Aeronautics, Vol. 210, AlAA, 2005. 

To model a gas turbine, it is convenient to define the fuel-to-air ratio and steam-to-air ratio ... 

Equation 23.25 has the same basic form as the linear Willans Line Equation used to model steam turbines. The basic assumption behind the use of Equation 23.25 is that the gas turbine would need to have a control system that would maintain a fixed fuel-to-air ratio and steam-to-air ratio at part-load. 

The gas turbine performance at part-load follows the same basic form as that for steam turbines illustrated in Figure 23.10, with the mass flowrate defined in terms of the mass flowrate of fuel. Thus, the part-load gas turbine performance can be modeled as4,9 ... 

Site composite curves can be used to represent the site heating and cooling requirements thermodynamically. This allows the analysis of thermal loads and levels on site. Using the models for steam turbines and gas turbines allows cogeneration targets for the site to be established. Steam levels can be optimized to minimize fuel consumption or maximize cogeneration. A cost trade-off needs to be carried out in order to establish the optimum trade-off between fuel requirements and cogeneration. 

The primary zone of a gas turbine combustor is modeled as a perfectly... 

R. Gemmen, et al, Technical Development Issues and Dynamic Modeling of Gas Turbine... 

Heat engines that use gases as the working fluid in an open system model are treated in this chapter. The modern gas turbine engine operates on the Brayton cycle. The basic Brayton cycle consists of an isentropic compression process, an isobaric combustion process, an isentropic... 

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