The Study of the Effects of Gas Turbine Inlet Air Cooling on the Heat Recovery Boiler Performance

Volume 1 ◽  
2004 ◽  
Author(s):  
Mohammad Ameri ◽  
Hamidreza Shahbaziyan ◽  
Hadi Hosseinzadeh
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Flue Gas ◽  
Gas Turbines ◽  
Heat Recovery ◽  
Cooling System ◽  
Combined Cycle ◽  
Heat Recovery Boiler ◽  
Air Cooling

Heat recovery steam generators (HRSG) are widely used in industrial processes and combined cycle power plants. The quantity and the state of the produced steam depend on the flue gas temperature and its mass flow rate. Two key factors, which affect those parameters, are the ambient temperature and the load of the gas turbines. The output power of the gas turbines degrades considerably in hot days of summer. The use of the inlet air cooling system to eliminate this problem is rapidly increasing. One of the effective methods is cooling the inlet air to the compressor by Evaporative Coolers. The purpose of this paper is to study the effects of the evaporative inlet air cooling system on the performance of a heat recovery boiler in a combined cycle power plant. The heat and mass balance of a typical HRSG and its components including the superheaters, evaporators and economizers were calculated. To analyze the effects of the changes in ambient temperature and the flue gas flow, a numerical software has been used. The results have shown that using the evaporative cooler will increase the flue gas mass flow rate to the HRSG. Nevertheless, the exhaust gas temperature control system holds this temperature almost constant. Also, the results show that the produced steam temperature remains almost constant. However, the steam mass flow rate increases. Therefore the output power of the steam turbine of the combined cycle will increase. The effect of the increase in the humidity ratio is shown to be insignificant. In fact, it has negligible effect on the produced steam flow rate and the sulfuric acid dew point.

scholarly journals A Numerical Analysis of the Air-Cooling System of a Spark Ignition Aeronautical Engine

2020 ◽  
Vol 197 ◽  
pp. 06003
Author(s):  
Maria Faruoli ◽  
Annarita Viggiano ◽  
Paolo Caso ◽  
Vinicio Magi
Keyword(s):  
Heat Transfer ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Cooling System ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Air Cooling ◽  
Air Mass ◽  
Air Cooling System

It is well known that spark ignition internal combustion engines for aeronautical applications operate within a specific temperature range to avoid structural damages, detonations and loss of efficiency of the combustion process. An accurate assessment of the cooling system performance is a crucial aspect in order to guarantee broad operating conditions of the engine. In this framework, the use of a Conjugate Heat Transfer method is a proper choice, since it allows to estimate both the heat fluxes between the engine walls and the cooling air and the temperature distribution along the outer wall surfaces of the engine, and to perform parametric analyses by varying the engine operating conditions. In this work, the air-cooling system of a 4-cylinder spark ignition engine, designed by CMD Engine Company for aeronautical applications, is analysed in order to evaluate the amount of the air mass flow rate to guarantee the heat transfer under full load operating conditions. A preliminary validation of the model is performed by comparing the results with available experimental data. A parametric study is also performed to assess the influence of the controlling parameters on the cooling system efficiency. This study is carried out by varying the inlet air mass flow rate from 1.0 kg/s to 1.5 kg/s and the temperature of the inner wall surfaces of the engine combustion chambers from 390 K to 430 K.

scholarly journals Estimation of condensate mass flow rate during purging time in heat recovery steam generator of combined cycle power plant

2014 ◽  
Vol 18 (4) ◽  
pp. 1389-1397 ◽  
Author(s):  
M.A. Ehyaei
Keyword(s):  
Mass Flow Rate ◽  
Steam Generator ◽  
Mass Flow ◽  
Flow Rate ◽  
Heat Recovery ◽  
Steam Pressure ◽  
Combined Cycle ◽  
Heat Recovery Steam Generator ◽  
Gas Temperature ◽  
Condensate Formation

In this paper the transient modeling of HRSG (Heat recovery steam generator) in purging time was considered. In purging time, compressed air from the gas turbine was used to purge a combustible gas from HRSG. During this time; steam condensate was formed in the superheater stage which should be drained completely to avoid some problems such as deformation of superheaters. Because of this reason, estimation of drain formation is essential to avoid this problem. In this paper an energy model was provided and this model was solved by MATLsoftware. Average model error is about 5%. Results show that, during purge time, steam temperature was decreased from 502 (?C) (Superheater 2), 392 (?C) (Superheater1) and 266 (?C) (Evaporators 1&2) to 130 (?C), 130 (?C) and 220 (?C), respectively and also steam pressure was decreased from 52 (bar) to 23(bar) during purge time. At end of purge time, condensate formation was about 220 (l) when inlet gas temperature was equal to 100 (?C) and purge gas mass flow rate was equal to 386.86 (kg/s).

Heat Transfer Characteristics of a Rotor-Stator System With Small Radial Outflow

2012 ◽  
Author(s):  
Li Lin ◽  
Jing Ren ◽  
Hongde Jiang ◽  
Peter Childs
Keyword(s):  
Heat Transfer ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Cooling System ◽  
Small Mass ◽  
Eckert Number ◽  
Air Cooling ◽  
Air Cooling System ◽  
Radial Outflow

In some cases, the mass flow rate needed to prevent ingress through rim seals in turbine is smaller than that entrained by a free disk. In order to obtain the heat transfer features of the rotor-stator system at such a small mass flow rate, a combined computational and theoretical study has been carried out. It is found that the average Nusselt number (Nuav) on the rotor drops approximately linearly down to zero with decreasing turbulent flow parameter (λt) when λt is smaller than λt,c (λt,c < λt,fd), while Nuav almost keeps constant when λt is larger than λt,c. A correlation between Nuav and λt has been developed, which is expected to be useful in determining disk temperatures in the preliminary design of an internal air cooling system. The Eckert number, which can express the relationship between heat generated by windage and heat conducted through disk, turns out to be an important nondimensional number in describing the heat transfer features of such rotor-stator systems. Moreover, the effect of rotational speed on heat transfer when λt,c<λt<λt,fd has been studied, further identifying the significance of the Eckert number.

Gas Turbine Power Augmentation Using Fog Inlet Air-Cooling System

Volume 1 ◽  
2004 ◽  
Author(s):  
Mohammad Ameri ◽  
Hamid Nabati ◽  
Alireza Keshtgar
Keyword(s):  
Power Plant ◽  
Gas Turbine ◽  
Mass Flow Rate ◽  
Air Temperature ◽  
Flow Rate ◽  
Power Output ◽  
Gas Turbines ◽  
Cooling System ◽  
Air Cooling ◽  
Air Cooling System

Gas turbines are almost constant volume machines at a specific rotating speed, i.e., air intake is limited to a nearly fixed volume of air regardless of ambient air conditions. As air temperature rises, its density falls. Thus, although the volumetric flow rate remains constant, the mass flow rate is reduced as air temperature rises. Power output is also reduced as air temperature rises because power output is proportional to mass flow rate. This power output reduction is from 0.5% to 0.9% of the ISO output power for every 1°C rise in the ambient temperature. The solution of this problem is very important because the peak demand season also happens in the summer. One of the useful methods to overcome this problem is to apply the fog inlet air cooling system for the gas turbines. In this paper the Rey Power Plant site climate conditions in the summer have been studied. The design conditions regarding the dry bulb temperature and relative humidity have been selected. The different inlet air cooling systems have been studied and the Fog system has been chosen. The economical study has shown that this system is very cheap in comparison with the installation of the new gas turbines. The capital cost is estimated to be 40 $/KW. The pay back period is around 1.5 year. The testing of this system has shown that the average power capacity of the power plant is increased by 19 MW and prevented the installation of a new gas turbine.

scholarly journals Cooling Performance Enhancement of Air-Cooled Condensers by Guiding Air Flow

Energies ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 3503
Author(s):  
Huang ◽  
Chen ◽  
Yang ◽  
Du ◽  
Yang
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Heat Dissipation ◽  
Performance Enhancement ◽  
Cooling System ◽  
Wind Effects ◽  
Cooling Performance ◽  
Air Cooled Condensers ◽  
Arc Shape

Adverse wind effects on the thermo-flow performances of air-cooled condensers (ACCs) can be effectively restrained by wind-proof devices, such as air deflectors. Based on a 2 × 300 MW coal-fired power generation unit, two types (plane and arc) of air deflectors were installed beneath the peripheral fans to improve the ACC’s cooling performance. With and without air deflectors, the air velocity, temperature, and pressure fields near the ACCs were simulated and analyzed in various windy conditions. The total air mass flow rate and unit back pressure were calculated and compared. The results show that, with the guidance of deflectors, reverse flows are obviously suppressed in the upwind condenser cells under windy conditions, which is conducive to an increased mass flow rate and heat dissipation and, subsequently, introduces a favorable thermo-flow performance of the cooling system. When the wind speed increases, the leading flow effect of the air deflectors improves, and improvements in the ACC’s performance in the wind directions of 45° and –45° are more satisfactory. However, hot plume recirculation may impede performance when the wind direction is 0°. For all cases, air deflectors in an arc shape are recommended to restrain the disadvantageous wind effects.

scholarly journals Performance investigation of a volute porous tongue of a turbocharger turbine

2020 ◽  
Vol 40 (1) ◽  
pp. 59-66
Author(s):  
Abderrahmane Chachoua ◽  
Mohamed Kamal Hamidou ◽  
Mohammed Hamel
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Gas Turbines ◽  
Stokes Equations ◽  
Navier Stokes ◽  
Recirculation Flow ◽  
Recirculating Flow ◽  
Show Evidence ◽  
The Right

The design for better performance of the spiral housing volute used commonly in radial and mixed inflow gas turbines is of prime importance as it affects the machine stage at both design and off design conditions. The tongue of the scroll divides the flow into two streams, and represents a severe source of disturbances, in terms of thermodynamic parameter uniformity, maximum kinetic energy, the right angle of attack to the rotor and minimum losses. Besides, the volute suffers an undesirable effect due to the recirculating mass flow rate in near bottom vicinity of the tongue. The present project is an attempt to design a tongue fitted with cylindrical holes traversing normal to the stream wise direction, where on account of the large pressure difference between the top and the bottom sides of the tongue will force the recirculating flow to go through the rotor inlet. This possibility with its limitations has not yet been explored. A numerical simulation is performed which might provide our suitable objectives. To achieve this goal the ANSYS code is used to build the geometry, generate the mesh, and to simulate the flow by solving numerically the averaged Navier Stokes equations. Apparently, the numerical results show evidence of favorable impact in using porous tongue. The realization of a contact between the main and recirculation flow by drilled holes on the tongue surface leads to a flow field uniformity, a reduction in the magnitude of the loss coefficient, and a 20 % reduction in the recirculating mass flow rate.

Design and Testing of a Can Combustor for a Small Gas Turbine Application

2013 ◽  
Author(s):  
K. V. L. Narayana Rao ◽  
N. Ravi Kumar ◽  
G. Ramesha ◽  
M. Devathathan
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Gas Turbines ◽  
Pressure Loss ◽  
High Energy ◽  
Experimental Results ◽  
High Mass ◽  
Test Facility ◽  
Design Requirements

Can type combustors are robust, with ease of design, manufacturing and testing. They are extensively used in industrial gas turbines and aero engines. This paper is mainly based on the work carried out in designing and testing a can type combustion chamber which is operated using JET-A1 fuel. Based on the design requirements, the combustor is designed, fabricated and tested. The experimental results are analysed and compared with the design requirements. The basic dimensions of the combustor, like casing diameter, liner diameter, liner length and liner hole distribution are estimated through a proprietary developed code. An axial flow air swirler with 8 vanes and vane angle of 45 degree is designed to create a re-circulation zone for stabilizing the flame. The Monarch 4.0 GPH fuel nozzle with a cone angle of 80 degree is used. The igniter used is a high energy igniter with ignition energy of 2J and 60 sparks per minute. The combustor is modelled, meshed and analysed using the commercially available ansys-cfx code. The geometry of the combustor is modified iteratively based on the CFD results to meet the design requirements such as pressure loss and pattern factor. The combustor is fabricated using Ni-75 sheet of 1 mm thickness. A small combustor test facility is established. The combustor rig is tested for 50 Hours. The experimental results showed a blow-out phenomenon while the mass flow rate through the combustor is increased beyond a limit. Further through CFD analysis one of the cause for early blow out is identified to be a high mass flow rate through the swirler. The swirler area is partially blocked and many configurations are analysed. The optimum configuration is selected based on the flame position in the primary zone. The change in swirler area is implemented in the test model and further testing is carried out. The experimental results showed that the blow-out limit of the combustor is increased to a good extent. Hence the effect of swirler flow rate on recirculation zone length and flame blow out is also studied and presented. The experimental results showed that the pressure loss and pattern factor are in agreement with the design requirements.

Cylindrical Parabolic Trough Concentrator and Solar Tower Comparison in an Integrated Solar Combined Cycle Power Plant

2019 ◽  
Author(s):  
Héctor J. Bravo ◽  
José C. Ramos ◽  
César Celis
Keyword(s):  
Power Plant ◽  
Ambient Temperature ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Combined Cycle ◽  
Parabolic Trough ◽  
Combined Cycle Power Plant ◽  
Design Point ◽  
Concentrated Solar Energy

Abstract The intermittency of renewable energies continues to be a limitation for their more widespread application because their large-scale storage is not yet practical. Concentrating solar power (CSP) has the possibility of thermally storing this energy to be used in times of higher demand at a more feasible storage price. The number of concentrated solar energy related projects have grown rapidly in recent years due to the advances in the associated solar technology. Some of the remaining issues regarding the associated high investment costs can be solved by integrating the solar potential into fossil fuel generation plants. An integrated solar combined cycle system (ISCCS) tends to be less dependent to climatic conditions and needs less capital inversion than a CSP system, letting the plant be more reliable and more economically feasible. In this work thus, two technologies of solar concentration (i) parabolic trough cylinder (PTC) and (ii) solar tower (ST) are initially integrated into a three-pressure levels combined cycle power plant. The proposed models are then modeled, simulated and properly assessed. Design and off design point computations are carried out taking into account local environmental conditions such as ambient temperature and direct solar radiation (DNI). The 8760 hourly-basis simulations carried out allow comparing the thermal and economic performance of the different power plant configurations accounted for in this work. The results show that injecting energy into the cycle at high temperatures does not necessarily imply a high power plant performance. In the studied plant configurations, introducing the solar generated steam mass flow rate at the evaporator outlet is slightly more efficient than introducing it at cycle points where temperatures are higher. At design point conditions thus, the plant configuration where the referred steam mass flow rate is introduced at the evaporator outlet generates 0.42% more power than those in which the steam is injected at higher cycle temperatures. At off design point conditions this value is reduced to 0.37%. The results also show that the months with high DNI values and those with low mean ambient temperatures are not necessarily the months which lead to the highest power outputs. In fact a balance between these two parameters, DNI and ambient temperature, leads to an operating condition where the power output is the highest. All plant configurations analyzed here are economically feasible, even so PTC related technologies tend to be more economically feasible than ST ones due to their lower investment costs.

Combined Cycle Plants With Frame 9F Gas Turbines

1991 ◽  
Vol 113 (4) ◽  
pp. 475-481 ◽  
Author(s):  
P. Lugand ◽  
C. Parietti
Keyword(s):  
Power Generation ◽  
Flue Gas ◽  
Gas Turbines ◽  
Heat Recovery ◽  
Catalytic Reduction ◽  
Pressure Level ◽  
Combined Cycle ◽  
Size Factor ◽  
Nox Emissions ◽  
Steam Generators

The new 200 MW class MS 9001F gas turbines allow combined cycle plants to reach even higher output levels and greater efficiency ratings. Size factor and higher firing temperatures, with a three-pressure level steam reheat cycle, offer plant efficiencies in excess of 53 percent. Heat recovery steam generators have been designed to accommodate catalytic reduction elements limiting flue gas NOx emissions to as low as 10 ppm VD (15 percent O2). A range of steam turbine models covers the different possible configurations. Various arrangements based on the 350 or 650 MW power generation modules can be optimally configured to the requirements of each site.

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