scholarly journals Development of simplified mathematical model of P-88 recovery boiler for operating modes at loads near the nominal

Vestnik IGEU ◽  
2021 ◽  
pp. 5-13
Author(s):  
B.L. Shelygin ◽  
S.A. Pankov ◽  
G.V. Ledukhovsky
Keyword(s):  
Mathematical Model ◽  
Power Unit ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Software Systems ◽  
Specialized Software ◽  
Combined Cycle Plant ◽  
Calculation Results ◽  
Recovery Boiler ◽  
Simplified Mathematical Model

To improve the design of the elements of combined-cycle plants, and their structural and mode optimization, mathematical models are required. These models show energy efficiency indicators of the equipment under changing operating conditions. Modeling of recovery boilers is traditionally carried out with the application of specialized software systems that implement submodels of thermal-hydraulic calculations of the elements of the boiler water-steam and gas paths. This approach makes it difficult to solve practical tasks, since it requires licensed software and appropriate qualifications of an engineer. The current direction of solving this problem is statistical processing of the results of calculation data obtained with the application of specialized software systems, and development of a simplified mathematical model in the form of regression dependencies of boiler performance on variable parameters. In this study, the problem is solved in relation to the P-88 boiler of the combined-cycle plant-325 power unit in the load range near the nominal one. The initial mathematical model is developed with the application of the software package “TRAKT” designed for verification and engineering design of boilers. The simplified mathematical model is based on the methods of regression analysis of statistical data. The accuracy of the model is estimated based on the operational data of the combined-cycle plant -325 power unit. The authors have developed the mathematical model of the P-88 recovery boiler, which allows to determine the main performance indicators of the boiler when the electric power of the gas turbine and the outdoor air temperature are changing at the loads near the nominal value. The performance indicators are determined without application of specialized software for design calculation of the boiler. The accuracy of the initial mathematical model implemented in the software package “TRACT” is characterized by deviation of the calculation results data from the operational data in the corresponding modes of no more than 2 %. The additional uncertainty value introduced into the calculation results data does not exceed 1,5 % when we transfer from the initial mathematical model to the simplified one. The resulting mathematical description will allow solving the problems of mode optimization and evaluating the efficiency of the recovery boiler and the power unit under changing operating conditions.

scholarly journals A mathematical model for the virtual simulator of the power unit electrical part

2022 ◽  
Vol 1216 (1) ◽  
pp. 012009
Author(s):  
P Baran ◽  
Y Varetsky ◽  
V Kidyba ◽  
Y Pryshliak
Keyword(s):  
Mathematical Model ◽  
Power Plant ◽  
Differential Equations ◽  
Power System ◽  
Real Time ◽  
Power Unit ◽  
Operating Conditions ◽  
Auxiliary System ◽  
Algebraic Differential Equations ◽  
Electrical Part

Abstract The mathematical model is developed for a virtual training system (simulator) of the power unit electrical part operators of a thermal (nuclear) power plant. The model is used to simulating the main operating conditions of the power unit electrical part: generator idling, generator synchronization with the power system, excitation shifting from the main unit to the backup one and vice versa, switching in the power unit auxiliary system, and others. Furthermore, it has been implemented modelling some probable emergency conditions within a power plant: incomplete phase switching, damage to standard power unit equipment, synchronous oscillations, asynchronous mode, etc. The model of the power unit electrical part consists of two interacting software units: models of power equipment (turbine, generator with excitation systems, auxiliary system) and models of its control systems, automation, relay protection and signalling. The models are represented by the corresponding algebraic-differential equations that provide real-time mapping power unit processes at the operator’s request. The developed model uses optimal solving algebraic-differential equations to ensure the virtual process behaviour in real-time. In particular, the implicit Euler method is used to solve differential equations, which is stable when simulating processes in significant disturbances, such as accidental disconnection of the unit from the power system, tripping and energizing loads, generator excitation loss, etc.

Thermal Performance Prediction of a Biomass Based Integrated Gasification Combined Cycle Plant

2012 ◽  
Vol 134 (2) ◽  
Author(s):  
T. Srinivas ◽  
B. V. Reddy ◽  
A. V. S. S. K. S. Gupta
Keyword(s):  
Co2 Emissions ◽  
Pressure Ratio ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Maximum Efficiency ◽  
Inlet Temperature ◽  
Integrated Gasification Combined Cycle ◽  
Fuel Ratio ◽  
Combined Cycle Plant ◽  
Integrated Gasification

The performance characteristics of a rice husk based integrated gasification combined cycle (IGCC) plant has been developed at the variable operating conditions of gasifier. A thermo-chemical model developed by the authors has been applied for wet fuel (fuel with moisture) for predicting the gas composition, gas generation per kg of fuel, plant efficiency and power generation capacity, and NOx and CO2 emissions. The effect of the relative air fuel ratio (RAFR), steam fuel ratio (SFR), and gasifier pressure has been examined on the plant electrical efficiency, power output, and NOx and CO2 emissions of the plant with and without supplementary firing (SF) between gas turbine (GT) outlet and heat recovery steam generator (HRSG). The optimum working conditions for efficient running of the IGCC plant are 0.25 RAFR, 0.5 SFR, and 11 bar gasifier pressure at the GT inlet temperature of 1200 °C. The optimum operational conditions of the gasifier for maximum efficiency condition are different compared to maximum power condition. The current IGCC plant results 264.5 MW of electric power with the compressor air flow rate of 375 kg/s at the existed conventional combined cycle plant conditions (Srinivas et al., 2011, “Parametric Simulation of Combined Cycle Power Plant: A Case Study,” Int. J. Thermodyn. 14(1), pp. 29–36). The optimum compressor pressure ratio increases with increase in GT inlet temperature and decreases with addition of SF.

scholarly journals Mathematical modelling of the CHP plant-10 power unit No 5 of “Baikal Energy Company” LLC to assess the efficiency of its modernisation

2021 ◽  
Vol 25 (2) ◽  
pp. 183-195
Author(s):  
F. V. Zabuga ◽  
V. E. Alekseyuk
Keyword(s):  
Mathematical Model ◽  
Power Plant ◽  
Mathematical Modelling ◽  
Power Unit ◽  
Low Pressure ◽  
Operating Conditions ◽  
Computer Assisted ◽  
Model Parameters ◽  
Programming System ◽  
Energy Company

The work aims to study the effect of changes in the drain scheme of the low-pressure regeneration on the energy and economic efficiency of the CHP plant-10 power unit No 5 of “Baikal Energy Company” LLC. In this study, we used a mathematical model of the power unit adjusted to the measurements results. The mathematical modelling of the power unit was performed using the “Computer-assisted programming system” application package. The created matematical model of the heat and power plant was tailored to the current state of the study object according to the three-stage identification procedure of the mathematical model parameters. We proposed a cycle arrangement under which three streams of the low-pressure drainages were redirected to the pump suction of the low-pressure heater. The improved mathematical model of the power unit allows the calculation of the parameters of both the existing and proposed cycle arrangements. According to the calculations, the temperature difference between the main condensate after the low-pressure heater 1 and the investigated drains after mixing is minimal and amounts to 3.2 °C. The suggested modernisation increases the energy efficiency of the power unit by 0.007% under the nominal operating conditions of the existing and proposed thermal circuit. In addition, the specific standard fuel consumption for electric generation is reduced by 0.052 g.s.s.f./kWh. The operating costs to implement the proposed engineering solutions amounted to 34,191 roubles. Considering the annual power plant extensive consumption factor, the payback period of the proposed modernisation will be 5.5 months. The savings for the first operation year are estimated at 18,423 roubles, based on the rate of return and depreciation expenses. The proposed approach combines mathematical modelling of operating power plants with a technique of increasing the efficiency of technical decision-making. The proposed versatile approach can be used for the modernisation of CHPs and other plants.

Nuclear Air-Brayton Combined Cycle (NACC) With Natural Gas Peak Power

2013 ◽  
Author(s):  
Charles Forsberg ◽  
Daniel Curtis
Keyword(s):  
High Temperature ◽  
Natural Gas ◽  
Heat Recovery ◽  
Peak Power ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Heat Recovery Boiler ◽  
Coated Particle ◽  
Recovery Boiler ◽  
Base Load

The Fluoride-Salt-Cooled High-Temperature Reactor (FHR) is a new reactor concept that uses the graphite-matrix coated-particle fuel from gas-cooled reactors and a high-temperature liquid salt coolant. The reactor exit temperatures exceed 700°C with reactor inlet temperatures of ∼600°C. Because of these high temperatures the FHR can be coupled to a nuclear air-Brayton combined-cycle (NACC) plant with one or more air-Brayton turbines with hot exhaust directed to a steam recovery boiler. Under normal base-load operating conditions, air is compressed, heated using salt-air heat exchangers, passed through a turbine, and exhausted to a heat recovery boiler, and added electricity is made from the steam that is generated. The NACC can have one or more salt-to-air reheat stages. After air compression and nuclear heating, the hot compressed air is above the auto-ignition temperature of natural gas (NG). Natural gas can be injected to increase gas temperatures and produce peak power. Because the plant operates continuously as a base-load system connected to the grid and there is no need to control the fuel-to-air ratio, the peak power can be varied and increased rapidly. At times of low electricity prices, steam from the heat recovery boiler can be sold to industrial users at lower prices than they can generate it from NG but above its value for electricity generation. The incremental capital cost for peaking capabilities is less than the cost of stand-alone NG plants. There is the potential for the NG-to-electricity efficiencies exceeding those of stand-alone NG plants. These capabilities imply plant revenue 20 to 50% greater than from an equivalent base-load nuclear plant. The market requirements are being assessed to determine the requirements for the FHR and NACC power cycle. As a new-type of plant, much additional work is required to understand the design options and limitations.

Performance and Cost Characteristics of Combined Cycles Integrated With Second Generation Gasification Systems

1980 ◽  
Author(s):  
R. P. Shah ◽  
D. J. Ahner ◽  
G. R. Fox ◽  
M. J. Gluckman
Keyword(s):  
Gas Turbine ◽  
Power Plants ◽  
Fixed Bed ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Performance Trends ◽  
Combined Cycle Plant ◽  
Combined Cycles ◽  
Near Term ◽  
Cost Characteristics

The performance of combined cycle power plants integrated with advanced air- and oxygen-blown entrained gasification systems as well as with advanced oxygen-blown fixed bed gasifiers will be presented. The performance and cost of such plants using near-term gas turbine technology will be compared to the performance of conventional coal-fired steam plants with FGD. The integrated combined cycle plant appears attractive at today’s gas turbine firing temperatures. Further benefits from advanced gas turbine operating conditions on the performance and economics of such plants and the rationale for these performance trends will be discussed.

scholarly journals ENERGY EFFICIENCY OF GEARBOXES APPLICATION IN POWER UNITS OF ELECTRIC VEHICLES

2021 ◽  
Vol 3 (56) ◽  
pp. 5-12
Author(s):  
Sergey N. PODDUBKO ◽  
◽  
Nikolay N. ISHIN ◽  
Arkadiy M. GOMAN ◽  
Andrey S. SKOROKHODOV ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Power Unit ◽  
Electric Vehicles ◽  
Electric Motor ◽  
Hydrocarbon Fuel ◽  
High Energy ◽  
Operating Conditions ◽  
Total Energy Consumption ◽  
Calculation Results

With all advantages, electric vehicles have a significant disadvantage — a relatively small driving range on a single charge of the traction battery compared to cars using hydrocarbon fuel. The solution to the issue is to choose a rational structural scheme of an electromechanical power unit to obtain its high energy efficiency regardless of the operating conditions. A significant number of electric vehicles produced today either do not contain gearboxes or contain single-speed reducers. The use of a multi-speed gearbox solves the problem of adapting the working processes of a traction electric motor to the loading conditions, bringing its efficiency as close as possible to the range of highly efficient values. Calculated estimation of energy consumption of the MAZ-4381EE electric delivery truck is carried out in the paper for various versions of the mechanical part of power unit: without a reducer, with the use of a reducer and two types of two-speed gearboxes (shaft and shaft-planetary). The evaluation is made based on consideration of the European test driving cycle NEDC, taking into account the use of efficiency maps of the traction induction electric motor. The calculation results showed that the use of two-speed gearboxes can reduce the total energy consumption by more than 1.8 times compared to a power unit with a high-torque motor and without a gearbox.

scholarly journals Validation of a Simulation Model for a Combined Otto and Stirling Cycle Power Plant

2010 ◽  
Author(s):  
Jim McGovern ◽  
Barry Cullen ◽  
Michel Feidt ◽  
Stoian Petrescu
Keyword(s):  
Computer Simulation ◽  
Power Plant ◽  
Simulation Model ◽  
Combined Cycle ◽  
Optimization Techniques ◽  
Operating Conditions ◽  
Computer Simulation Model ◽  
Stirling Cycle ◽  
Wide Range ◽  
Combined Cycle Plant

A project has been underway at the Dublin Institute of Technology (DIT) to investigate the feasibility of a combined Otto and Stirling cycle power plant in which a Stirling cycle engine would serve as a bottoming cycle for a stationary Otto cycle engine. This type of combined cycle plant is considered to have good potential for industrial use. This paper describes work by DIT and collaborators to validate a computer simulation model of the combined cycle plant. In investigating the feasibility of the type of combined cycle that is proposed there are a range of practical realities to be faced and addressed. Reliable performance data for the component engines are required over a wide range of operating conditions, but there are practical difficulties in accessing such data. A simulation model is required that is sufficiently detailed to represent all important performance aspects and that is capable of being validated. Thermodynamicists currently employ a diverse range of modeling, analysis and optimization techniques for the component engines and the combined cycle. These techniques include traditional component and process simulation, exergy analysis, entropy generation minimization, exergoeconomics, finite time thermodynamics and finite dimensional optimization thermodynamics methodology (FDOT). In the context outlined, the purpose of the present paper is to come up with a practical validation of a practical computer simulation model of the proposed combined Otto and Stirling Cycle Power Plant.

Sign in / Sign up

Export Citation Format

Share Document