Models for Simulation and Diagnosis of Energy Plant Components

Author(s):  
Giovanni Cerri ◽  
Sandra Borghetti ◽  
Coriolano Salvini

This paper describes a methodology to set up models for simulation and diagnosis of energy plant components. The adopted approach consists in a simultaneous solution of modules representing plant components taking their actual behavior into account. Models are characterized by Reality Functions to adapt them to the reality of machines and apparatuses so that the New&Clean map of the real component can be established. Furthermore, to account for deterioration phenomena occurring during plant operations, Actuality Functions affecting component performance in terms of work and heat transfer, losses and effective flow functions have been introduced. Models have been validated and tested against real CHP plant data. Two applications to different kinds of power plants are presented and discussed. Results show a good capability to estimate component deterioration statuses and reproduce component actual behavior maps.

Author(s):  
Giovanni Cerri ◽  
Stefano Mazzoni ◽  
Coriolano Salvini

This paper describes a methodology to set up steam cycle simulators for CHP plants. The adopted approach consists in a simultaneous solution of modules representing plant components taking their actual behavior into account. Models are characterized by Reality Functions to adapt them to the reality of machines and apparatuses so that the New&Clean map of the real component can be established. Furthermore, to account for deterioration phenomena occurring during plant operations, Actuality Functions affecting component performance in terms of work and heat transfer, losses and effective flow functions have been introduced. Models have been validated and tested against real CHP plant data. Applications to different kinds of CHP steam cycles are presented and discussed. Results show a good simulator capability to estimate component deterioration status and to reproduce the plant actual behavior.


2019 ◽  
Vol 7 (2B) ◽  
Author(s):  
Vanderley Vasconcelos ◽  
Wellington Antonio Soares ◽  
Raissa Oliveira Marques ◽  
Silvério Ferreira Silva Jr ◽  
Amanda Laureano Raso

Non-destructive inspection (NDI) is one of the key elements in ensuring quality of engineering systems and their safe use. This inspection is a very complex task, during which the inspectors have to rely on their sensory, perceptual, cognitive, and motor skills. It requires high vigilance once it is often carried out on large components, over a long period of time, and in hostile environments and restriction of workplace. A successful NDI requires careful planning, choice of appropriate NDI methods and inspection procedures, as well as qualified and trained inspection personnel. A failure of NDI to detect critical defects in safety-related components of nuclear power plants, for instance, may lead to catastrophic consequences for workers, public and environment. Therefore, ensuring that NDI is reliable and capable of detecting all critical defects is of utmost importance. Despite increased use of automation in NDI, human inspectors, and thus human factors, still play an important role in NDI reliability. Human reliability is the probability of humans conducting specific tasks with satisfactory performance. Many techniques are suitable for modeling and analyzing human reliability in NDI of nuclear power plant components, such as FMEA (Failure Modes and Effects Analysis) and THERP (Technique for Human Error Rate Prediction). An example by using qualitative and quantitative assessesments with these two techniques to improve typical NDI of pipe segments of a core cooling system of a nuclear power plant, through acting on human factors issues, is presented.


Author(s):  
Nickolas J. Themelis

This report presents the results of a study that examined alternatives to landfilling the municipal solid wastes (MSW) of New York City. Detailed characterization of the wastes led to their classification, according to materials properties and inherent value, to “recyclable”, “compostable”, “combustible”, and “landfillable”. The results showed that the present rates of recycling (16.6%) and combustion (12.4%) in New York City can be increased by a) implementing an automated, modern Materials Recovery Facility (MRF) that separates the blue bag stream to “recyclables” and “combustibles”, and b) combusting the non-recyclable materials in a Waste-to-Energy (WTE) facility. Combustion of wastes to produce electricity is environmentally much preferable to landfilling. An advanced technology for combustion is that used in a modern Waste-to-Energy plant (SEMASS, Massachusetts) that processes 0.9 million metric tons of MSW per year, generates a net of 610 kWh per metric ton of MSW, recovers ferrous and non-ferrous metals, and has lower emissions than many coal-fired power plants.


2020 ◽  
Author(s):  
Evrim Oyguc ◽  
Abdul Hayır ◽  
Resat Oyguc

Increasing energy demand urge the developing countries to consider different types of energy sources. Owing the fact that the energy production capacity of renewable energy sources is lower than a nuclear power plant, developed countries like US, France, Japan, Russia and China lead to construct nuclear power plants. These countries compensate 80% of their energy need from nuclear power plants. Further, they periodically conduct tests in order to assess the safety of the existing nuclear power plants by applying impact type loads to the structures. In this study, a sample third-generation nuclear reactor building has been selected to assess its seismic behavior and to observe the crack propagations of the prestressed outer containment. First, a 3D model has been set up using ABAQUS finite element program. Afterwards, modal analysis is conducted to determine the mode shapes. Nonlinear dynamic time history analyses are then followed using an artificial strong ground motion which is compatible with the mean design spectrum of the previously selected ground motions that are scaled to Eurocode 8 Soil type B design spectrum. Results of the conducted nonlinear dynamic analyses are considered in terms of stress distributions and crack propagations.


Author(s):  
Congjian Wang ◽  
Diego Mandelli ◽  
Shawn St Germain ◽  
Curtis Smith ◽  
David Morton ◽  
...  

Abstract As commercial nuclear power plants (NPPs) pursue extended plant operations in the form of Second License Renewals (SLRs), opportunities exist for these plants to provide capital investments to ensure long-term, safe, and economic performance. Several utilities have already announced their intention to pursue extended operations for one or more of their NPPs via SLR2. The goal of this research is to develop a risk-informed approach to evaluate and prioritize plant capital investments made in preparation for, and during the period of, extended plant operations to support decisions in NPP operations. In order to prioritize project selection via a risk-informed approach we developed a single decision-making tool that integrates safety/reliability, cost, and stochastic optimization models to provide users with data analysis capabilities to more cost effectively manage plant assets. Both stochastic analysis methods — such as Monte Carlo-based sampling strategies — and multi-stage stochastic optimization strategies are employed to provide priority lists to decision-makers in support of risk-informed decisions. We applied the proposed method to a trial application of projected replacement/refurbishment expenditures for plant capital assets (i.e., structures, systems, and components [SSCs]). The objective is to optimize the SSC replacement/refurbishment schedule in terms of economic constraints, data uncertainties, and SSC reliability data, as well to generate a priority list for maximizing returns on investment.


Author(s):  
A. de Sam Lazaro ◽  
W. Steffenhagan

Abstract The automation of the control to a power plant is indeed a challenge mainly because of the occurrences of random and unpredictable variations in output demands as well as because of highly non-linear behavior of the system itself [1]. It is sometimes argued that the ‘best’ control for a power plant is the operators themselves. Experienced operators are capable of taking decisions on the basis of incomplete and imprecise information. The extent to which these decisions are correct is a matter of speculation. Erroneous conclusions, established post facto, are chalked up to the learning process and in fact, contribute to the forming of a good, experienced control team. The need to automate the control process for a plant is even more acutely felt when considering the complexity of the plants themselves and the volume of data that would have to be processed before a control decision can be taken. Factored into this decision would also be several governing parameters such as costs, reliability, other constraints and their interdependancy, as well as planned and unscheduled outages for maintenance and so on. In this paper, however, only one facet of a power plant operation is considered. It is intended to demonstrate that thermal efficiency may be improved by better techniques for automated control of throttle valves in the steam turbine of the plant. One of these options, fuzzy logic, is selected, and defended, as being the more effective than current techniques. A comparative analysis is conducted of control techniques for plant operations followed by a brief overview of fuzzy control and its application to control of non-linear systems. A method of applying this ‘new’ computer-based technique to control of non-linear, somewhat erratic plants is presented and discussed.


Author(s):  
Mohammad Mansouri Majoumerd ◽  
Mohsen Assadi ◽  
Peter Breuhaus ◽  
Øystein Arild

The overall goal of the European co-financed H2-IGCC project was to provide and demonstrate technical solutions for highly efficient and reliable gas turbine technology in the next generation of integrated gasification combined cycle (IGCC) power plants with CO2 capture suitable for combusting undiluted H2-rich syngas. This paper aims at providing an overview of the main activities performed in the system analysis working group of the H2-IGCC project. These activities included the modeling and integration of different plant components to establish a baseline IGCC configuration, adjustments and modifications of the baseline configuration to reach the selected IGCC configuration, performance analysis of the selected plant, performing techno-economic assessments and finally benchmarking with competing fossil-based power technologies. In this regard, an extensive literature survey was performed, validated models (components and sub-systems) were used, and inputs from industrial partners were incorporated into the models. Accordingly, different plant components have been integrated considering the practical operation of the plant. Moreover, realistic assumptions have been made to reach realistic techno-economic evaluations. The presented results show that the efficiency of the IGCC plant with CO2 capture is 35.7% (lower heating value basis). The results also confirm that the efficiency is reduced by 11.3 percentage points due to the deployment of CO2 capture in the IGCC plant. The specific capital costs for the IGCC plant with capture are estimated to be 2,901 €/(kW net) and the cost of electricity for such a plant is 90 €/MWh. It is also shown that the natural gas combined cycle without CO2 capture requires the lowest capital investment, while the lowest cost of electricity is related to IGCC plant without CO2 capture.


Author(s):  
V. C. Tandon ◽  
D. A. Moss

Florida Power and Light Company’s Putnam Station, one of the most efficient power plants in the FP&L system, is in a unique and enviable position from an operational viewpoint. Its operation, in the last seven years, has evolved through a triple phase fuel utilization from distillate to residual oil and finally to natural gas. This paper compares the availability/reliability of the Putnam combined cycle station and the starting reliability of the combustion turbines in each of the operating periods. A review of the data shows that high availability/reliability is not fuel selective when appropriate actions are developed and implemented to counteract the detractors. This paper also includes experience with heat rate and power degradation of various power plant components and programs implemented to restore performance.


Author(s):  
M. K. Agrawal ◽  
A. Ravi Kiran ◽  
A. K. Ghosh ◽  
H. S. Kushwaha

The Containment Studies Facility (CSF) is being set up in BARC for studying various containment related thermal hydraulic and other phenomena which occur during simulated accident conditions in Nuclear power Plants. The facility consists of a concrete containment model having a volumetric scale ratio of 200:1 with respect to the actual containment of Indian Pressurized Heavy Water Reactor. The structure is designed for pressure of 1.73 Kg/cm2 for specified leak tightness. Adequacy to withstand design pressure is checked by test as well as numerical analysis before commissioning of the facility. Accordingly Containment building model has been analyzed by finite element method for internal design pressure and dead weight. Analysis has been carried out for the structure with and without the opening in the containment. Effect of opening on the response of containment has been studied. The paper includes the modeling methodology, maximum deflection and stress amplification around the opening for various models.


Author(s):  
Jinquan Yan ◽  
Yinbiao He ◽  
Gang Li ◽  
Hao Yu

The ASME B&PV Code, Section III, is being used as the design acceptance criteria in the construction of China’s third generation AP1000 nuclear power plants. This is the first time that the ASME Code was fully accepted in Chinese nuclear power industry. In the past 6 years, a few improvements of the Code were found to be necessary to satisfy the various requirements originated from these new power plant (NPP) constructions. These improvements are originated from a) the stress-strain curves needed in elastic-plastic analysis, b) the environmental fatigue issue, c) the perplexity generated from the examination requirements after hydrostatic test and d) the safe end welding problems. In this paper, the necessities of these proposed improvements on the ASME B&PV code are further explained and discussed case by case. Hopefully, through these efforts, the near future development direction and assignment of the ASME B&PV-III China International Working Group can be set up.


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