A Universal Mathematical Model for a New Combined-Cycle, Fossil-Fuel Power System (LAJ Cycle): Part 2 — Dynamic Model

2002 ◽  
Author(s):  
Roddie R. Judkins ◽  
Timothy R. Armstrong ◽  
Solomon D. Labinov
Keyword(s):  
Mathematical Model ◽  
Power System ◽  
Dynamic Model ◽  
Fossil Fuel ◽  
Dynamic Models ◽  
Combined Cycle ◽  
Transition Time ◽  
Entire System ◽  
Partial Load ◽  
System Components

A Universal Mathematical Model (UMM) has been developed and applied to a combined-cycle, fossil-fuel power system. The UMM includes static and dynamic models of the system. The static model allows for thermodynamic and thermochemical analyses of the basic system components (reformer, turbine, membrane separator, fuel cell, air compressor, heat exchanger, and other components) and the entire system. The dynamic model provides for mode-to-mode (a partial load to a full or nominal load) time determination for the individual system components and for the entire system. System transient modes were studied, and it was determined that the reforming reactor transition time should be no less than 200 sec, which results in a system mode-to-mode transition time of three to four minutes.

A Universal Mathematical Model for a New Combined-Cycle, Fossil-Fuel Power System (LAJ Cycle): Part 1 — Static Model

2002 ◽  
Author(s):  
Roddie R. Judkins ◽  
Timothy R. Armstrong ◽  
Solomon D. Labinov
Keyword(s):  
Mathematical Model ◽  
Power System ◽  
Methane Conversion ◽  
Fossil Fuel ◽  
Dynamic Models ◽  
Static Model ◽  
Combined Cycle ◽  
Model Parameters ◽  
Lagrangian Multiplier ◽  
Molar Ratios

A universal mathematical model (UMM) has been developed and applied to the LAJ (for Labinov, Armstrong, and Judkins) cycle, a new combined-cycle, fossil-fuel power system. The UMM includes static and dynamic models of the system. The static model allows for thermodynamic and thermochemical analyses of the basic system components (reformer, turbine, membrane separator, fuel cell, air compressor, heat exchanger, and other components) and the entire system. Equilibrium compositions of reforming products are defined by minimizing Gibbs free energy of the mixtures using the Lagrangian multiplier method. The dependence of the main system parameters on pressure (P), temperature (T), and water-to-methane molar ratios (N) at the steam reformer have been evaluated. For selected reforming parameters, viz., P = 4.0 MPa and T = 1200 K, the degree of methane conversion is near 95% with N = 5. However, in view of mass and size limitations on equipment, a lower value of N = 3 is preferred, in which case the degree of methane conversion is 88%. The dependence of the system static model parameters on N has been investigated, and economic characteristics of the model have been evaluated for an output power of 250 kW. It is shown that when, N = 3, the fuel cost contribution to overall electricity costs is 1 cent/kWh.

Mathematical Model of Pressure and Flow Distribution on Fluorine Production Lines

2015 ◽  
Vol 1084 ◽  
pp. 678-683
Author(s):  
Oleg P. Savitsky ◽  
Valeriy F. Dyadik ◽  
Oksana P. Kabrysheva
Keyword(s):  
Mathematical Model ◽  
Dynamic Model ◽  
Dynamic Models ◽  
Flow Distribution ◽  
Hydrodynamic Regime ◽  
Technological Scheme ◽  
Control Algorithms ◽  
Production Lines ◽  
Methods Of Synthesis ◽  
Effective Use

This paper is devoted to one of the most urgent problems in the automation of fluorine production (FP) processes: the development of a dynamic model of the hydrodynamic regime. The paper suggests a dynamic model represented in the form that provides the effective use of up-to-date methods of synthesis and analysis for control algorithms. The model is a set of dynamic models of individual units and devices that have a significant impact on the processes in the technological scheme.

The LAJ Cycle: A New Combined-Cycle Fossil Fuel Power System

2002 ◽  
Author(s):  
Roddie R. Judkins ◽  
Timothy R. Armstrong ◽  
Solomon D. Labinov
Keyword(s):  
Fuel Cells ◽  
Natural Gas ◽  
Power System ◽  
Fossil Fuel ◽  
High Efficiency ◽  
National Laboratory ◽  
Combined Cycle ◽  
Mitigation Strategies ◽  
Model Calculations ◽  
Oak Ridge

Oak Ridge National Laboratory (ORNL) has developed a novel system for combined-cycle power generation, called the LAJ cycle. This system could serve as a basis for the development of a new generation of high-efficiency combined cycles. In one of several possible configurations of the new combined-cycle fossil fuel power system, natural gas enters the system at 4.0 MPa and about 300 K, is heated and reformed, and is transferred to a turbine at 4.0 MPa and 1200 K. The gas expands in the turbine to 0.6 MPa and 800 K, and then flows successively to heat exchangers and a condenser-separator, after which it is separated into two gas streams, one containing principally CO with some CH4 and water vapor and the other containing pure H2. The CO and H2 flow to separate fuel cells and undergo electrochemical oxidation with the concomitant production of electricity. Separate streams of water and carbon dioxide (CO2) are produced, making this cycle compatible with carbon mitigation strategies based on sequestration. Model calculations indicate combined-cycle efficiencies greater than 70% based on the lower heating value of natural gas. The high efficiencies realized result from a combination of the high-pressure natural gas reformate expansion and the highly efficient CO and H2 fuel cells. Most of the power derives from the fuel cells in the system.

scholarly journals The SIR dynamic model of infectious disease transmission and its analogy with chemical kinetics

2020 ◽  
Author(s):  
Cory Simon
Keyword(s):  
Infectious Disease ◽  
Mathematical Model ◽  
Dynamic Model ◽  
Chemical Kinetics ◽  
Disease Transmission ◽  
Dynamic Models ◽  
Catalyst Deactivation ◽  
Batch Reactor ◽  
Mitigation Strategies ◽  
Infectious Disease Transmission

The classic Susceptible-Infectious-Recovered (SIR) mathematical model of the dynamics of infectious disease transmission resembles a dynamic model of a batch reactor carrying out an auto-catalytic reaction with catalyst deactivation. By making this analogy between disease transmission and chemical reactions, chemists and chemical engineers can peer into dynamic models of infectious disease transmission used to forecast epidemics and assess mitigation strategies.

Dynamic Model of a Two Shaft Heavy-Duty Gas Turbine With Variable Geometry

1995 ◽  
Author(s):  
Pierluigi Nava ◽  
Valter Quercioli ◽  
Tiziano Mammoli
Keyword(s):  
Dynamic Model ◽  
Gas Turbines ◽  
Dynamic Models ◽  
Stable Operation ◽  
Variable Geometry ◽  
Heavy Duty ◽  
Gas Generator ◽  
Operating Range ◽  
Start Up ◽  
Partial Load

When designing a new plant, often it is necessary to make a simulation of the process in order to evaluate the dynamic behaviour of the whole system and the need of changes for its optimal performance. So dynamic models of the gas turbines used in the plant, either as mechanical drives or power generation, are needed. Actual gas turbines often incorporate variable geometry both in cold and hot sections. For example, the last generation of axial compressors are often equipped with variable geometry stator blades in order to achieve stable operation within the whole operating range, from start-up to full speed. As another example, power turbines sometimes have inlet guide vanes with a variable geometry in order to get a better efficiency at both partial load and speed, allowing the gas generator to run at the design speed. Disregarding to this, dynamic models which can be found in the actual literature deal with hot sections having a fixed geometry. This paper presents a dynamic model of two shaft heavy-duty gas turbines, with variable geometry in either cold and hot sections. It can be used to evaluate all the transient conditions such as start-up, shut-down and load variations in the normal operating range.

scholarly journals Dynamic-Model-Based AGC Frequency Control Simulation Method for Korean Power System

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5052
Author(s):  
Han Na Gwon ◽  
Kyung Soo Kook
Keyword(s):  
Power System ◽  
Dynamic Model ◽  
Dynamic Models ◽  
Frequency Control ◽  
Simulation Method ◽  
Automatic Generation ◽  
Planning Stage ◽  
Frequency Responses ◽  
Model Based ◽  
Control Simulation

To fulfill the need of operating power systems more effectively through diverse resources, frequency control conditions for maintaining a balance between generators and loads need to be provided accurately. As frequency control is generally achieved via the governor responses from local generators and the automatic generation control (AGC) frequency control of the central energy management system, it is important to coordinate these two mechanisms of frequency control efficiently. This paper proposes a dynamic-model-based AGC frequency control simulation method that can be designed and analyzed using the governor responses of generators, which are represented through dynamic models in the planning stage. In the proposed simulation model, the mechanism of the AGC frequency control is implemented based on the dynamic models of the power system, including governors and generators; hence, frequency responses from the governors and AGC can be sequentially simulated to coordinate and operate these two mechanisms efficiently. The effectiveness of the proposed model is verified by simulating the AGC frequency control of the Korean power system and analyzing the coordination effect of the frequency responses from the governors and AGC.

Ensuring the Validity of Methodical Support for Managing Electric Power System Components

2020 ◽  
Vol 2 (2) ◽  
pp. 4-9
Author(s):  
El’mar M. FARKHADZADE ◽  
◽  
Audin Z. MURADALIYEV ◽  
Tamara K. RAFIYEVA ◽  
Aisel’ AliPanach kyzy RUSTAMOVA ◽  
...  
Keyword(s):  
Power System ◽  
Electric Power ◽  
Electric Power System ◽  
System Components
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