Autothermal Reforming of Diesel Oil for PdCeCrFeCu/Al2O3-Catalyzed Hydrogen Production

Abstract Zero-dimensional two-stage SOFC stacks dynamic model was developed to investigate the effect of operating parameters on stacks performance. The model resolves spatially thermal and thermo-electrochemical behaviour for electrochemical reactions, Catalytic Partial Oxidation and Steam Reforming processes. Design variables and thermo-electrochemical properties were obtained from in-house-fabricated SOFCs carried out by project partners. The completed SOFCs based Combined Heat and Power, CHP, system model was validated by data18 and numerical results obtained at steady-state mode showing its high-fidelity. A parametric study with respect to key operating parameters including changes in fuel utilization, lambda number and current density values was conducted. The global CHP system dynamic response, in term of the current/voltage delivered by two-stage SOFC stacks, under a fixed fuel utilization, has been determined resulting in greater variations in the voltage of a single cell in the first stack in comparison to the corresponding values in the second stack.

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Numerical analysis of a serial connection of two staged SOFC stacks in a CHP system fed by methane using Aspen TECH

Polish Journal of Chemical Technology ◽

10.2478/pjct-2019-0007 ◽

2019 ◽

Vol 21 (1) ◽

pp. 33-43

Author(s):

Paulina Pianko-Oprych ◽

Mateusz Palus

Keyword(s):

Electrical Performance ◽

Fuel Utilization ◽

Optimal Control Strategy ◽

Two Stage ◽

Performance Simulation ◽

Serial Connection ◽

Funded Project ◽

Chp System ◽

Sofc Stacks ◽

Good Agreement

Abstract The objective of the study was to develop a steady-state system model in Aspen TECH using user-defined subroutines to predict the SOFC electrochemical performance. In order to achieve high overall fuel utilization and thus high electrical efficiency, a concept of Combined Heat and Power system with two-stage SOFC stacks of different number of cells was analyzed. The concept of two-stage SOFC stacks based system was developed in the framework of the FP7 EU-funded project STAGE-SOFC. The model was validated against data gathered during the operation of the proof-of-concept showing good agreement with the comparative simulation data. Following model validation, further simulations were performed for different values of fuel utilization to analyze its influence on system electrical performance. Simulation results showed that the concept of two-stage SOFC stacks configuration was viable and reliable. The model can be useful for development the optimal control strategy for system under safe conditions.

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Study on the operating parameters of the 10 kW SOFC-CHP system with syngas

International Journal of Coal Science & Technology ◽

10.1007/s40789-021-00451-3 ◽

2021 ◽

Author(s):

Biao Li ◽

Zewei Lyu ◽

Jianzhong Zhu ◽

Minfang Han ◽

Zaihong Sun

Keyword(s):

High Efficiency ◽

Operating Parameters ◽

System Efficiency ◽

Generation System ◽

Electrical Efficiency ◽

Fuel Ratio ◽

Distributed Power Generation ◽

Preheating Temperature ◽

Power Generation System ◽

Chp System

AbstractSolid oxide fuel cell combined with heat and power (SOFC-CHP) system is a distributed power generation system with low pollution and high efficiency. In this paper, a 10 kW SOFC-CHP system model using syngas was built in Aspen plus. Key operating parameters, such as steam to fuel ratio, stack temperature, reformer temperature, air flow rate, and air preheating temperature, were analyzed. Optimization was conducted based on the simulation results. Results suggest that higher steam to fuel ratio is beneficial to the electrical efficiency, but it might decrease the gross system efficiency. Higher stack and reformer temperatures contribute to the electrical efficiency, and the optimal operating temperatures of stack and reformer when considering the stack degradation are 750 °C and 700 °C, respectively. The air preheating temperature barely affects the electrical efficiency but affects the thermal efficiency and the gross system efficiency, the recommended value is around 600 °C under the reference condition.

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A Small Gas Turbine Plant for Cogeneration of Electricity, Thermal and Cooling Thermal Energy With an Absorption Unit

Volume 3: Heat Transfer; Electric Power; Industrial and Cogeneration ◽

10.1115/97-gt-174 ◽

1997 ◽

Author(s):

Maurizio De Lucia ◽

Carlo Lanfranchi ◽

Antonio Matucci

Keyword(s):

Gas Turbine ◽

Thermal Energy ◽

Operating Conditions ◽

Hot Water ◽

Plant Performance ◽

Cooling Power ◽

Operating Parameters ◽

The European Union ◽

Cogeneration Plant ◽

Two Stage

A cogeneration plant with a small gas turbine was installed in a pharmaceutical factory and instrumented for acquiring all the values necessary to appraise both its energetic and cost advantages. The plant was designed and built as a demonstrative project under a program for energy use improvement in industry, partially financed by the European Union. The system comprises as its main components: 1) a gas turbine cogeneration plant for production of power and thermal energy under the form of hot water, superheated water, and steam; 2) a two-stage absorption unit, fueled by the steam produced in the cogeneration plant, for production of cooling thermal energy. The plant was provided with an automatized control system for the acquisition of plant operating parameters. The large amount of data thus provided made it possible to compare the new plant, under actual operating conditions, with the previously existing cooling power station with compression units, and with a traditional power plant. This comparative analysis was based on measurements of the plant operating parameters over nine months, and made it possible to compare actual plant performance with that expected and ISO values. The analysis results reveal that gas turbine performance is greatly affected by part-load as well as ambient temperature conditions. Two-stage absorber performance, moreover, turned out to decrease sharply and more than expected in off-design operating conditions.

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A COMPARISON OF SELECTED OPERATING PARAMETERS OF THE DIESEL ENGINE FUELLED WITH MIXTURES OF DIESEL OIL OR LIQUID BIO-FUEL AND NATURAL GAS FOR LOW-POWER GENERATORS

Journal of KONES Powertrain and Transport ◽

10.5604/12314005.1138316 ◽

2015 ◽

Vol 19 (4) ◽

pp. 111-116

Author(s):

Grzegorz Boruta ◽

Maciej Imiołek

Keyword(s):

Diesel Engine ◽

Natural Gas ◽

Low Power ◽

Diesel Oil ◽

Operating Parameters ◽

Power Generators

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Development of a Liquid-Fueled, Lean-Premixed Gas Turbine Combustor

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2906743 ◽

1993 ◽

Vol 115 (3) ◽

pp. 554-562 ◽

Cited By ~ 8

Author(s):

L. H. Cowell ◽

K. O. Smith

Keyword(s):

Gas Turbine ◽

Performance Testing ◽

Operating Conditions ◽

Operating Parameters ◽

Nox Emissions ◽

Fuel Injector ◽

Design Variables ◽

Lean Premixed ◽

Annular Combustor ◽

Injector Design

Development of a lean-premixed, liquid-fueled combustor is in progress to achieve ultra-low NOx emissions at typical gas turbine operating conditions. A filming fuel injector design was tested on a bench scale can combustor to evaluate critical design and operating parameters for low-emissions performance. Testing was completed using No. 2 diesel. Key design variables tested include premixing length, swirler angle, injector centerbody diameter, and reduced liner cooling. NOx emissions below 12 ppmv at 9 bar pressure were measured. Corresponding CO levels were 50 ppmv. An optimized injector design was fabricated for testing in a three injector sector of an annular combustor. Operating parameters and test results are discussed in the paper.

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Bandwidth Analysis of a Broadband Amplifier with Two-Stage Matching System Using the Smith Chart

Bulletin of Kalashnikov ISTU ◽

10.22213/2413-1172-2021-3-53-60 ◽

2021 ◽

Vol 24 (3) ◽

pp. 53-60

Author(s):

A.A. Sherstneva

Keyword(s):

Noise Figure ◽

Impedance Matching ◽

Low Noise ◽

Low Noise Amplifiers ◽

Matching Problem ◽

Two Stage ◽

Analysis And Design ◽

Design Variables ◽

Stage Matching ◽

Smith Chart

This paper describes a novel trace structure for the analysis and design of two-stage Broadband Frequency Low Noise Amplifiers based on standard Smith chart procedures and program algorithm realization. The method allows to put the transistor's S-parameters and details of the source and load networks and to interactively explore the effects of these quantities on design variables such as gain, noise figure and stability. It also facilitates the design of two-element matching networks to transform the source and load impedances to optimum values to achieve the desired gain and noise performance. The extended Smith chart concept is proposed to enable the advanced graphical interpretation of devices containing complex properties. This methodology is based on the Smith chart concept, and makes it easy to deal with devices containing signal sources, nonlinearity, very high Q factors and negative resistances. The concept of explaining the use of the Smith chart in combination with using modern tools as MATLAB scripts is exemplified in graphical forms. Phyton-based program contains the algorithm for parameters calculation. It explains the procedure that must be used to solve the two-stage impedance-matching problem. The point of this proposal is using of Smith chart plane for the graphical processing for its application to oscillator analysis. To demonstrate the effective usage of this methodology an interpretation and analysis of the oscillator, especially in terms of gain, noise and stability, are provided. The practical relevance concludes results of multistage design using impedance matching LC networks for the intersection level. The values of the parameters of the integrated microcircuit confirm the possibility of using the calculation methodology considered in the paper. The proposed solution is validated with extensive RF measurements at 3.5 GHz and is benchmarked against several frequency ranges for noise, stability and gain values. The methodology shown in the paper can be used in the development and design of modern microwave amplifiers, as well as for research and analysis of the efficiency of existing devices.

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Practical Optimal Design on Two Stage Spur Gears Train Using Nature Inspired Algorithms

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.f8638.088619 ◽

2019 ◽

Vol 8 (6) ◽

pp. 4073-4081

Keyword(s):

Power Transmission ◽

Spur Gear ◽

Contact Ratio ◽

Two Stage ◽

Gear Drive ◽

Mechanical Constraints ◽

Design Variables ◽

Accurate Design ◽

Power Transmission Systems ◽

Nature Inspired Algorithms

The accurate design of spur gear drive has a tremendous impact on size, weight, transmission and machine performance. Also, the demand for lighter gears is high in power transmission systems, as they save material and energy. Hence this paper presents an enhanced method to solve a two stage spur gear optimization problem. It consists of a mathematical model with a nonlinear objective function and 11 constraints. A two stage spur gear is considered. To obtain minimum volume of spur gear drive is objective of the problem. The considered design variables are: Module, number of teeth, base width of the gears and, shaft diameter and power. Besides considering regular mechanical constraints based on American Gear Manufacturers Association (AGMA) requisites, six more additional critical constraints on contact ratio, load carrying capacity, power loss, root not cut, no involute interference and line of action are imposed on the drive. Nature inspired optimization algorithms, namely, Simulated Annealing (SA), Firefly (FA) and MATLAB solver fmincon are used to find solution in MATLAB environment. Simulation results are analyzed, compared with literature and validated

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