bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Design and Development of an Evaluation System for Redox Characteristics of Anode Supported SOFCs Using In-Situ Acoustic Emission and Electrochemical Technique
Authors: Hashimoto S. , Watanabe H. , Sakamoto T. , Kawada T. , Yashiro K. , Mizusaki J. , Kumada K. , Changsheng D. , Sato K. , Hashida T. 
Published: July 2013

In this study, a redox evaluation system for anode supported SOFCs using in-situ acoustic emission (AE) and electrochemical technique has been developed. The system consists of a gas blending unit, moisture controlling unit, AE cell evaluation probe, gas cooling exhaust, electrochemical cell test system and AE signal measurement system. The anode supported coin cells, which have the same thickness dimension as practical SOFCs have, can be evaluated under temperature and atmosphere controlled conditions. The oxygen partial pressure in the anodic atmospheres can be gradually controlled from air to reducing atmosphere using the gas blending unit which is connected to 6 gas cylinders. Humidity in the anodic atmospheres can be controlled by moisture controlling unit which consists of 2 bubblers form 0.86% (5°C saturation) up to 80% (94°C saturation). Redox process of the anode can be simulated in this system by controlled three oxidation modes, i.e. O2 gas oxidation, steam oxidation and electrochemical oxidation, which correspond to actual troubles, i.e. gas leakage, degradation of downstream and fuel depletion, respectively. An AE transducer can monitor the cell condition via an inner tube for a guide of exhaust from the cathode.
Redox cell test for the anode supported coin cell has been examined at 770°C using this system. After the reduction of the anode substrate in moist H2, current 0.5Acm−2 loaded to the cell. And then H2 gas concentration had been reduced by stages. The cell voltage was down to below −6V after H2 gas concentration was reduced to pH2 = 2%. This drastic cell voltage drop and AE signal generation occurred at the same time. It is considered that Ni re-oxidation with fracture started at this time. Local delamination between anode and electrolyte, and also cracks at the electrolyte and cathode were observed after redox test. It was confirmed that AE sensing is effective for redox evaluation.
High Temperature Oxidation Behaviour of MnCo2O4 Coating on Crofer 22 APU Manufactured by a Novel Solution Precursor Plasma Spray Process (SPPS)
Authors: Puranen Jouni , Laakso Jarmo , Hyvärinen Leo , Kylmälahti Mikko , Vuoristo Petri 
Published: July 2013

MnCo2O4 spinel coatings are designed to be used on metallic interconnectors in SOFC devises to decrease oxidation rate of the metallic interconnect and to prevent the evaporation of harmful CrO3 and Cr2(OH)2 compounds. These Cr-compounds degrade the long-term performance of the SOFC by migrating to the triple phase barrier (TPB) of the cathode and reduce back to Cr2O3. MnCo2O4 spinel coatings, used in this study, were manufactured by using a novel solution precursor plasma spray (SPPS) process and heat treated in oxidizing environment.
Deionized water based solutions of Mn(NO3)2•4H2O and Co(NO3)2•6H2O were used as a feedstock material. Concentration of the metal cations in the solutions was adjusted to 3 M. Ferritic stainless grade Crofer 22 APU with the thickness of 0.5 mm and surface roughness of Ra < 0.5 μm was used as a substrate material. The coatings were manufactured using a Sulzer Metco A3000S plasma spray system with F4-MB plasma gun with modified solution feeding hardware. Coatings with different microstructures were sprayed using different spraying parameters, e.g. the type of plasma gases used. The as-sprayed coatings were aged at 700 °C for 500 h in oxidizing environment, in order to study the stability of the coating, the growth of the Cr-scale and the Cr-transport through the spinel coatings. The microstructural characterization for the as-sprayed and the oxidized coatings were done using a field-emission scanning electron microscopy (FESEM) with SE-mode. The quantitative analyses were executed with energy dispersive spectroscopy (EDS), and in addition X-ray diffraction (XRD) was used for qualitative studies.
The coatings with various microstructures were sprayed. The densest microstructure was sprayed using Ar-He plasma gas. Also the crystallographic equivalence for MnCo2O4 was achieved when Ar-He plasma was used with 40 mm spraying distance. Ageing caused the increase in structural porosity. On the interface between the coating and the interconnect, a dense spinel layer was formed which effectively prevented the Cr-transport forming approximately 500 nm thick Cr-rich sub-scale.
Exergy and Economic Analysis of Catalytic Coal Gasifiers Coupled With Solid Oxide Fuel Cells
Authors: Siefert Nicholas , Litster Shawn 
Published: July 2013

The National Energy Technology Laboratory (NETL) as well as Li et al. [1] have shown that integrating a catalytic coal gasifier with a solid oxide fuel cell (SOFC) can achieve high system efficiencies (∼60%) while capturing and sequestering >90% of the carbon dioxide. Integration of a catalytic gasifier with a SOFC is aided by the minimal exergy destruction inside a catalytic, steam-coal gasifier producing a high-methane content syngas, and the decreased exergy destruction in the SOFC due to the ability to operate at lower air stoichiometric flow ratios compared with a SOFC operating only on hydrogen. For a given temperature difference across the inlet and outlet of the fuel cell and for a given current density, a SOFC can be operated at a lower air stoichiometric ratio if there is a significant amount of methane in syngas and if the pressure of the fuel cell is above atmospheric pressure. Here, we present both an exergy analysis of one possible way of integrating a SOFC with a catalytic gasifier. The gasifier is a fluidized bed gasifier that uses ∼20%wt potassium carbonate along with the coal. Before entering the SOFC, carbon dioxide in the syngas is captured using lime, and then the anode tail gas from the SOFC is recycled back to the gasifier, similar to the configuration modeled by Li et al. [2]. We will present the exergy efficiency as a function of the pressure of the SOFC, and compare the exergy efficiency to other coal-based powerplants on the scale of 100–500 MWe.
In addition, we use capital and other cost estimates from NETL [3] and others [4] to estimate the internal rate of return on investment (IRR) of various coal based fuel cell power plants, and compare the IRR of these plants with other fossil fuel based base load power plants. We also present the IRR of the catalytic gasification-SOFC power plant as a function of the pressure of the SOFC. Assuming recent fuel & electricity prices, a natural gas combined cycle (NGCC) power plant yields the highest value of rate of return on investment. However, our results suggest that, in the case of a CO2 tax near $30/t CO2, then three different configurations are equally viable economically: NGCC, advanced IGCC-CCS-EOR, and advanced IGFC-CCS-EOR that integrates a catalytic coal gasifier with a pressurized SOFC.
Thermal Storage Device for High-Power-Density Systems
Authors: Homitz Joseph , Tucker Brian P. , Messmer Janelle M. 
Published: July 2013

High power levels and high power densities associated with directed energy weapon (DEW) systems, electronic warfare systems, and high thrust-to-weight propulsion systems require the development of effective and efficient thermal management solutions. Among many critical thermal management issues, high peak waste heat generation and limited cooling capacity onboard mobile weapon platforms necessitate the development of advanced thermal storage devices. In addition to storing large amounts of energy in a compact, lightweight package, the devices must be able to store energy rapidly at high power levels.
This paper presents the design of an advanced phase-change thermal storage device developed to meet the requirements of high-power-density systems. Results of experimental performance evaluations are also presented. Based on these evaluations, it is predicted that the device will be able to store an average heat load of up to 2.9 kW/kg over a 20-second period. This thermal storage device is applicable to many different thermal management architectures, is easily adapted to meet the requirements of a wide range of high-power systems, and has potential to significantly reduce thermal management size, weight, and power requirements.
Performance Measurement and Analysis of Vertical Shaft V-Twin Engines, and Comparison With Horizontal Engines of the Same Model Class
Authors: Lemieux Patrick , Moore C. Dennis , Nahab Andrew 
Published: July 2013

Over the past two years, we have conducted two experimental test series aimed at examining typical performance of gasoline V-twin engines in the 25 hp class, and the suitability of assumed mechanical efficiency in correcting observed measurements. We used engines manufactured by Honda, Kawasaki, Kohler, and Subaru (Robin). The tests were conducted at the Engines Laboratory of the California Polytechnic State University, San Luis Obispo (Cal Poly). The Kohler engines are fuel injected while the others three are carbureted. We tested twenty-eight engines in total. The first series of tests included four horizontal shaft engines from each of the manufacturers (sixteen in total), and followed the general guidelines of SAE standard J1349-199506.
This paper reports primarily on the subsequent series of twelve engine tests, which included vertical shaft engines of an equivalent family (and displacement class), from three of the original manufacturers: Honda, Kawasaki and Kohler. All three engines have roughly the same engine speed range (2000–4000), and all three reportedly reach peak power at 3600rpm. This is typical of small engines, which may be used to drive small generators in addition to being installed on other equipment.
Vertical shaft engines are typically tested on a vertical shaft dynamometer, or one that converts from a horizontal to vertical position. However, these dynamometers are typically either of the water brake or eddy current type. They cannot motor the engine, and thus cannot measure friction mean effective pressure (FMEP) directly, which is the preferred method to quantify friction and mechanical efficiency for engine testing. However, testing vertical shaft engines on a horizontal shaft motoring dynamometer requires an angled gear drive to mate the engine to the dynamometer, and thus adds a loss that complicates the accurate measurement of FMEP and brake output. We present here results using a simple method with which our measurements can be corrected for this loss, in tests of this sort.
The study thus expands on our previous results, and shows the extent by which engine to engine variations are affected by shaft configurations, within a given model family, and within similar offerings by different manufacturers. We also analyzed our results to contrast the methodology of SAE J1349-199506 with that of the updated J1349-201109, specifically with respect to using an assumed value of mechanical efficiency to characterize FMEP and correct dynamometer data on small, general utility engines.
Statically Indeterminate Main Bearing Load Calculation in Frequency Domain for Usage in Early Concept Phase
Authors: Parikyan Tigran , Resch Thomas 
Published: July 2013

The paper discusses the importance of a numerical method for fast and accurate prediction of main bearing loads of inner combustion engine and its place in the concept phase of engine development process.
An approach based on linear dynamic analysis of 3D engine model in frequency domain is presented. Implemented within a separate module of AVL software package EXCITE Designer, it delivers a combination of accuracy and performance suitable for this task.
An application example illustrates the method.
Experimental Exhaust Gas Recirculation (EGR) on EMD SD59MX 2.238 Megawatt Diesel-Electric Freight Locomotives
Authors: Iden Michael , Goetzke Michael , Bandyopadhyay Deep 
Published: July 2013

In July 2008, Union Pacific Railroad (UP) and Electro-Motive Diesel, Inc. (EMD) began discussions to jointly investigate the potential for exhaust gas recirculation (EGR) on a small group of re-powered UP locomotives, to assess the potential for EGR as a technology to meet the oxides of nitrogen (NOx) requirement in US Environmental Protection Agency (EPA) Tier 4 locomotive emissions regulations on newly-manufactured future diesel locomotives effective January 1, 2015 [1].
After several years of research, engineering and experimental testing, EMD began delivering to UP in late-2011 nine SD59MX experimental locomotives equipped with prototype EGR technology as a first step to achieving Tier 4 NOx reductions, plus a tenth SD59MX unit equipped with both the EGR technology and an experimental whole-engine aftertreatment package to migrate toward Tier 4 particulate matter (PM) levels on future new Tier 4 locomotives. Compared to today’s Tier 2 emission limits, the EGR equipped SD59MX produces 42 percent less NOx, a significant step toward the development of new Tier 4 locomotives.
Modeling of Film Boiling and Film Vaporization on Engine Piston Tops
Authors: Lee Timothy H. , Kyritsis Dimitrios C. , Lee Chia-fon F. 
Published: July 2013

Engine-out HC emissions resulting from liquid fuel, which escapes from the combustion process, provides the motivation to better understand the film vaporization in a combustion chamber. Previous work theorized that the removal of liquid fuel from the combustion cycle was a result of the increase in film vaporization time due to the Leidenfrost phenomenon. Currently, KIVA 3V predicts a continuous decrease in vaporization time for piston top films. The objective of this work is to improve the KIVA 3V film vaporization model through the inclusion of established boiling correlations, and thus, the Leidenfrost phenomenon.
Experimental results have been reviewed from which expressions encompassing high acceleration effects for the nucleate boiling regime and the film boiling regime were investigated, implemented, and validated. Validation was conducted using published experimental data sets for boiling heat flux. As a result of the implementation, a noticeable increase in heat flux occurred due to high accelerations for films in saturated film boiling in both nucleate and film boiling.
Computational simulations were conducted using a semi-infinite plate and a direct-injection spark-ignition engine. The semi-infinite plate provided a controlled environment which could separate the effects of pressure and acceleration on film boiling heat flux, film vaporization rates, and film vaporization times. The effect of decreased film vaporization rates, during the Leidenfrost phenomenon, was observed to decrease with increasing acceleration. Finally, the engine computations were used to provide the first film boiling and film vaporization rates for engine fuel films at temperatures above saturation temperature. As a result of this work, a film vaporization model capable of improved prediction of vaporization rates of piston top films in saturated boiling conditions has been created.
Investigation of the Optimal Injection Conditions for a PCCI Diesel Engine
Authors: Kim Yungjin , Park Sangki , Lee Kihyung 
Published: July 2013

Premixed charge compression ignition (PCCI) engines have the potential with their attractive advanced combustion process to achieve a more homogeneous mixture and a lower peak combustion temperature resulting in both lower nitrogen oxides (NOx) and diesel particulate matter (PM) emissions. In this study, the spray characteristics for a PCCI engine according to various injection conditions were introduced and then the effects of injection strategies such as injection angles, injection timings and times on combustion and emissions were studied for a single cylinder PCCI engine using early multiple injections first. Add more, a method of early-main type split injection was used for a 4-cylinder PCCI engine and the effects of injection conditions on the combustion and emission characteristics were investigated. Finally flame visualization tests were performed to validate the result obtained from the engine test.
The experimental results showed that the mixture formation, indicated mean effective pressure (IMEP), and emission characteristics were dominantly affected by the injection conditions and the multiple injection method resulted in higher IMEP and still low smoke level characteristics. It appeared that more homogeneous mixture could be formed with decreasing of spray penetration and increasing of fuel evaporation rate for the early multiple injections. In case of the split injection, both injection timing and injected fuel ratio of the early and main injection largely affected engine combustion and emission characteristics. From the results, as the early injection rate increased premixed combustion was activated, on the other hand, as the main injection rate increased conventional diesel combustion was activated, therefore suitable split injection conditions could be selected for the 4-cylinder PCCI engine.
Dynamic Characteristic Analysis and Parameter Estimation for a Thermal Plant
Authors: Miyamoto Yuichi 
Published: July 2013

A thermal plant as a controlled system has many state parameters, which cannot be measured directly in many cases. The control efficiency can be improved by applying estimated parameters to the control of the plant. A fluidized-bed incinerator is not constant in the quantity and quality of the feed refuse, which is the fuel, and combustion control is difficult owing to the rapidity of completion of combustion. However, it is thought to be possible to improve the efficiency of CO control and NOx control drastically if the state parameters such as the combustion rate on the upper bed site and the bed site, and the effective air ratio are known.
This paper proposes a method that estimates these state parameters by means of sensor outputs such as temperature, air flow rate, and cooling water rate, using dynamic characteristic analysis and neural networks. This paper also shows that it is possible to estimate the state parameters of an actual incinerator. Further, it is shown that the generalization of parameters estimation equations enables the application of the method to other plants.
Energy Analysis of Machining and Machining Facilities Based on the Micro-Factory Concept
Authors: Wentz John E. , Coleman Andrew J. 
Published: July 2013

The micro-factory concept has gained wide support and acceptance based on the ability of small machine tools to accomplish the same tasks as traditionally sized machine tools while using a fraction of the space. Although it is frequently mentioned that a micro-factory is an energy saving endeavor, there is a dearth of hard data on how much energy is actually saved.
The intent of this report is to quantify the difference in energy consumed in a micro-factory and a macro-factory though experimentation with a micro- and a macro-mill. This quantification allows for the potential of unit life cycle analyses to be performed in the future. A fluidic channel was machined in workpieces of aluminum and steel by both micro- and macro-mills under a variety of machining conditions and the recorded data has been analyzed to this end. The variables investigated were the spindle speed, the mill type, and the material the cutting process was performed on. The conclusions reached through experimentation were that the micro-mill used between 13.5% and 21.7% of the energy used for the macro-mill.
Additionally the energy differences in climate control were investigated for comparable macro- and micro-factories. The mock macro-factory used for this analysis was three times the size of the micro-factory. Due to the larger size of the macro-building, the climate control energy usages were also about three times as high as in the micro-building.
Approach to Sustainable Smart Town and Role of International Standardization
Authors: Nomura Junji , Morikura Susumu , Tada Shinya 
Published: July 2013

Sustainable Smart Town (SST) scheme which utilizes networking of energy and information is receiving much attention as a way of stable energy supply and efficient operation in each region and country. SST consists of Smart Grid to supply energy efficiently and energy efficient buildings such as smart homes, condominiums, stores and factories. In addition, new service such as Demand Response Service which takes advantage of networking is beginning to appear in the market.
This paper introduces outline of several SST pilot projects, energy consumption reduction in office building, demand response in existing residential house and information security system for facilities. It also mentions the role and future prospect of International Standardization to realize the safe, secure, comfortable and convenient SST.
Adaptive Control of Nonminimum Phase Systems Using Sensor Blending With Application to Launch Vehicle Control
Authors: Balas Mark J. 
Published: July 2013

The goal of this paper is to investigate the use of a very simple direct adaptive controller in the guidance of a large, flexible launch vehicle. The adaptive controller, requiring no on-line information about the plant other than sensor outputs, would be a more robust candidate controller in the presence of unmodeled plant dynamics than a model-based fixed gain linear controller. NASA’s seven-state FRACTAL academic model for ARES I-X was employed as an example launch vehicle on which to develop the controller.
To better understand the difficult dynamic issues, we started with a simplified model that incorporated the inherent instability of the plant and the nonminimum phase nature of the dynamics: an inverted pendulum with an attachable slosh tank. We formulated controllers for this simplified plant with slosh dynamics using control algorithms developed only on a reduced–order model consisting of the rigid body dynamics without slosh. The controllers must be designed to reject three different persistent input disturbances: persistent pulse, step, and sine. We assumed that only position feedback was available, and that rates would have to be estimated.
For comparison, a fixed gain linear controller was developed using the well-known Linear Quadratic Gaussian methodology employing state estimation to obtain rate estimates. For a stable adaptive controller, we used direct adaptive control theory developed by Balas, et al. For this theory we need CB > 0 and a minimum-phase open-loop transfer function. We employed a new transmission zero selection method to develop a blended output shaping matrix which would satisfy these conditions robustly. We used approximate differentiation filters to obtain rates for the adaptive controller. Again for comparison, we redesigned the LQG controller to use the same blended output matrix and filters.
Following the work on the pendulum, the same method was applied to develop an adaptive controller for the FRACTAL launch vehicle model. An adaptive controller stabilizes a rigid body version of FRACTAL over a very long timeline while exceeding all reasonable state and output limits.