Investigation of the Impact of Sintering on SOFC Charge Transfer

2011 ◽  
Author(s):  
George J. Nelson ◽  
Brice N. Cassenti ◽  
Aldo A. Peracchio ◽  
Wilson K. S. Chiu
Keyword(s):  
Charge Transfer ◽  
Cross Section ◽  
Performance Metrics ◽  
Periodic Structures ◽  
Variable Cross Section ◽  
Variable Cross ◽  
Two Dimensional ◽  
One Dimensional ◽  
Simplified Approach ◽  
The Impact

Solid oxide fuel cell electrodes are porous composites commonly produced by the sintering of powder compacts. Particle contact geometry within the electrode microstructure has been noted to impact electrode performance, particularly with respect to charge transfer. An analytical modeling concept has been applied to charge transport within the SOFC electrode microstructure using an approach similar to thermal fin analysis. This approach has the ability to account for variable cross-section solid geometry and replicates experimentally observed behavior related to SOFC electrode sintering quality. Microstructural geometries simulated by periodic structures composed of iterated base units with variable cross-section are investigated using two approaches: an axisymmetric one-dimensional analytical solution and an axisymmetric two-dimensional finite element solution. Results are cast in terms of dimensionless parameters and performance metrics that have been developed to assess the quality of SOFC electrode microstructures. Comparison of the one-dimensional and two-dimensional results demonstrates the predictive capabilities of the simplified approach.

scholarly journals Eco-friendly technology of manufacturing complex products made of composites

2019 ◽  
Vol 140 ◽  
pp. 02004
Author(s):  
Aleksey Ignatov ◽  
Rustam Subkhankulov
Keyword(s):  
Composite Materials ◽  
Cross Section ◽  
Manufacturing Process ◽  
Volume Fraction ◽  
Turbine Blades ◽  
Variable Cross Section ◽  
Variable Cross ◽  
Technological Parameters ◽  
Technological Support ◽  
The Impact

Numerous studies in application of modern composite materials show that their advantages can be successfully implemented in manufacturing «smart» products. This study proposes an improved technological method of manufacturing multilayer environmentally friendly products with a variable cross section, which allows us to expand the possibilities of using modern polymer composite materials (PCM). The technology allows manufacturing products of the most complex geometric shapes, such as wind turbine blades. The aim of the study is the technological support of engineering production in the manufacture of multilayer products of variable cross section made from PCM. Scientific novelty consists in identifying the patterns of implementation and management of the manufacturing process of multilayer products of variable cross-section, and establishing the influence of structural and technological parameters of the manufacturing process on their operational characteristics. The relationship between the pressure of a hot directed air stream and the volume fraction of pores in the hardened material of a multilayer composite product with a variable cross section during layer-by-layer application is investigated. During the study, fundamental and applied principles of mechanical engineering technology, material resistance, adhesion theory, mathematical statistics tools and software were used to process the results of the experiment. Based on the results of laboratory studies, a methodology has been developed for effective prediction of pore content in the manufacturing of composite products. The introduction of the presented technology and the corresponding original methodology into production will reduce the complexity and energy costs of manufacturing composite products, improve their quality and reduce the impact of toxic components from composite materials on workers.

Stress Wave Propagation Analysis in One-Dimensional Micropolar Rods with Variable Cross-Section Using Micropolar Wave Finite Element Method

2018 ◽  
Vol 10 (04) ◽  
pp. 1850039 ◽  
Author(s):  
Mohsen Mirzajani ◽  
Naser Khaji ◽  
Muneo Hori
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Wave Propagation ◽  
Cross Section ◽  
Variable Cross Section ◽  
Stress Wave Propagation ◽  
Rotational Degree ◽  
Variable Cross ◽  
One Dimensional ◽  
Element Method

The wave finite element method (WFEM) is developed to simulate the wave propagation in one-dimensional problem of nonhomogeneous linear micropolar rod of variable cross-section. For this purpose, two kinds of waves with fast and slow velocities are detected. For micropolar medium, an additional rotational degree of freedom (DOF) is considered besides the classical elasticity’s DOF. The proposed method is implemented to solve the wave propagation, reflection and transmission of two distinct waves and impact problems in micropolar rods with different layers. Along with new solutions, results of the micropolar wave finite element method (MWFEM) are compared with some numerical and/or analytical solutions available in the literature, which indicate excellent agreements between the results.

scholarly journals The lateral vibrations of bars of variable section

1917 ◽  
Vol 93 (654) ◽  
pp. 506-519 ◽  
Keyword(s):  
Cross Section ◽  
Formal Analysis ◽  
Detailed Examination ◽  
Variable Cross Section ◽  
Variable Cross ◽  
Biological Application ◽  
Lateral Vibrations ◽  
Variable Section ◽  
Set Up ◽  
The Impact

The present investigation, though strictly mathematical in character, arose in connection with a suggestion, put forward by Prof. A. Dendy and the present author in another paper communicated to the Society, that the siliceous deposits found on certain sponge spicules occurred at nodes of the spicules, regarded as vibrating rods. These vibrations, being set up and maintained by the impact of currents of water on the spicules, are necessarily of the lateral type. For the detailed examination of such a suggestion, it is necessary to obtain a comprehensive account of the positions of the funda­mental nodes on a free-free bar, as dependent on the law of variation of its cross-section. The present paper contains, in fact, the formal analysis whose results were quoted without proof in the other paper. This analysis is of considerable generality, as will appear, and the particular examples selected for purposes of illustration, together with the manner in which the variable cross-section is dealt with, have been determined by the requirements of the biological application already mentioned. One general problem is in view throughout the work, and it may be stated as follows

scholarly journals The Impact of Damage in Inconel 718 on Hardness Measured by the Vickers Method

2015 ◽  
Vol 2015 (7) ◽  
pp. 69-79
Author(s):  
Maciej Malicki ◽  
Bartosz Madejski
Keyword(s):  
Cross Section ◽  
Inconel 718 ◽  
Variable Cross Section ◽  
Damage Parameter ◽  
Variable Cross ◽  
Cross Section Area ◽  
Hardness Tests ◽  
Section Area ◽  
Individual Specimen ◽  
The Impact

Abstract To prevent failure of machine components it is necessary to measure material damage generated in a component throughout its entire lifetime. Damage can be quantified by means of damage parameters. This paper considers the usefulness of hardness measurements to evaluate damage parameter in Inconel 718. Vickers hardness tests were performed on a specimen with a variable cross section area after tensile testing. The specimen’s geometry enabled the evaluation of damage parameter in respect of hardness measurements made on one individual specimen.

Analysis of the distribution of BAD generated during the normal penetration of a variable cross-section EFP on RHA

2019 ◽  
Author(s):  
Boyang XING ◽  
Yunhui HOU ◽  
Zhenyan GUO ◽  
Dongjiang ZHANG ◽  
Liang CHEN ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Impact Velocity ◽  
Cross Section ◽  
Variable Cross Section ◽  
Variable Cross ◽  
Thin Target ◽  
The Impact

Abstract The purpose of this study is to analyse how the thickness of Rolled Homogeneous Armor (RHA) and impact velocity of an Explosively Formed Projectile (EFP) influence the middle mass behind-armor debris (BAD) when a variable cross-section EFP penetrates RHA normally. Numerical simulation is adopted, the thickness of RHA varies from 10mm to 70mm, and the impact velocity of the EFP varies from 1650m/s to 1860m/s. The results indicate that: (1) when the impact velocity of the EFP is 1650m/s and the thickness of RHA varies from 10mm to 70mm, p1g of the RHA and EFP decreases with increasing H0. The thin target could be used to produce a large proportion of the middle mass BAD from RHA (including BAD from the EFP and BAD from the RHA and EFP). (2) When the impact velocity of the EFP varies from 1650m/s to 1860m/s and the thickness of the RHA is 40mm, p1g of the RHA is less than 50%, p1g of the EFP is more than 70%, and p1g of the RHA and EFP is more than 50%.

scholarly journals Numerical Study of Detonation Wave Propagation in the Variable Cross-Section Channel Using Unstructured Computational Grids

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Alexander Lopato ◽  
Pavel Utkin
Keyword(s):  
Detonation Wave ◽  
Cross Section ◽  
Large Scale ◽  
Numerical Study ◽  
Variable Cross Section ◽  
Approximation Order ◽  
Computational Grids ◽  
Detonation Waves ◽  
Variable Cross ◽  
Two Dimensional

The work is dedicated to the numerical study of detonation wave initiation and propagation in the variable cross-section axisymmetric channel filled with the model hydrogen-air mixture. The channel models the large-scale device for the utilization of worn-out tires. Mathematical model is based on two-dimensional axisymmetric Euler equations supplemented by global chemical kinetics model. The finite volume computational algorithm of the second approximation order for the calculation of two-dimensional flows with detonation waves on fully unstructured grids with triangular cells is developed. Three geometrical configurations of the channel are investigated, each with its own degree of the divergence of the conical part of the channel from the point of view of the pressure from the detonation wave on the end wall of the channel. The problem in consideration relates to the problem of waste recycling in the devices based on the detonation combustion of the fuel.

scholarly journals The Vibration of Tubular Beam Conveying Fluid with Variable Cross Section

2020 ◽  
Vol 65 (1) ◽  
pp. 56-62
Author(s):  
Mohamed Gaith
Keyword(s):  
Flow Velocity ◽  
Cross Section ◽  
Natural Frequencies ◽  
Variable Cross Section ◽  
System Stability ◽  
Variable Cross ◽  
Cross Sectional ◽  
Critical Flow Velocity ◽  
Constant Flow Rate ◽  
The Impact

The dynamics and stability of flow induced vibration of flow conveying in pipes particularly in case of high velocity flow may lead to severe damage. Predicting the circular natural frequencies and critical fluid velocities is an important tool in design and prevent system failures. In this study transverse dynamic response of simply supported pipe with variable tubular cross sectional area carrying fluid with a constant flow rate is investigated. Euler Bernoulli's beam theory is used to model the pipe. Hamilton's principle will be used to produce the governing equation of motion for the system. The resulting partial differential equation is solved using Galerkin's technique. The impact of the flow velocity and non-uniform variable cross section on the natural frequencies of the system, critical flow velocity and system stability is presented.

Sign in / Sign up

Export Citation Format

Share Document