Article
Thermodynamics
Biao Xie, Meng Ni, Guobin Zhang, Xia Sheng, Houwen Tang, Yifan Xu, Guizhen Zhai, Kui Jiao
Summary: This study implements comprehensive validation for modeling and simulation of proton exchange membrane (PEM) fuel cell, including overall performance and local characteristics. A simplified model is adopted to improve calculation efficiency, and the validation methodology is clarified by listing undetermined model parameters and analyzing their correlations with voltage losses. The experimental and simulation results are in good agreement, and the importance of liquid water on cell performance is highlighted.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Multidisciplinary Sciences
Zhen Zhang, Jun Ding, Evan Ma
Summary: Plastic flow in metallic glasses is not caused by identifiable local defect regions. Through a realistic model, we found that shear transformations involve only a small percentage of atoms and their locations and distribution vary under different mechanical loading conditions.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Physical
Guobin Zhang, Zhiming Bao, Biao Xie, Yun Wang, Kui Jiao
Summary: The study investigates the influence of a metal foam flow field on transport phenomena and electrochemical reactions in PEM fuel cells using a 3D multi-phase non-isothermal model. Results show that the metal foam design greatly increases fuel cell performance and leads to more uniform distributions of oxygen and current density compared to conventional flow fields.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Linfa Peng, Yue Wan, Diankai Qiu, Peiyun Yi, Xinmin Lai
Summary: This study aims to develop a tolerance design method for dimensional and assembly errors on metallic bipolar plates using a contact behavior model. Results show that dimensional and assembly errors lead to uneven pressure distribution, higher contact resistance, and increased GDL porosity. Recommended acceptable maximum dimensional errors and assembly errors for fuel cells with channel widths of 1.0, 2.0, and 4.0 mm are specified.
JOURNAL OF POWER SOURCES
(2021)
Article
Quantum Science & Technology
Mingxia Huo, Ying Li
Summary: This work proposes an algorithm that combines quantum Monte Carlo with quantum computing to simulate the imaginary-time evolution and solve the ground-state problem. By sampling the real-time evolution operator with a random evolution time according to a modified Cauchy-Lorentz distribution, the expected value of an observable in imaginary-time evolution can be computed. The results show that Monte Carlo quantum simulation is promising even without a fully fault-tolerant quantum computer.
Article
Chemistry, Physical
Mert Tas, Gulsah Elden
Summary: The effects of cell temperature and relative humidity on charge transport parameters are analyzed numerically in this study. The results show that the current densities increase with increasing temperature and humidity, reaching a maximum in the rib regions. The behaviors of electrolyte potentials are similar to the changes in temperature and humidity. The cathode electrical potentials do not change significantly with increasing temperature and humidity.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Physics, Multidisciplinary
Minghui Hu, Youjin Deng, Jian-Ping Lv
Summary: The concept of logarithmic universality presents a new model for describing critical phenomena, characterized by distinct features from the standard scenario. Monte Carlo simulations on the three-dimensional XY model provide strong evidence for the emergence of logarithmic universality. Discussions on finite-size scaling and critical exponent offer a new perspective on understanding critical universality.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Sonke Goessling, Niklas Nickig, Matthias Bahr
Summary: The study focuses on the simulation-based investigation of a PEM fuel cell system with special emphasis on water management, using a detailed 2-D + 1-D stack model to ensure acceptable simulation times.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Physics, Fluids & Plasmas
Deborah Schwarcz, Stanislav Burov
Summary: Recent experiments have shown that using a liquid substrate can improve the production of amorphous materials. Our study demonstrates that introducing motion to the substrate atoms can enhance the self-assembly process of particles on top of the substrate.
Article
Biochemistry & Molecular Biology
Andrzej Patrykiejew
Summary: The phase behavior of two-dimensional systems of Janus-like particles on a triangular lattice was studied using Monte Carlo methods. It was found that the phase behavior strongly depended on the interaction energies between the AB and BB halves, and the topology of phase diagrams was determined by the temperature at which the systems undergo the orientational order-disorder transition.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Engineering, Multidisciplinary
Alsayed Alsobky, Ahmed Hassan
Summary: This study proposes a new methodology to identify the subspace containing all solutions of turning movements using all available data, as well as a framework to evaluate the proposed solution and locate further measurements to achieve the target accuracy. The proposed framework has been validated with positive results at intersections in Edmonton city, Canada.
AIN SHAMS ENGINEERING JOURNAL
(2021)
Article
Mechanics
Haibing Peng
Summary: Despite the widespread use of Navier-Stokes equations in computational-fluid-dynamics (CFD), there are still unanswered questions due to the absence of considering the statistical nature of discrete air molecules. In this study, we propose a statistical mechanics-based approach called the volume-element method, which allows for the numerical evaluation of aerodynamic lift and drag. We obtained pressure and friction values as a function of the angle of attack for flat-plate airfoils, and this method can be directly applied to convex-shape airfoils and combined with Monte Carlo simulations for concave-shape airfoils. This approach not only has implications for aerodynamic applications, but also opens up possibilities for further applications in Boson or Fermi gases.
Article
Chemistry, Physical
Susanta K. Das, Hilniqua A. Gibson
Summary: The study investigated the impact of multi-species transports on the performance of a HTPEMFC by incorporating multi-physics electro-kinetics in a 3D model at 180 C. The results showed overall performance improvements in HTPEMFC at various parametric conditions. The 3D model simulation results will be advantageous for further diagnostic analysis of the HTPEMFC systems.
JOURNAL OF POWER SOURCES
(2021)
Article
Green & Sustainable Science & Technology
Peng Ren, Pucheng Pei, Dongfang Chen, Lu Zhang, Yuehua Li, Xin Song, Mingkai Wang, He Wang
Summary: Metallic bipolar plates (BPs) in fuel cells experience corrosion and surface destruction under automotive operating conditions, with dynamic load and startup-shutdown being the main accelerators. Dynamic potential accelerates the breakdown of passivation layer, while pits rich in Cr-species provide protection. Startup-shutdown drives complex corrosion and passivation stages, leading to global destruction represented by microstructure and pits, while producing a surface film through secondary passivation.
Article
Chemistry, Physical
O. Schullian, H. S. Antila, B. R. Heazlewood
Summary: This study extends the one-dimensional SCMFD approach to three dimensions and introduces a variable time step, allowing for simulation of a wider range of collision environments. The performance of the method is demonstrated through simulations of various test systems, showing excellent agreement with theoretical predictions and analytical models.
JOURNAL OF CHEMICAL PHYSICS
(2022)
