A5089036199- Fuel Cells and Related Materials
- Supercapacitor Materials and Fabrication
- CO2 Reduction Techniques and Catalysts
- Electrocatalysts for Energy Conversion
- Topology Optimization in Engineering
- Additive Manufacturing and 3D Printing Technologies
- Electrochemical Analysis and Applications
- Anodic Oxide Films and Nanostructures
- Advanced Numerical Methods in Computational Mathematics
- Advanced Battery Technologies Research
- Enhanced Oil Recovery Techniques
- Model Reduction and Neural Networks
- Neuroscience and Neural Engineering
- Matrix Theory and Algorithms
- Hydraulic and Pneumatic Systems
- Molecular Junctions and Nanostructures
- NMR spectroscopy and applications
- Carbon Dioxide Capture Technologies
- Ionic liquids properties and applications
- Nonlinear Dynamics and Pattern Formation
- Manufacturing Process and Optimization
- Membrane-based Ion Separation Techniques
- Nanopore and Nanochannel Transport Studies
- Civil and Geotechnical Engineering Research
- Advanced Mathematical Modeling in Engineering
Lawrence Livermore National Laboratory
2022-2024
University of Oxford
2019-2020
Dr. Reddy's Laboratories (India)
1994
For both isothermal and thermal petroleum reservoir simulation, the constrained pressure residual (CPR) method is industry-standard preconditioner. This a two-stage process involving solution of restricted system. While initially designed for case, CPR also standard cases. However, its treatment energy conservation equation does not incorporate heat diffusion, which often dominant in In this paper, we present an extension CPR: pressure-temperature (CPTR) method, where system solved first...
Using \textit{ab initio} microkinetic simulations coupled with a two-dimensional continuum transport model, this study models electrochemical CO${}_{2}$ reduction in flow reactor spatial resolution of key reaction parameters.
In this paper, we introduce a density-based topology optimization framework to design porous electrodes for maximum energy storage. We simulate the full cell with model that incorporates electronic potential, ionic and electrolyte concentration. The system consists of three materials, namely pure liquid solids anode cathode, which determine optimal placement. use separate potentials each electrode, allow interdigitated designs. As result, penalization is required ensure cathode do not touch,...
Rechargeable batteries that incorporate shaped three-dimensional electrodes have been shown to increased power and energy densities when compared a conventional geometry, i.e. planar cathode anode sandwich an electrolyte. Electrodes can be enable higher active material loading, while keeping ion transport distances small. However, the relationship between electrical mechanical performance of remains poorly understood. Many electrode designs explored, where are individually or intertwined,...
Bicarbonate electrolytes are used in a range of chemical processes; however, resolved simulation these is difficult, as disparate reaction time scales lead to numerical stiffness and the formation fine boundary layers. Based on several physically motivated approximations, we reduce full set reactions within bicarbonate electrolyte simpler subset, eliminating stiffness. We supported this simplification via two-variable singular perturbation expansion demonstrated that under neutral conditions...
The transition from fossil fuels to renewable energy has brought about a rapid increase in the availability of clean electricity.However, electricity generated sources such as wind and solar are limited intermittent operation due daily seasonal variation.One solution is utilize electrochemical devices storage manufacturing applications, where they can harness surplus decarbonize chemical industries traditionally reliant on petrochemical feedstocks.Managing growing prevalence underscores...
Rechargeable batteries that incorporate shaped three-dimensional electrodes have been shown to increased power and energy densities for a given footprint area when compared conventional geometry, i.e., planar cathode anode sandwich an electrolyte. Electrodes can be enable higher loading of active material, while keeping the ion transport distance small, however, relationship between electrical mechanical performance remains poorly understood. A variety electrode shapes explored, where are...
In this presentation, we introduce a gradient-based shape optimization framework to design porous electrodes for maximum energy storage. Lithium-ion batteries are becoming an increasingly important source and storage device. Large surface area that advocates high reaction rates often leads small porosities deteriorate electrochemical transport, which significantly restricts ion penetration depth, limiting the material utilization in planar electrodes. Consequently, architected required...
Electrochemical CO 2 reduction has emerged as an attractive technique to sustainably produce valuable fuels and chemicals, while reducing emissions. In addition the specific electrode material, microenvironment local interface – e.g., electrolyte pH, concentration, buffer concentration plays a significant role in determining selectivity activity of electrolyzer. this work, we demonstrate multi-scale approach, where microkinetic simulations Au are coupled two-dimensional continuum transport...
Electrochemical energy storage (EES) and conversion devices (e.g. batteries, supercapacitors, reactors) are emerging as primary methods for global efforts to shift dependence from limited fossil fuels towards sustainable renewable resources. These devices, while showing great potential meeting some key metrics set by conventional technologies, still face significant limitations. For example, an EES device tends exhibit large density lithium-ion battery) or power supercapacitor), but not...
Supercapacitors exhibit rapid charge/discharge times and have attracted considerable attention within the automotive, aerospace, telecommunication industries. The high electrical conductivity surface area of porous carbons been attractive for supercapacitor electrodes. Fabricating thick electrodes is one strategy to further increase energy density due a higher volume fraction active material. However, suffer from sluggish charged species transport. In this work, we investigate use...
In contrast to conventional planar electrodes, the use of electrodes with a three-dimensional (3D) shape has been shown be an effective way increase both power and energy densities Li-ion battery. These 3D shapes allow batteries overcome some capacity rate performance trade-offs. For instance, they enable higher active-material loading, while keeping transport pathways fixed allowing for better material utilization. There are variety ways can shaped: each electrode individually shaped...
Gas Diffusion Electrodes (GDEs) have arisen as a popular CO2 electrolyser configuration due to the improved mass transfer properties and higher current densities possible in comparison liquid-fed system. In this work, we aim understand transport regimes single liquid-filled pore of GDE, i.e., an idealized model porous catalyst layer. previous Butler-Volmer (BV) expressions been used CO evolution reaction Hydrogen Evolution Reaction (HER). study, extend that few ways: (1) MicroKinetic Model...
Electrochemical carbon dioxide reduction (eCO 2 R) has emerged as a promising approach to produce high-value fuels and chemicals using renewable energy sources. In particular, Cu catalysts can convert CO wide range of hydrocarbon oxygenate products, including CO, formate, ethanol ethylene. However, the activity selectivity eCO R is highly dependent on mass transport corresponding reaction microenvironment present under operating conditions. this talk, we an integrated framework that combines...
The properties of rechargeable lithium-ion batteries are determined by the electrochemical and kinetic their constituent materials as well underlying microstructure. discovery 2D 3D mesoscale architectures tailored to diverse applications remain an open challenge it cannot be approached empirically. In this work, we leverage design flexibility offered several additive manufacturing methods (e.g. direct ink write, projection micro-stereolithography, etc.) engineer architecture device...
Typical porous electrodes are homogeneous, stochastic collections of micron-scale particles offering few opportunities for engineering higher performance. To leverage recent breakthroughs in advanced and additive manufacturing, we use topology optimization to design electrochemical energy storage devices such as batteries supercapacitors. Energy density is maximized, leading non-trivial geometries that outperform monolithic electrodes. These facilitate ionic transport lead better electrode...
Scaling up new scientific technologies from laboratory to industry often involves demonstrating performance on a larger scale. Computer simulations can accelerate design and predictions in the deployment process, though traditional numerical methods are computationally intractable even for intermediate pilot plant scales. Recently, component reduced order modeling method is developed tackle this challenge by combining projection discontinuous Galerkin domain decomposition. However, while...