Publications (19)
New mathematical models for particle flow dynamics
Denis Blackmore, Roman Samulyak, Anthony Rosato
A new class of integro-partial differential equation models is derived for the prediction of granular flow dynamics. These models are obtained using a novel limiting averaging meth…
Near-field simulations of pellet ablation for disruptions mitigation in tokamaks
Nicolas Bosviel, Paul B. Parks, Roman Samulyak
Detailed numerical studies of the ablation of a single neon pellet in the plasma disruption mitigation parameter space have been performed. Simulations were carried out using FronT…
Evolution of the self-injection process in the transition of an LWFA from self-modulation to blowout regime
Prabhat Kumar, Kwangmin Yu, Rafal Zgadzaj +5
Long wavelength infrared (LWIR) laser driven plasma wakefield accelerators are investigated here in the self-modulated laser wakefield acceleration (SM-LWFA) and blowout regimes us…
SPACE: 3D Parallel Solvers for Vlasov-Maxwell and Vlasov-Poisson Equations for Relativistic Plasmas with Atomic Transformations
Kwangmin Yu, Prabhat Kumar, Shaohua Yuan +2
A parallel, relativistic, three-dimensional particle-in-cell code SPACE has been developed for the simulation of electromagnetic fields, relativistic particle beams, and plasmas. I…
Massively-Parallel Lagrangian Particle Code and Applications
Shaohua Yuan, Mario Zepeda Aguilar, Nizar Naitlho +1
Massively-parallel, distributed-memory algorithms for the Lagrangian particle hydrodynamic method [R. Samulyak, X. Wang, H.-C. Chen, Lagrangian particle method for compressible flu…
Transonic ablation flow regimes of high-Z pellets
Hyoungkeun Kim, Roman Samulyak, Paul Parks
In this letter, we report results of numerical studies of the ablation of argon and neon pellets in tokamaks and compare them with theoretical predictions and studies of deuterium…
Lagrangian particle simulation of hydrogen pellets and SPI into runaway electron beam in ITER
Shaohua Yuan, Nizar Naitlho, Roman Samulyak +5
Numerical studies of the ablation of pellets and shattered pellet injection (SPI) fragments into a runaway electron beam in ITER have been performed using a time-dependent pellet a…
The integrability of Lie-invariant geometric objects generated by ideals in the Grassmann algebra
Denis Blackmore, Yarema A. Prykarpatsky, Roman Samulyak
We investigate closed ideals in the Grassmann algebra serving as bases of Lie-invariant geometric objects studied before by E. Cartan. Especially, the E. Cartan theory is enlarged…
Lagrangian Particle Method for Compressible Fluid Dynamics
Hsin-Chiang Chen, Roman Samulyak, Wei Li
A new Lagrangian particle method for solving Euler equations for compressible inviscid fluid or gas flows is proposed. Similar to smoothed particle hydrodynamics (SPH), the method…
A Comparison Study of Two Methods for Elliptic Boundary Value Problems
Jian Du, Shuqiang Wang, James Glimm +1
In this paper, we perform a comparison study of two methods (the embedded boundary method and several versions of the mixed finite element method) to solve an elliptic boundary val…
Efficient numerical algorithm for multi-level ionization of high-atomic-number gases
Aiqi Cheng, Roman Samulyak
An efficient numerical algorithm for the laser driven multi-level ionization of high-atomic-number gases is proposed and implemented in an electromagnetic particle-in-cell code SPA…
Simulation Study of the Influence of Experimental Variations on the Structure and Quality of Plasma Liners
Wen Shih, Roman Samulyak, Scott C. Hsu +3
Simulation studies of a section of a spherically imploding plasma liner, formed by the merger of six hypersonic plasma jets, have been performed at conditions relevant to the Plasm…
Simulation of plasma loading of high-pressure RF cavities
Kwangmin Yu, Roman Samulyak, Katsuya Yonehar +1
Muon beam-induced plasma loading of radio-frequency (RF) cavities filled with high pressure hydrogen gas with 1% dry air dopant has been studied via numerical simulations. The elec…
AP-Cloud: Adaptive Particle-in-Cloud Method for Optimal Solutions to Vlasov-Poisson Equation
Xingyu Wang, Roman Samulyak, Xiangmin Jiao +1
We propose a new adaptive Particle-in-Cloud (AP-Cloud) method for obtaining optimal numerical solutions to the Vlasov-Poisson equation. Unlike the traditional particle-in-cell (PIC…
An Embedded Boundary Method for Two Phase Incompressible Flow
Shuqiang Wang, James Glimm, Roman Samulyak +2
We develop an embedded boundary method (EBM) to solve the two-phase incompressible flow with piecewise constant density. The front tracking method is used to track the interface. T…
Simulation of beam-induced plasma in gas-filled rf cavities
Kwangmin Yu, Roman Samulyak, Katsuya Yonehara +1
Processes occurring in a radio-frequency (rf) cavity, filled with high pressure gas and interacting with proton beams, have been studied via advanced numerical simulations. Simulat…
Computational Model for Granular Flows based on the Lagrangian Particle Method
Mario Zepeda, Roman Samulyak
A numerical model and parallel software for 3D simulations of granular flows have been developed based on the Lagrangian particle (LP) method [R.Samulyak, X. Wang, H.-C. Chen, Lagr…
On Stability of Targets for Plasma Jet Induced Magnetoinertial Fusion
Roman Samulyak, Lina Zhang, Hyoungekun Kim
The compression and stability of plasma targets for the plasma jet-induced magneto-inertial fusion (PJMIF) have been investigated via large scale simulations using the FronTier cod…
Collider-quality electron bunches from an all-optical plasma photoinjector
Arohi Jain, Jiayang Yan, Jacob R. Pierce +11
We present a novel approach for generating collider-quality electron bunches using a plasma photoinjector. The approach leverages recently developed techniques for the spatiotempor…