Radiation-Ablation Coupling for Capsule Reentry Heating via Simulation and Expansion Tube Investigations

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In the polar regions, the extreme cold and dark atmosphere of the winter season imposes stringent conditions on the planetary boundary-layer (PBL) leading to limited vertical atmospheric mixing and increasing the severity of air pollution episodes. Understanding the physical and chemical transformations affecting air pollution critically depends on our ability to accurately describe the dynamics of the PBL. This requires an adequate combination of modeling, ground-based observations, and vertical profile me

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Machine learning algorithms are widely used to replace or accelerate highfidelity codes and to provide physical insight in complex problems. In this work, a random forest is applied to replace a 3D full-wave simulation performed using the COMSOL Multiphysics software. In our simulation, a microwave beam is propagating through a cylindrically shaped plasma and is scattered by it. The training data of the random forest consist of the electron density profiles and the corresponding distributions of the microwa

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Temperature and salinity, with largely different diffusivities, make a perfect couple that drives thermohaline flow (double diffusive convection where heat and salt are the two main concerned properties) in porous media wherever their gradients co-exist. Studies of double diffusion convection have revealed various flow regimes generated by instable and even stable vertical stratification of heat and salt including diffusive, finger, and mixed flow regimes. In the context of seawater intrusion in shallow coa

An integrated numerical system is established to model time-dependent behavior of the neoclassical tearing mode (NTM) in a tokamak which solves the modified Rutherford equation (MRE) by coupling with plasma transport, equilibrium, heating and current drive ...

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This article presents an experimental study of upward flow boiling heat transfer in multiport tubes. Usually, multiport tubes are utilized horizontally in automotive and air-conditioning systems while here there is interest in vertical flow as part of a two-phase thermosyphon electronics cooling system. Experiments were carried out in a flat aluminum extruded multiport tube, which was composed of 7 parallel rectangular channels (1.1mm × 2.1mm) with a hydraulic diameter of 1.4 mm. Two refrigerants, R245fa an

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Heat loads on the JET MarkIIHD divertor are measured by IR thermography in high triangularity plasmas with edge conditions of advanced tokamak scenarios (AT). AT scenarios operate at low density (n(e,av) < 5 x 10(19) m(-3) at JET) to maximise the non inductive current drive, leading to high target temperature (20 < T-e < 40 eV), hence high heat loads. Comparisons with a typical baseline inductive scenario (n(e,av) similar or equal to 10 x 10(19) m(-3)), show that for similar input power (similar or equal to

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Structural stability issues in planar solid oxide fuel cells (SOFC) arise from the mismatch between the coefficients of thermal expansion (CTE) of the components. The stress state at operating temperature is the superposition of several contributions, which differ depending on the component. First, the cells undergo residual stresses due to the sintering phase during the manufacturing process. Furthermore, the load applied during the assembly of the stack to ensure the electric contact and flatten the cells

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Ferritic/martensitic steels considered as first-wall candidate materials for fusion reactors experience significant radiation hardening at temperatures below similar to400 degreesC. Experimental evidence suggests that the observed defects are large interstitial dislocation loops with Burgers vector b = and b = (1)/(2). In this work, the atomic character of and (1)/(2) loops is investigated with molecular dynamics simulations and the atomic configurations are used to calculate the defec

The primary damage formation in Mo is investigated using molecular dynamics (MD) simulation with embedded-defect (ED) and embedded-atom method (EAM) interatomic potentials. The former is similar in spirit to the latter but includes an approximate treatment of bond directionality in the many-body interaction. MD simulations are used to calculate threshold displacement energy as function of crystallographic orientation and displacement cascade evolution resulting from primary knock-on atoms (PKAs) with energi

Radiation-Ablation Coupling for Capsule Reentry Heating via Simulation and Expansion Tube Investigations

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