The design process of a superconducting current limiter (SFCL) requires simulation and definition of its electrical, magnetic and thermal properties in form of equivalent circuits and mathematical models. However, any change in SFCL parameters: dimension, resistance, and operating temperature can affect the limiting mode, quench time, and restore time. In this paper, following the simulation of...

In this paper we numerically solve the stationary inviscid flow around an airfoil. Using the second-order explicit Runge–Kutta method in combination with the MUSCL scheme and the minmod limiter, we do not obtain a machine accurate solution. This has already been observed in literature and is explained by the non-differentiability of the minmod limiter. An analysis of the limiter shows that it i...

Alcator C operations commenced with discharge cleaning and tokamak operation using hydrogen filling gas. Prior to and during these experiments no deuterium gas was allowed into the device. The earliest operation resulted in dosimeter readings of a few Roentgen per shot in the vicinity of the limiter and a localized source of neutron emission of 9 up to 10 neutrons/shot. A strong correlation of ...

A combined IR and visible camera system [G. A. Wurden et al., "A high resolution IR/visible imaging system for the W7-X limiter," Rev. Sci. Instrum. (these proceedings)] and a filterscope system [R. J. Colchin et al., Rev. Sci. Instrum. 74, 2068 (2003)] were implemented together to obtain spectroscopic data of limiter and first wall recycling and impurity sources during Wendelstein 7-X startup ...

Experiments are underway on the Alcator C Tokamak with over 1 MW of RF power injected into the plasma at a frequency of 4.6 GHz to study both heating and current drive effects. During these studies, impurity generation from limiter structures has been observed. The RF induced impurity influx is a strongly nonlinear function of net injected power. For Prf < 500 kW, only small effects are seen. A...

The difference in the H-mode power threshold in divertor and limiter configurations is numerically investigated by analysing the effect of boundary conditions imposed on the last closed magnetic surface (LCMS) and given by prescribed density and temperature e-folding lengths, δn and δT , respectively. It is demonstrated that the variation of δn and δT significantly affects the H-mode power thre...

This paper studies the effect of new suggested ferroresonance limiter on controlling ferroresonance oscillations in the power transformer. It is expected that this limiter generally can control the ferroresonance. For studying these phenomena, at first ferroresonance is introduced and a general modeling approach is given. A simple case of ferroresonance in a three phase transformer is used to i...

One of the main challenges in computational simulations of gas detonation propagation is that negative density or negative pressure may emerge during the time evolution, which will cause blow-ups. Therefore, schemes with provable positivity-preserving of certain quantities such as density and pressure are desired. First order and second order positivity-preserving schemes were well studied, e.g...