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Lower hybrid simulation code (LSC) is integrated into transport code ONETWO to model discharges of EAST with heating and current drive using both lower hybrid wave and neutral beam injection. To test the integration, the current profiles driven by both lower hybrid wave and neutral beam injection are presented for a given equilibrium and sample density and temperature profiles before carrying out a time advancing simulation. For a steady state H-mode discharge, the temperature profiles are evolved using GLF23 transport model with a boundary value specified at the normalized minor radius ?N = 0.9. A case of steady state with non-inductively driven current accounting for up to 80% is presented.

Reconstruction of experimental axisymmetric equilibria is an important part of tokamak data analysis. Fourier expansion is applied to reconstruct the vessel current distribution in EFIT code. Benchmarking and testing calculations are performed to evaluate and validate this algorithm. Two cases for circular and non-circular plasma discharges are presented. Fourier expansion used to fit the eddy current is a robust method and the real time EFIT can be introduced to the plasma control system in the coming campaign.

Two phases of a DIII-D discharge with and without magnetohydrodynamics (MHD) activity are analysed using ONETWO code. The toroidal momentum flux is extracted from experimental data and compared with the predictions by neoclassical theory, Gyro?Landau fluid transport model (GLF23) and Multi-Mode model (MMM95). It is found that without MHD activities GLF23 and MMM95 provide a reasonable description while with MHD activity no model alone can fully describe the experimental momentum flux. For the phase with MHD activity a simple model of resonant magnetic drag is tested and it cannot fully explain the plasma slowing down observed in experiment.

The effect of the toroidal flow on the equilibrium of tokamak plasmas is a sensitive point for high performance plasma and its precise control. In this paper the effect is studied numerically using the EFIT (Equilibrium Fitting) code on EAST (Experimental Advanced Superconducting Tokamak). Firstly, the numerical calculation exhibits a clear outward shift of pressure contour from the magnetic surfaces in the plasma core and the shift grows with the increase of the toroidal velocity. The peak shift of 8% is observed when the ratio between the plasma velocity and the Alfv?n speed equals to 0.15. Secondly, it is shown that the magnetic surfaces shift outwards from those without flow. With a certain plasma current the safety factor on the magnetic axis decreases as the plasma flow velocity increases. The magnetic shear increases about 10% on the plasma boundary compared with the case without flow.

The use of cast aluminum components in automotive applications is increasing rapidly. Cast Al components are allowing the industry to meet the current as well as future customer and legislative requirements regarding vehicle size and performance. The 319 Al alloy, which contains 3-4wt%Cu and 6-7wt%Si, is utilized in Ford automobile engine block castings. After heat treatment, this alloy exhibits higher yield and tensile strength levels than other grades of cast Al alloys. However, some other mechanical properties of the 319 Al alloy need to be improved, and thus a lot of these alloys are not applicable for engine blocks. The bulkhead section of the engine block is susceptible to high cycle fatigue (HCF) during operation. Recent IRC work showed that it might be possible to improve microstructures and mechanical properties of 300-series of cast Al alloys through the optimization of Si, Cu and Sr levels in the castings. This project concerns the optimization of Si, Cu and Sr contents for the improvement of microstructures and properties of 300-series casting Al alloys, particularly HCF properties. In order to investigate the effects of chemical composition and cooling rate (CR) on microstructures and properties, six plates with various chemical compositions were cast at Ford CPDC. The plates were chilled at one end so that temperature gradients and different CR were created. This research project has investigated the effects of chemical compositions (Si, Cu and Sr), temperature gradient and CR on the microstructures, properties and casting defects of the Al alloys typically utilized for automotive engine blocks. A criterion has been developed for the improvement of next-generation engine component durability through the optimization of chemical compositions, and solidification conditions. The influences of heat treatment parameters on Cu phase(s) area fractions and hardness have also been investigated. The experimental work performed showed that the secondary Dendrite Arm Spacing (SDAS), Silicon Modification Level (SML), Porosity Area Fraction (PAF), Cu phase(s) area fraction (CuAF) and hardness were affected by the CR. Slight changes on the above parameters were caused by microalloying changes.