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The generation of realistic incoming turbulence is often a prerequisite to carrying out accurate scale-resolving simulations of spatially developing unsteady flows around complex geometries, like the ones found in many industrial settings. The challenge of developing synthetic turbulence generation methods that are ideally accurate, flexible, robust and cheap to compute is object of active research and this talk describes our steps in that direction. I will describe an extended version of the Synthetic Eddy Method that is being developed in PyFR and the implementation strategy. I will also present simulation results for two test cases: a plane turbulent channel flow and the turbulent flow over a model high rise building.

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In this paper, an iterative interference cancellation multiuser detection (MUD) method is proposed for overloaded multiple-input multiple-output (MIMO) coded orthogonal frequency division multiplexing (OFDM) systems. In the first iteration, the low complexity RAKE reception is employed, and a successive interference cancellation (SIC)-based approach is used to choose the stronger user. In each iteration, the soft output of the convolutional decoder is fed back to improve the performance of the parallel interference cancellation (PIC). The simulation results show that, this technique can achieve near-optimum bit error rate (BER) performance at low SNR, with lower complexity than optimum maximum likelihood (ML) methods. [ABSTRACT FROM PUBLISHER]

The goal of this work is to present and discuss two methods to effectively represent the MTL with a reduced number of conductors in case of groups of wires shorted together and/or grounded. Reducing criteria are applied to the MTL cells that represent the 2×25 kV-50 Hz AC high-speed railway electrification system, also including the high voltage grid that supply the Electrical Substation. The obtained models are used to evaluate the disturbances on the track circuits caused by trains harmonic current injection. The numerical results are reported, compared and discussed. [ABSTRACT FROM PUBLISHER]

The common mode to differential mode transformation of rail currents and voltages normally present in double track railway systems is considered. Differential mode signals are a potential threat for a broad range of signalling circuits based on the track circuit principle. Operators' and manufacturers' attention is normally on exceptional losses of symmetry of the traction return circuit under fault or failure condition, but it is shown that a theoretical 9% transfer of the traction return current can occur on the opposite track under normal conditions. [ABSTRACT FROM PUBLISHER]

Electromechanical analysis and simulation of traction systems are required to estimate the power consumption, to size the power system and to optimize system parameters for energy saving. The number of variables and parameters (mechanical and electrical) is huge, affected by various degrees of uncertainty. An integrated simulation approach is presented, where the requisites for the correct evaluation of regenerative capability are considered. [ABSTRACT FROM PUBLISHER]

A deep research on the contact line (T)-negative feeder(F) short-circuit impedance is made in this paper on the basis of analyzing the advantages and disadvantages of all existing parallel AT power supply system fault location methods . Then, the simulation model of the all parallel AT traction power supply system is established and the characteristic of system impedance under T-F short-circuit condition is simulated and analyzed. The results show that the subsection impedance method basically corresponds to the requirement of engineering application. It also provides some theoretical reference for the T-F short-circuit fault analysis of all parallel AT power supply system. [ABSTRACT FROM PUBLISHER]