Global Memory Access Modelling for Efficient Implementation of the LBM on GPUs

International audienceIn this work, we investigate the global memory access mechanism on recent GPUs. For the purpose of this study, we created specific benchmark programs, which allowed us to explore the scheduling of global memory transactions. Thus, we formulate a model capable of estimating the execution time for a large class of applications. Our main goal is to facilitate optimisation of regular data-parallel applications on GPUs. As an example, we finally describe our CUDA implementations of LBM flow solvers on which our model was able to estimate performance with less than 5% relative error

Ceiling turbulent asymmetrical air jets under interaction effects of room architectural elements - a full scale experimental characterization

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La simulation des flux radiatifs en milieu urbain : comparaison de stratégies

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Hybrid thermal link-wise artificial compressibility method

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Evaluation of directional quadrature schemes for simulating urban radiative transfer using the Discrete Ordinate Method

International audienceIn the last decades, different numerical methods have been applied to simulate radiative transfer in urban configurations. In cases where atmospheric air is treated as an absorbing gas, it has been shown in many cases that the use of the Discrete Ordinate Method has been shown in many situations to provide a good compromise between calculation cost and accuracy. In this paper, several quadrature schemes for directional integration in the DOM are compared for different urban conditions and types (visible, thermal infrared) of radiation. This allows for determining which angular quadrature scheme is the most appropriate for urban radiative transfer calculations. In conclusion, the Fibonacci quadrature set outperforms all other quadratures in the traditional canyon simulation with a transparent model. Meanwhile, the performance of Level Symmetric Odd and Hybrid quadrature (LSO/LSH) and Equal Weight Odd (EWO) catch up with Fibonacci's in a participative atmosphere model

Studying the evolution of both thermal and kinetic boundary layers in the vicinity of a vertical conductive gypsum plate under dynamic time-depending conditions at the building scale

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Performance Evaluation of an OpenCL Implementation of the Lattice Boltzmann Method on the Intel Xeon Phi

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Hybrid lattice Boltzmann finite difference simulation of mixed convection flows in a lid-driven square cavity

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Numerical simulation of melting with natural convection based on lattice boltzmann method and performed with cuda enabled gpu

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Improving the performance of solar panels by the use of phase-change materials

Abstract: High operating temperatures induce a loss of efficiency in solar photovoltaic and thermal panels. This paper investigates the use of phase-change materials (PCM) to maintain the temperature of the panels close to the ambient. The main focus of the study is the CFD modeling of heat and mass transfers in a system composed of an impure phase change material situated in the back of a solar panel (SP). A variation of the enthalpy method allows simulating the material thermo-physical change of properties. The buoyancy term in Navier-Stokes' momentum conservation equation is modified through an additional term which forces the velocity field to be non-existent when the PCM is solid. For validation purposes, isotherms and velocity fields are calculated and compared to those from an experimental set-up. Results show that adding a PCM on the back of a solar panel can maintain the panel's operating temperature under 40°C for around two hours under a constant solar radiation of 1000W/m²