We present an error analysis and further numerical investigations of the Parameterized-Background Data-Weak (PBDW) formulation to variational Data Assimilation (state estimation), proposed in [Y Maday, AT Patera, JD P...
详细信息
Fire-fight helicopter is the core of forest aviation *** virtual reality technology to train the crew of helicopter can improve their skill to put out fire efficiently and reduce property ***,current methods of visual...
详细信息
Fire-fight helicopter is the core of forest aviation *** virtual reality technology to train the crew of helicopter can improve their skill to put out fire efficiently and reduce property ***,current methods of visualizing water-dropping of helicopter in virtual environment cannot simultaneously ensure real-time performance and *** the one hand,the existing visualization methods,which have been widely used,are often just visual imitations and cannot reflect the physical laws of *** the other hand,complex computations are required for the general fluid modeling method,which cannot meet the requirement of real-time response in a VR *** is of great significance to establish a simulation-oriented model of water-dropping from helicopter for achieving realistic water visualization and further increasing the fidelity and immersion of the virtual *** this paper,we demonstrate an effective approach to establish a water-dropping model of helicopter and visualize it in a VR system,simulating physical laws and virtual effects at the same time.
A meso-macro scale model for dynamic fracture of functional graded material is proposed in present work. The dynamic piecewise-exponential (DPE) model is extended to the meso-macro scale by the data mining method. Wit...
详细信息
A mesoscale numerical model for the damage and fracture behavior of particle reinforced composites is proposed in present work. In this model, the digital image technique is used to reconstruct the real microstructure...
详细信息
This paper presents an investigation about the plasticity correction factor, Ke, proposed in the RCC-M code, for the correction of elastic stress range exceeds twice the yield stress which results from both mechanical...
详细信息
Two-color laser induced fluorescence (LIF) technique is applied to investigate the temperature distribution in rod bundles with spacer grid in this paper. In order to evaluate the characteristic, dye spectrum was anal...
详细信息
In the nuclear power station, the steam-water separator is a crucial appliance, a sequence of droplet lifecycle phenomena take place, including the droplet formation, droplet motion in the steam space, the mutual coll...
详细信息
In the nuclear power station, the steam-water separator is a crucial appliance, a sequence of droplet lifecycle phenomena take place, including the droplet formation, droplet motion in the steam space, the mutual collisions between droplets, droplet extinction and the phase transformation. Together with the entraining steam, the droplets experiencing above complex processes consist a typical sparse two-phase flow, which can be well investigated by the Euler-Lagrange approach in terms of numerical simulations. With the Euler-Lagrange method, the microscopic behavior of the droplets and the steam-water separating mechanism are promising to be captured. When applying the Euler-Lagrange approach to simulate the droplets motion in the fluid field, one should first obtain the fluid parameters surrounding the droplets by the interpolation method, which may significantly influence the efficiency and precision of subsequent simulation results. In the present work, we examined the performance of four different interpolation schemes in the simulation of the droplet-steam flow inside the steam-water separator, including the k-d tree and the brute force search algorithm, the nearest point and 4-point interpolation method, and the boundary layer meshes refinement and total mesh refinement method. The computational efficiency and precision of the four methods were studied in comparison. The nearest point interpolation scheme takes less computing time, whereas with lower accuracy. Therefore, the sufficiently fine meshes are necessary to improve the calculation accuracy, which in turn lead to the reduced computational efficiency. The accuracy of the four-points interpolation scheme is remarkably higher than that of the nearest point interpolation scheme at the cost of much more (more than 2 folds) CPU time. To make a trade-off between the efficiency and precision, a high efficiency and precision interpolation method is put forward by combining the nearest point interpolation scheme
To study the development mechanisms and flow structure characteristics of the free surface vortices and get a better understanding of the vortices phenomena. Two-phase, three dimensions, transient CFD simulations of f...
详细信息
The transient performance of the Secondary Passive Residual Heat Removal system (SPRHR) for a small modular PWR was studied, the study focused on the thermal hydraulic characteristics at different initial water invent...
详细信息
暂无评论