A Cloud-Based Real Time Polluted Gas Spread Simulation Approach on Virtual Reality Networking.

It is a difficult problem to realize the online simulation of fluid phenomena in a wide range of networking-based virtual reality scenes. Real-time solution and three-dimensional (3D) rendering of fluid dynamic process pose a great challenge to the online computing capability of networking. Aiming to model the spread characteristics of polluted gas, this paper constructs a polluted gas simulation model using computational fluid dynamics in a cloud computing environment. This model is flexible and accepts environmental parameters, such as the wind field and ground features in a cloud-based virtual world. Constrained boundary models are proposed for simulating the interaction between polluted gases and a virtual reality scene. An iterative semi-Lagrangian method with over-relaxation is adopted for a fast solution to the model with both simplicity and fidelity. The reported experiments show that our solution can realistically simulate the movement patterns and real-time temporal-spatial dynamics of polluted gas in a large-scale 3D online virtual world while responding to environmental changes interactively. Two typical fluid simulation pipelines are proposed to reasonable use of cloud computing resources for solution and rendering. The experiments demonstrated that the solution performance of our method is better than the same other methods, and this simulation approach achieves real-time simulation of polluted gas spread in a large-scale scene with online ordinary PC, laptop, or mobile device. This paper proposes a solution useful for cloud-based virtual reality and augmented reality networking, and some other real-time applications dealing with fluid phenomena. This paper may provide basic method and tool for urban computing and policy-making of the smart city.