VR-CFD : interactive simulation of computational fluid dynamics

Abstract

Computational Fluid Dynamics (CFD) has been an essential application that helps reduce modelling, simulation and testing time and costs in modern world. Its application spans across industries from aeronautics, turbomachinery, biochemistry to civil engineering (Senan & Thabit H, 2018). As a result, it is an important skill to mechanical and aeronautical engineering students aspiring to become an engineer in fluid dynamics in future. To fulfil the industry’s demand for engineering talents with CFD skills and students’ desire to learn more about numerical methods in solving complex fluid flow problems, tertiary academic institutions such as Nanyang Technological University offer an introductory course of CFD to its undergraduates in the School of Mechanical and Aerospace Engineering. However, there are many abstract math and physics concepts in many fluid dynamics and CFD fluid flow problems which are essential for students to understand. The conventional teaching method is heavily reliant on equation derivation and manual calculation (Zhou et al., 2017). Yet, the static illustrations and abstract equations used in-class seem removed from the real world as they cannot lead to an intuitive visualization of the problem. Due to the difficulties in visualization and tedious equation derivation which tends to be less interesting over time, students often feel discouraged in the course of learning, resulting in poor learning efficiency and lack of true understanding. Thus, teaching these classes have always been a challenge (Zhou et al., 2017). Over the past few decades, various forms of graphic representations and animations have been incorporated in teaching the subject (Su, 2013). However, most of them, including commercial CFD software packages such as ANSYS Fluent, only show the resulting 3D solution model on a flat 2D screen. This leads to a lack of real-time interaction II with the model for students to explore and analyse the problem in 3D in detail. This is especially true for transient fluid flow problems where the visualization of flow parameters at different locations changing over time is essential but difficult to implement in a form that allows interaction on current CFD platforms. As a result of this lack of interactivity, students may not be able to truly understand the CFD simulation results and the physics behind it to solve future problems (Zhou et al., 2017). To solve this problem and enhance learning efficiency in CFD for aerodynamic fluid flow problems, the author designed and developed a Virtual Reality (VR) application VR-CFD. VR offers an immersive 3D environment for a more interactive simulation and visualization experience which has been shown to improve learning efficiency (Goldee, 2012). CFD simulation was done on ANSYS Fluent for a fluid flow problem involving a Red Turtle Shell and then transferred to the VR-CFD application for visualization and interaction. The educational VR application was developed on Unity3D game engine and includes integrated modules that address selected concepts in CFD and aerodynamics. The developed VR-CFD application utilized an attractive design with bright colours, familiar game characters and game-like user interface aimed to make the introductory CFD class fun, interactive and engaging, helping students intuitively grasp the physics concepts. It is hoped that with further development on the early prototype demonstrated in this paper, the VR-CFD application could truly contribute to students’ learning in fluid dynamics problems and how CFD is used to solve them, therefore revolutionizing the way traditional mechanical engineering subjects are taught in class.