Fluid-Structure Interaction

By Jim Romeo

Fluid Dynamics is a complex discipline that crosses many disciplines “from wind and air movements around structures to blood and plasma interactions in the human body. Gilles Eggenspiele is a senior product manager for Pittsburgh-based ANSYS Inc.   DE spoke to Eggenspiele to better understand the application of ANSYS products for fluid dynamics modeling and simulation, and how such applications may benefit design engineers in the modeling of fluid systems.

DE: Is the fluid-structure (FSI) interaction a coupling of more than one ANSYS software application?

GE: ANSYS offers fast and accurate fluid and structural simulation tools, as well as an easy-to-use environment to seamlessly connect both physics in an automated workflow.

To perform an FSI simulation with ANSYS, engineers use two physics-dedicated solutions and the ANSYS Workbench environment, which manages all required connections. This allows for all relevant information to be seamlessly passed from one solver to the other.

Without ANSYS’ accurate and reliable solvers and FSI capabilities, performing an FSI simulation is a complex and time-consuming process. Engineers would have to manually manage different software “often from different providers “as well as the transfer of information from one solver to the other, etc. 

DE: Can you offer a few examples of which fluid systems work well with ANSYS Workbench?

GE: ANSYS Workbench is the simulation environment in which engineers can set up fluid simulation using computational fluid dynamics,  or CFD, software ANSYS Fluent or ANSYS CFX. Companies all around the world use ANSYS CFD software for a wide range of applications.

One example would be predicting the aerodynamics properties of a car or an aircraft: ANSYS CFD allows those companies to reduce drag “hence,  reducing fuel consumption. Other companies use CFD to design high-performance internal combustion engines or to enhance the safety of nuclear reactors. Its multiphase capabilities help engineers design ships that can withstand extreme weather conditions. It is interesting to note that many clients are now also performing design exploration or optimization; they are performing hundreds of simulations automatically thanks to the ANSYS Workbench automatable workflows. 

Clients are taking advantage of our CFD software to explore many design possibilities to optimize the performance and robustness of the product. For example, a client recently used data from more than 1,200 separate simulations conducted with ANSYS multiphysics software to replicate the dynamic pressures of a competitive atmosphere in a risk-free virtual environment. These simulations helped engineers address real-world design concerns, and provided the necessary insight to identify the optimal product design “all while reducing time to market. Physically testing such a large number of design iterations would be nearly impossible.

DE: Is your software routinely used to develop interactive models to predict outcomes and identify risks?

GE: Yes, this is one of the key reasons why engineers use our software. Any time during the simulation process, the user can modify a geometry or operating condition to answer “what if” questions. For example:  What if the geometry of the product is changed? What if the product is used under different conditions than anticipated? Using simulation to develop better products is not about analyzing a single design; it’s about both interactively and automatically analyzing hundreds of design iterations in many different operating conditions “and ultimately, creating the one that will deliver the best performance.

Jim Romeo is based in Chesapeake, VA. Contact him via [email protected].