Simulation Fluid-Structure Interaction Elastic Beam

In this study we present the simulation of a Fluid-Structure Interaction (FSI) case with an elastic beam. In engineering, fluid-structure coupling or fluid-structure interaction refers to the consideration of the mutual influence of structure and flow. The mutual influence of structure and flow is an interesting phenomenon that often occurs in nature and technology. It occurs on deformable and/or movable structures around or through the fluid flows. The structure deforms under the forces imposed by the flow. In the case of highly deformable structures, the flow is very often disturbed by the structure and thus influenced. In this case, there is a real, two-sided fluid-structure coupling.

Figure 1: Setup FSI elastic beam case within NOGRID points

Figure 2: Deformed elastic beam (red color) at steady state

Figure 3: Temperature plot with velocity vectors for the elastic beam at steady state

Figure 4: Animation of the FSI elastic beam

In this simple 2D example an elastic beam is located within a fluid channel. The fluid flows from left to right and imposes forces on the elastic beam. The elastic beam starts to deform until a steady state between fluid and solid forces is reached.  The simulation is solved fully coupled using the Lagrange method. Fully coupled means the stress within the beam and the fluid variables for velocity and pressure are solved simultaneously in one big solution matrix. The Euler method is also available to solve this case. 

In addition to stress, velocity and pressure the temperature is computed for both structure and fluid as well. In figure 4 you can see the evolution of the deformation and the temperature over time until a steady state for the deformation and for the temperature is reached.

This model can act as basis for more complex structures and will give you a better understanding of the fluid structure coupling and helps to improve your design regarding efficiency and costs.

NOGRID points can perfectly be used for designing and problem solving for all kinds of FSI processes. The structure deformation, the temperature and the cooling/heating rate can be predicted. NOGRID points helps to understand the flow by visualization of the mass, momentum and heat transfer of single and multiple phases. You receive integral quantities which you can use to analyze the FSI process efficiency.

NOGRID unites abilities to handle FSI problems and allows the simulation of any conceivable geometry and operation modes such as

  • computation is in full 3D solving complete Navier-Stokes-Equations
  • easy and intuitive setup also for FSI (Fluid-Structure-Interaction) cases
  • free definable material properties by equations or curves
  • evaluation of chemical reactions and corresponding heat source terms
  • open or closed domains including inflow and outflow areas (non-batch mode)
  • moving of parts 

Nogrid's strengths

Particular strengths of NOGRID's fluid flow CFD software are the rapid preprocessing (no fluid grid needs to be generated, only the boundary mesh, inner finite points are generated automatically depending on User setting initially and during computation), and the outstandingly short computation time even for complicated cavities.
As you can see in the image below, the boundary of the geometry still requires a mesh to allow the interior finite points to detect the boundary. The boundary must therefore be meshed and the finite points inside are automatically generated during the simulation controlled by User specifications.
Easy Modelling

Easy and fast modelling: Build geometry, mesh boundary, setup the case and start computation

What is CFD from NOGRID?


CFD solves the fundamental equations that define the fluid flow process. With CFD software from NOGRID every engineer makes better decisions by predicting, analyzing and controlling fluid flow, heat and mass transfer or chemical reaction. By using NOGRID software for flow modeling you receive information on essential flow characteristics as for example flow distribution. Using it additional to testing and experimentation NOGRID software helps to improve the evaluation of your design – resulting in better construction and operation parameters, increasing planning security and money savings due to faster time to the marketplace for your product or process.




With NOGRID, you choose professional CFD software and services – our aim is helping you to be successful. When you decide to work with NOGRID you choose close cooperation with a dynamic, flat hierarchies-organization. Short information channels result in quick and accurate professional support and service. Our team consists of highly qualified employees, who are experts in fields such as numerical simulation or computational fluid dynamics. Based on our know-how, we are pleased to offer the following services, responding to your individual requirements:




In our two-days training courses you will learn, how to use NOGRID CFD software efficiently. Our technical support team will teach you how to handle and solve different cases.

For more details please refer to Training Courses →


Technical Support


We offer full professional support from the minute you start using our software, by telephone or by email. Contact us, when ever needed.

For more details please refer to Software Support




Lack of time or resources and other constraints often make outsourcing an attractive solution. We help you with your flow modeling needs. Based on our engineering expertise in this field we offer individual numerical simulation services matching the unique needs of your organization.

For more details please refer to Simulation Services →


Göttelmannstr. 13B
55130 Mainz, Germany

Simulation Software from Nogrid

Follow Us: