Parent Category: Products

Computational Fluid Dynamics:
CFD Simulation Software 

Computational fluid dynamics or CFD simulation software is a tool for the simulation of fluid flows using numerical analysis for computation. Engineers and analysts use CFD software to predict, how fluid flows will perform. To say it in simple words: if you would like to know, how fluid behaves in motion, you can find out with computational fluid dynamics software.

The market for CFD simulation software products seems to be opaque, especially when CFD is new for you. Maybe you are not sure, which software to choose for your issues. Or maybe the differences between the various CFD software products are not clear for you. To choose the right CFD simulation software can be tricky - but it's very important to choose carefully, if you want to use CFD successfully with serious results. 

One main criterion to distinguish the CFD Software products on the market is the solver with the underlying method. There are mesh-based (classical methods) and meshless methods. Before you decide to use a specific Computational Fluid Dynamics software you have to check amongst other things, which method meets your requirements better.

 

CFD Simulation Software -
which one is right for your requirements?

A short example for illustration:

Manufacturers of fridges use polyurethane (PUR) foam for thermal isolation of refrigerators. The PUR is injected directly into the hollow wall of the fridge, the foaming takes place in the cavity and fills it completely. 
For better understanding and optimization of the foaming process Computational Fluid Dynamics software can be a very helpful tool.

Before starting with CFD simulation, the fridge manufacturer could be interested in the following questions:

- which is the better method to simulate the PUR foaming process in a fridge with a complicated geometry?                                                      

- how do different production types for fridge manufacturing perform (number of inlets, moving pipe...)?

- how is the flow in the cavity?

- where might entrapments of air occur?

- how is the pressure of the polyurethane acting on the cavity?

 
In this article we take a look at the first question. Regarding the other questions you can find here more information about foaming fridge with PUR .

  

Mesh-based versus meshless methods 

Mesh-based methods

Mesh-based Computational Fluid Dynamics software products need a mesh to discretize the continuum domain. To build this mesh is a very time consuming and thereby expensive procedure - especially in a complicated geometry of a fridge with many small details (as gaps or cutouts).
The foaming of the polyurethane as a dynamic moving process is challenging for meshbased methods - the mesh that discretizes the flow domain has to be constructed again and again (remeshing), which takes a lot of time.

So, with this method it would take weeks to receive a satisfying simulation solution (if you receive a solution at all).  


Meshless methods

The Finite Pointset Method is a meshless code that is used in NOGRID Computational Fluid Dynamics software - it does not require a grid or mesh. Instead, it generates a local defined, non-stationary point cloud distribution for the discretization. The point cloud is very flexible (in comparison to a rigid mesh) and each finite point covers all fluid information (as density, velocity, pressure, temperature). The point cloud is generated automatically by the CFD software depending on the user's settings. Points are automatically filled, moved, refilled and cleaned depending on user specifications.

This method delivers solutions, where others must give up. It can excellently be applied in cases, where grid-based methods reach their limits due to the necessary remeshing.  It is strong in case of computing moving parts or in case of computing complex free surfaces and delivers solutions in a very reasonable time (compared to mesh-based methods) because of the rapid pre-processing (no need for remeshing). 

For this method the simulation of the PUR foaming in a complicated fridge geometry is no problem. The meshless CFD software handles free surface flow and moving parts in the flow domain and allows the simulation of any conceivable refrigerator geometry. The simulation can be performed in a short time and high-quality results give deep insights into the flow process of the PUR in the fridge (see figure 1).

 

Meshless Computational Fluid Dynamics Software from NOGRID 

NOGRID's CFD software provides solutions for simulation tasks in the wide area of flow and continuum mechanical problems. It's a tool with amazing flexibility, accuracy, reliability and robustness - it delivers high quality results for a wide range of fluid flow applications using an unequalled technology: Extremely short modelling time with a fast and robust solver based on a meshless code and an outstandingly short computation time in case of free surfaces or moving parts. The PUR foaming in a refrigerator is only one example - NOGRID's meshless CFD software covers a wide range of applications, where mesh-based methods would be the worse choice.

 

 CFD simulation software (Computational Fluid Dynamics) - PUR foaming fridge

Figure 1: CFD simulation software (Computational Fluid Dynamics) from NOGRID - PUR foaming in a fridge