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The lid-driven cavity problem is of high importance in fluid dynamics serving as a benchmark for the validation of CFD methods as well as for studying fundamental aspects of incompressible flows in confined volumes driven by the tangential motion of one or more bounding walls. In this article, capabilities of PreonLab in capturing 2-D flows inside a cavity are evaluated for different Reynolds numbers.

With the release of version 5.0, PreonLab saw several additions to it, ranging from new features to under-the-hood developments. They play an important role for wading simulations, which can be broadly classified as follows: Performance & Accuracy: Adaptive simulations with up to 3 particle levels Faster Pressure Solver Usability: Object Grouping Improvements in the Plot Dialog Improvements in the Connection Editor Connect sensor right-click action

Piston Cooling Jets (PCJs) are used in traditional Internal Combustion (IC) engines to remove the excess heat from the piston, allowing for higher thermal loads to be reached. PreonLab 5.0 allows for investigations of the dynamic and thermal interactions between the lubricating oil jet and the moving piston.

For coarsely-resolved simulations, especially those for applications that require numerous quick design iterations to asses the plausibility of a design, a simulation that both runs quickly and delivers results in the correct ballpark is needed. The coarse resolution allows for fast computation, but such simulations tend to suffer from gradient underprediction at the walls. This happens in particular for flow regimes which may be considered as turbulent, where the steep gradients at the wall mean that a very fine resolution is required to correctly reproduce them. With the effect of wall-bounded phenomena (e.g. wall shear stress, wall heat flux) being a key result for studies that such simulations are used for, it is clear that there is potential for improvement here.

Being one of the flagship applications of PreonLab has made it important to offer various post-processing possibilities to address the needs of the users when it comes to water wading simulations. You can gain loads of insight by performing a full wetting analysis, measuring the flooding height, predicting under-body forces and understanding the flow paths for the regions of interest as well as measuring flow rates of water entering the engine compartment or any critical part of the vehicle.

It’s finally here! PreonLab 5.0 is a massive update and we couldn’t be more excited to share it with you. Are you ready for the next level? Here is why this major release is a leap forward in efficiency, usability and reliability: Adaptive Resolution: PreonLab 5.0 adds a third particle level and greatly improves the quality and efficiency of adaptive simulations. This enables unprecedented speedups for a broad range of applications. User Interface Update: Once you start PreonLab 5.0 for the first time, you will not want to go back. But this release does not only introduce a fresh and beautiful look, it also includes a number of changes that will accelerate your workflow. Thermodynamics: The new (experimental) conjugate heat transfer capability allows you to tackle even more applications with PreonLab. Furthermore, the new wall functions enable more accurate thermodynamics simulations. Snow Solver: PreonLab 5.0 improves complex snow dynamics with dramatic increases in accuracy and efficiency. Make sure to follow us on LinkedIn so that you don’t miss new videos, case studies and updates!

In the article, Adaptive Particle-based Simulation in PreonLab, we showed that a simulation with two particle levels can accurately reproduce the results of a simulation with higher uniform resolution. But delivering a good result is not enough – for the system to be useful it must also deliver this result faster than the uniform simulation. The adaptive simulation will always have fewer particles, but this does not necessarily mean that it will be more efficient overall. Splitting, merging and correction (see the last article) represent a significant effort and can outweigh the reduction in particles. Is the cost worth it?

Particle-based fluid simulation methods such as implicit SPH have many advantages over Eulerian grid-based methods. You can read all about it here. One advantage that Eulerian approaches still enjoy over most particle-based solvers is the ability to model fluid adaptively. By using finer cells in regions of interest and coarser cells in others, an adaptive mesh can reduce computational effort by several orders of magnitude. If multiple levels of detail are so clearly beneficial, why are they still relatively rare for most particle-based solvers? Disclaimer: This article shows simulation results that were produced with an internal beta of the upcoming PreonLab 5.0 and are not perfectly reproduceable in PreonLab 4.x or earlier.

With PreonLab 4.3 we have just released the last update for our 4.x lifecycle. This release is again packed with great new features that will help you to enjoy your daily work with PreonLab even more: Keyframe Looping: This will lift keyframing to the next level. Keyframe looping makes defining recurring motion a pleasure. Volume Source: In PreonLab 4.3 you can now specify the exact amount of fluid that needs to be generated inside a geometry. The improved Volume Source will do exactly what you tell it to do. Performance: We have improved the scalability of some components that previously didn’t perform optimally with many cores and many MPI nodes. Most notably, this includes local refinement, multiphase simulations, the snow solver and the implicit viscosity solver. Usability: We turned searching statistics in the Plot Dialog from beast to beauty and added the ability to choose for the unit of a specific statistic. You will also enjoy the improved workflow when selecting multiple objects in the Property Editor. Snow Solver: Presets ahead! With the new snow presets you can choose from several different snow variants. Furthermore we have been working on the performance of the snow solver – make sure you fastened your seatbelt. Furthermore, PreonLab 4.3 also introduces improvements of the Airflow import, the Car supension model, the Heat Flux sensor and many more. Check the changelog for a comprehensive list of all the great stuff you can expect from PreonLab 4.3. Make sure to follow us on LinkedIn so that you don’t miss new videos, case studies and updates!

We are excited to announce the release of PreonLab 4.2 – the answer to life, the universe and everything! It also contains many new or improved features that will help you to find answers to your more specific CFD-related questions: Mesh-based height sensor: The new sensor measures the height of fluid (or snow) above surfaces. Improved user interface: With updates to the connection editor, the scene inspector and the on-screen display, PreonLab 4.2 looks and feels better than ever. Optimized local refinement: Better performance and the introduction of user-defined domain shapes facilitate the acceleration of even more applications with local refinement. Improved volume source: Improved volume source: The volume source now fills more accurately, minimizing artificial movements after the initialization. Furthermore, PreonLab 4.2 also improves the snow solver, adds the Herschel-Bulkley viscosity model for non-Newtonian fluids, enhances the car suspension model, accelerates performance in scenes with large geometries, introduces new rendering capabilities, reduces memory consumption and improves the airflow import. Make sure to follow us on LinkedIn so that you don’t miss new videos, case studies and updates!