The art of engineering can often be in finding pragmatic ways to use technology to solve real problems. While simulations may include an ever-increasing amount of geometric detail, it is not enough to simply generate ever finer meshes and use ever smaller time resolution. Simulations must still be solved in a reasonable time (and perhaps the one constant here has been that reasonable almost always means ‘overnight’). Therefore, until there is a dramatic breakthrough in computing power, modeling fluid flow will require engineering pragmatism in problem-solving for many years to come. But that need not be shouldered by the CFD engineer alone — ANSYS simulation software can support them in their efforts. ANSYS 15.0 contains multiple examples of how pragmatic approaches to efficient and effective simulation are contained in the software itself.
One such example is the dynamic combustion mechanism reduction capability in ANSYS Fluent. By automatically reducing the mechanisms to only the most important, dramatic reductions in simulation time can be achieved without the CFD engineer having to spend time and effort determining how to represent complex reaction mechanism in a simplified manner that models the behaviour sufficiently well. Instead, this pragmatism is built into the ANSYS software! Combined with further enhancements in ANSYS 15.0, it makes combustion simulation with even the most involved chemical reactions viable.
Another example is the interaction between fluid flow and structural behaviour in rotating machinery such as compressors and turbines. While simulating that interaction in its full transient detail may be technically possible, various realities make it impractical – not least the disparate timescales of flow phenomena compared to those of the structure. So again, a pragmatic approach is required – and ANSYS aids the CFD engineer here, too. Users can take advantage of the transient blade row model abilities in ANSYS CFX to simulate the unsteady periodic flow in a fraction of the time otherwise necessary, and then easily and efficiently transfer the predicted blade surface loads to a forced response analysis in a subsequent structural simulation to assess aero-elasticity – thanks again to new capabilities added in ANSYS Release 15!
A third example is the ability to capture heat transfer through fabricated solid structures made of multiple layers of different materials, each with its own thermal properties, without having to model each layer three-dimensionally. ANSYS Fluent’s new multi-layer shell conduction modelling capability allows users to save significant time and effort, as they can reduce the resolution of each layer to two dimensions without making sacrifices in accuracy. This allows users to incorporate heat transfer phenomena through fabricated solid components with both the required fidelity and the necessary efficiency, in applications for industries ranging from automotive to aerospace.
The wall film model in ANSYS Fluent is similar in the sense of being pragmatic, in that it also allows an economical yet sufficiently accurate two-dimensional representation of thin liquid films as part of larger models. With ANSYS 15.0, the applications for this this capability are expanded even further, with support added for its use in simulations with rotating components as well as with condensation and evaporation in combination with multiphase models.
These are but a few examples showing how ANSYS helps engineers with their constant drive to find pragmatic solutions to solve real problems. Many more are in ANSYS 15.0, and many more will continue to be part of each ANSYS release, to make sure engineers can put their problem-solving abilities to the best use possible!