We encounter pumps in our everyday life in all manner of applications, be it in our dishwasher or car; or indirectly in water supply, oil pipelines, cooling water pumps and many more applications. In fact, the very significant fraction of the world’s energy used for pumping may well surprise you - and therefore the potential opportunity for improved pump design to deliver big savings (both in dollars as well as greenhouse gas emissions), a point which hit home to me this week when I watched a recent webinar on using ANSYS 17.0 to model and optimise pumps and other turbomachinery.
At LEAP, our engineers watch many different webinars but I found this one particularly captivating as it clearly showed the entire pump design process from start to finish: starting with the sizing tool ANSYS VISTA-CPD, turbo-specific geometry tools – showing creation of the inlet and outlet regions using ANSYS BladeModeler, and then how easily turbomachinery geometries can be meshed automatically in ANSYS Turbogrid (something that all customers now have access to via any ANSYS license containing access to a meshing task!).
The webinar then went on to show the use of ANSYS VISTA-TF to perform 2d mean-line simulations to estimate the pump characteristics, as well as providing an initial guess for the 3D flow. The 3D flow setup in ANSYS CFX is made very easy, the solver is robust and efficient and the post-processing has many options specific to turbomachinery simulations, such as turbo mode in CFD Post and the pump macro template – which makes calculation of pump specific outputs easy and repeatable.
The webinar went on to explain the different ways to handle the rotation of the impeller – starting from the simplest steady-state approach, then the stage (or mixing plane) method to average out variation as the fluid enters the volute, and then finally to the new Blade Row Modelling tools that allow the entire pump to be modelled as a transient only keeping a pair of rotor and stator blades. This is truly unique technology in commercial software.
Next, there were demonstrations of cavitation (vapour formation in regions of low pressure) and also dissolved gas evolution – both of which lead to a loss in pump performance. Discussion of erosion, mechanical behaviour, … Finally, on the CFD front the various methods for modelling positive displacement pumps were outlined and some nice demonstrations were given.
The last part introduced many of the other ANSYS tools that are being used in the design and manufacture of pumping systems. These ranged from motor design, condition monitoring and using the Internet of Things to have remote access to performance data and being able to control pump operation.
If you are involved in designing, making, using or monitoring pumps – I feel that this is a must-see webinar. Even if you are not directly involved in this industry, I encourage you to watch it anyway as it is very well presented and you will no doubt learn something useful.