CFD Analysis of a Stratified Storage System
The new OpenFOAM® investigation buoyant driven flows created during summer 2020
After the website release in June 2020, I decided to investigate an old topic called »stratified storage system«. A few years ago (around 2014), I tried to simulate the layering inside a heating storage tank without success. Since I gained a lot of knowledge in the last few years, I re-investigate the topic as I also do have a new working station (Threadripper Gen. 3 with 32 cores), which allows me to create a more complex and realistic system. A stratified vessel system commonly uses simple physics to store hot water intelligence. The vessel works as follows: Hot new air is inserted in the bottom region of the storage tank. The hot injected water enters a subsystem that allows infused water to flow upwards the vessel - due to the buoyancy effect - until it reaches the correct temperature region (height). In that height, it leaves the subsystem in the vessel and enters the storage tank via the port.
Temperature-Dependent Thermophysical Properties for Pure Water
The OpenFOAM® thermophysicalProperties file for water (polynomial approach)
Water is an essential fluid in our world. Even in computational fluid dynamics, it is a characteristic fluid that appears in many analyses. In some cases, one needs the buoyancy effect or temperature-related data, and hence and therefore, temperature depended data are required. I also had a few calculations that need temperature-dependent water properties. In OpenFOAM®, we can use the polynomial approach for temperature-dependent physical property data. However, I always had to derive them again and again, as I forgot to save the file to an appropriate location where I can find them. Fortunately, I found the data during the website-relaunch. Therefore, I decided to put the polynomial derivation into my blog for two reasons: (a) I know where to pick it up fast, and they will not vanish anymore, and (2) everybody can use it. The polynomials are based on pure water in the range between 0 °C < T < 100 °C at atmospheric pressure 101325 Pa.
