LIQUIDS FILLING

Stress Engineering has used computational fluid dynamics to simulated liquids filling in a wider variety of industries, including pharmaceuticals, foods, skin care products, and cleaning products. Using CFD simulation we have helped our clients to optimize their filling processes so as to increase throughput while reducing or even eliminating foaming.

The plots below show the results of three different fill-rate profiles. In each plot the red area is liquid while the blue is air. The left-hand plot shows that filling at a constant rate causes severe splashing which will entrain air in the liquid and cause foaming. On the other end of the spectrum, filling can be done over the same period of time by starting from zero flow rate and ramping up to a high rate at the end of the filling cycle. The results of this process are shown in the center frame. In this case the high flow rate required at the end of filling causes a depression to be blown into the surface of the liquid. This forces air into the pool of fluid already in the container and generates foaming. The results in the right-hand frame show the preferred filling profile. In this case the filling rate is low at the beginning and steps to a higher rate 20% into the cycle. This lays a pool of fluid into the container at low speed to avoid splashing. This pool cushions the later high-speed flow. With proper profiling of the fill rate the package the throughput can be maintained and foaming can be avoided.