For over 10 years, SIKA has been successfully developing and distributing vortex flow meters based on the Kármán vortex street. This is a very reliable measurement principle that is used in many applications.
However, new technical possibilities are now opening up in an important target application. Up to now, heat pumps have predominantly employed vortex flow sensors of nominal diameter DN20. Many market leaders in this sector rely on the SIKA flow meter with a measuring range of 5 to 80 l/min, since it meets all requirements.
However, by using more efficient circulation pumps within the heat pump, it can be controlled even in the low flow range. This makes the overall system even more efficient, which not only saves on heating costs but also further reduces the negative impact on the environment.
SIKA has improved on a tried-and-tested solution by developing a new Low Flow vortex flow sensor. This sensor also has a nominal diameter of DN20, but takes reliable measurements as of a flow rate of just 2 l/min. This is the perfect match for the new generation of heat pumps.
How did we do it?
A flow sensor’s measuring span is calculated by dividing the start value of the measuring range by the end value. With vortex flow meters, a measuring span of approximately 1:20 is possible.
For the measuring range start value of 2 l/min, a maximum flow rate of 40 l/min would have been possible with our previous technical capabilities. However, this is not enough for use in a heat pump, which is why we developed an innovative design incorporating all of our expertise and know-how. The result is the vortex flow sensor VVX20 Low Flow. With a measuring range of 2 to 65 l/min, we achieved a measuring span of 1:32.
The basis for this innovation is our patented pre-swirlers, which are already used in the SIKA vortex flow sensors with nominal diameters DN32 and DN40. They cause a slight turbulence in the laminar flow, so that vortices are formed even at lower flow velocities, making it possible to measure at lower flow rates.
In addition, the vortex flow meter VVX20 Low Flow has been given a new and patented internal design that increases the flow velocity in the sensor, which has further optimised the start of the measuring range. And this is achieved without significantly increasing the pressure drop.
You can read more about the vortex flow sensor VVX20 LowFlow here.