New flow technologies using integrated sensor functionality

Customers over the world are searching for simplication and integration of their gas, liquid or vapour flow processes. They prefer integrated platforms that are compact, robust and reliable, and even containing different type of sensors.

In this blog I provide a sneak-preview of the ‘toolbox’ which is currently in development at Bronkhorst. One of the components which we are working on, a micro Coriolis mass flow sensor, is already shared with you in our previous blog ‘Miniaturization to the extreme’.

Multi-parameter sensor chip

An example of how a program was started to minimize the footprint;
Bronkhorst received the request to measure fysical gas properties in combination with several partners. The fysical properties included the:

• heat capacity (cp)
• density (ρ)
• thermal conductivity (λ) and
• viscosity (η)

 
To analyze these properties several individual sensors like a Coriolis-, Thermal-, Pressure- and Density sensor where needed. To proof  that the combination of several sensors in combination with electronics  could meet the needs of the customer, a demonstation model was developed. This demonstration model contained commercially available products which where combined in one system. 
 

The learnings from the demonstration model support the project team to define the exact scope for the multiparameter chip alternative. 

One important aspect of sensor performance is the stability, espacially when multiple sensors are combined to determine information about the medium in the system. In figure on the right it is shown that we can measure the viscosity with a combination of the massflow, density and differential pressure.
With the demonstration model shown above we have tested if the viscosity of a medium can be measured accurately over longer periods independend room temperature changes.  The measurement of viscosity can be interesting for some applications, for instance with natural gas  where viscicosity and calorific value are strongly correlated.  The test results shown are for a test period of 84 hours, the histogram shows that all measurements values for the viscosity fall within a band of 0.5 %.
  

Future state sensor

The next level will be to combine the same functionalities on a much smaller footprint. The concept below shows the possibities to combine the required parameter on chip level.