Fluidan’s patented technology
RheoStream® is based on a new and patented measuring principle, combining two flow cells.
A precision pump in the instrument controls the flow rate of the sample as it is passed through the two flow cells.
This is how it works
In each of the flow cells a differential pressure is recorded – these pressure signals are the primary measurements, which are analyzed and converted into the rheological parameters.
The pump controlling the liquid flow is a precision syringe pump: During sample intake the pump is filled (e.g. 5 ml of liquid) and then it empties by pushing the liquid through the flow system.
The pump operates in pules or steps, each securing a precisely determined shear rate in the flow system.
A typical measurement consists of 3-8 such pulses, giving 3-8 points on a flow curve (corresponding values of shear rate and viscosity).
At the same time, the patented design of the complex flow cell produces pressure signals that can be correlated to the viscoelastic properties of the liquid, each flow rate corresponding to a frequency.
This video illustrates the liquid flow in the instrument: https://fluidan.com/3d-video-shows-how-rheostreamworks/
RheoStream VE measures the key characteristics of liquids: Shear thinning, apparent yield stress and viscoelasticity.
RheoStream VE reads out:
- Flowcurve/viscometry data:
- shear stress and viscosity across a range of shear rates
- model based rheology characteristics: Power law: n, K; Bingham and Hershel-Bulkley: Yield stress (σ0) as well as n, K
- Viscoelasticity data:
- G’ , G’’ , G*, tan(δ)
- G’: elastic (storage) modulus
- G’’: viscous (loss) modulus
- G*: Complex modulus
- G’ , G’’ , G*, tan(δ)
tan(δ): tangens of phase angle
Fluidan ApS
CVR: 36392355
Address
Diplomvej 381
2800 Kgs. Lyngby
Denmark