Testing the Performance of the Low Viscosity Probe: Pure Water Experiment

In our last blog entry we introduced the φ1.5mm aluminium alloy low viscosity probe, a top performer in the measurement range of 0.1~1000mPa・s. This time around we would like to present the findings of our experiment testing its performance when measuring pure water versus that of the φ2.0mm aluminium general use probe (measurement range: 0.1 ~ 100,000 mPa・s).

Instrument Settings and Experimental Conditions

Motor Rotation Speed: 600rpm

Sample temperature: 20°C

Measurement time: 1 sec per measurement

Number of measurements: 100 for each probe

Sample: Pure water

Sample size: 0.3mL

Measurement Results

φ2.0mm aluminium genral use probe (optimal meas. range: 0.1~100,000mPa・s)

φ1.5mm aluminium alloy low visc. probe (optimal meas. range: 0.1~1,000mPa・s)

Average: 1.531mPa・s

Average: 1.037 mPa・s

SD: 0.01870 mPa・s

SD: 0.00568 mPa・s

RSD: 1.22%

​RSD: 0.55%

The theoretical value of water’s viscosity at 20°C is 1.002 mPa・s. After 100 measurements, the average viscosity attained for water when using the general use probe was 1.531mPa・s, and the RSD of the data was 1.22% (RSD is a statistic expressing data variation; the higher the value, the higher the variation). For the low viscosity probe the average viscosity was 1.037mPa・s with an RSD of 0.55%. As you can see, measurement values gained with the low viscosity probe are much closer to the theoretical value of water than those gained with the standard probe. Additionally, the low viscosity probe’s results were more consistent in this very low measurement range. As mentioned in our last blog, the particular size and composition difference of the probes make them more suitable overall for their respective recommended measurement ranges.

This experiment showed that using the EMS-1000S and the low viscosity probe made it possible to achieve very stable measurement results of water that come in very close to its theoretical value, a considerable achievement in the ever-challenging low viscosity range!

The smoother surface finish of the aluminium alloy low viscosity probe, along with its smaller size, allows better performance in lowly viscous substances such as water, ink and blood, as interfering forces, most notably friction, can be optimally minimized while still achieving a stable spin of the probe which is necessary for successful measurement.


We hope that you enjoyed the blog!

If you would like to learn even more about the scientific background of the EMS technology, please check out the measurement principle found here.

In the next blog article, we will present the results of our experiment comparing the standard and low viscosity probes in the measurement of inks.

If you would like to know more about the EMS-1000S Viscometer, please feel free to contact us by clicking the yellow “contact” button at the top of the page. Thank you for reading!