Dielectric Kit for Vials @2.45GHz
The Dielectric Kit for Vials (DKV) is a new device designed to measure the complex permittivity of a wide range of liquid, granular or powdered materials around the ISM microwave frequency of 2.45 GHz.
DKV is a standalone equipment including all necessary components to perform automatically the generation, control and analysis of microwave signals, accurate calculation of dielectric properties and display of results. Everything in less than 5 seconds!!
Microwaves are emerging as an innovative, cost-effective, and efficient technology in various technological and scientific fields as chemistry, pharmacy, material science, food, agriculture, etc. Consequently, there is an increasing demand for accurate dielectric measurements of materials, to investigate new effective and efficient ways to apply microwave processing to their materials and reactions. Dielectric properties, particularly the loss tangent (imaginary part of the complex permittivity), determine the ability of materials to absorb microwave energy and convert it into heat. DKV is oriented to researchers or specialist that are interested in fast, reliable and traceable data of dielectric properties of materials, and they are not experienced with the use of sophisticated network analysers and microwave measurements.
Experimental setup
Operation principle
A sample of the specimen under test is placed inside a laboratory vial (i.e. pyrex, polypropylene or quartz) and introduced in the microwave probe though a hole at the top. Dielectric properties of the sample are calculated from the resonance response of the cavity (resonant frequency and Q-factor) (with and without the sample?) measured by a in-house Vectorial Network Analyzer (VNA) and the electromagnetic modelling of the probe geometry by a rigorous numerical procedure. DKV is provided completely calibrated, so there is no need of additional adjustments with reference liquids or other materials.
The Vials Dielectric Kit is fully controlled by a Labview-based software, which has been developed to perform all the necessary functions with a user-friendly interface.
The method is able to measure a wide range of dielectric materials covering values of dielectric constant (ε’) between 1-100 and loss factor (ε’’) between 10-3 to 101 (4 orders of magnitude!)
The estimated accuracy obtained for the dielectric constant is within the range of 1.5% in all the covered measurements, regardless of material losses. The error in the loss factor is constrained around 5% in all the considered measurement range.
Additional Options
DKV with vials (8 ml), External heater for measurements of dielectric properties with temperature, DKV Open-ended Coaxial tip, DKV for flat materials, The dielectric probe is an aluminium resonator
