In-flow testing of a cylindrical dielectric sensor for measuring the sugar concentration of sugar beet syrup

Document Type : Research Article


1 M.Sc. Student, Department of Mechanical Engineering of Biosystems, Shahrekord University

2 Assistant Professor, Department of Mechanical Engineering of Biosystems, Shahrekord University


This study was aimed at measuring the sugar concentration of in-flow sugar beet syrup with degrees of Brix of 26.5, 37.9, 48.7, 54.1 and 62 at two flow rates of 0.02 and 0.04 l/s using a cylindrical dielectric sensor. The sensor consists of a steel cylindrical tube and a central core as the capacitor electrodes connected to a function generator and spectrum analyzer via coaxial cables. The sugar beet syrup fills the sensor from the bottom inlet and flows out from the top outlet. The effect of temperature within the range 25-75 ˚C on the dielectric constant of sugar beet syrup was investigated in the frequency range of 0-150 MHz. The results showed that the dielectric constant of in-flow syrup was larger at the flow rate of 0.02 than at 0.04 l/s. The temperature tests indicated that only the frequency of the second resonance is affected by the temperature with a decrease of dielectric constant with increasing the temperature. It was concluded that the dielectric sensor developed in this study can be implemented as a potent and accurate sensor for in-flow (in-line) measuring the sugar concentration of sugar beet syrup.


Main Subjects

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