Metamaterial sensor for transformer oil, and microfluidics

Metamaterial sensor which is composed of split square rings to operate in X band for liquid and microfluidics has been proposed in this study. For measurement and simulation, we have designed and manufactured a sample holder for easy injection and measurement of fluids. Dielectric properties of the fluid samples have been changed according to the usage time, humidity etc. Proposed structure reacts to the dielectric constants of the transformer oil or the other microfluidics by resonance frequency which is also validated by simulation and testing. While 70MHz bandwidth change in the resonance frequency for transformer oil has been observed, it dramatically increases to 210MHz and decreases to 40MHz for methanol and olive oil adulteration. Reflection coefficient measurements for clear (unused) transformer oil, methanol and olive oil along with corn oil have been performed. Tested results are generally compatible with the simulated ones. Proposed structure, can be effectively used for liquids whose dielectric constant varying from 2 to 24. Simulation study shows us that the proposed structure gives 560MHz bandwidth when clear transformer oil is replaced with acetone. Implementation of transformer oil as well as microfluidics with high quality factor is the novel side of proposed sensor study.