Effect of frequencies on the change of electrical impedance in sand dunes of Ouargla region

Abstract

In this paper, we put the accent on the measurement of real and imaginary parts of electrical impedance and effective loss tangent respectively z′, z″ and tgδ in sand dunes of Ouargla region at a range of frequency intervals between 4,6849×10−2 Hz and 1,8593×10+6 Hz with AC voltage of 1.000 V using the impedance spectroscopy. The experimental results revealed that the real and imaginary parts of electrical impedance and effective loss tangent have strong frequency dependence. In the frequencies range (4,6849×10−2 – 4,9385×10−1) Hz z′ < 0 and z″ change between (4,8118×10+2 × 5,0422×10+1) Ω, in the frequencies range (5,4877×10+1 – 2,3426×10+4) Hz z′change between 146,04 Ω and 4,8193 Ω and z″<0. In high frequencies range (1,2599×10+5 – 1,8593× 10+6) Hz z′ change between 4,5359 Ω and 5,0567 Ω. The effective loss tangent values increase until they reach a peak, in frequencies range between 4,6849×10−2 Hz and 2,5197×10−1 Hz, but then the remaining frequency the values decrease until they become constant. The nature of impedance electric variation indicated a possibility to knowledge the polarization of sand dunes of Ouargla region and acquaintance the frequencies when the material is passive devices or active devices. It is also possible to know the quality of equivalent electrical circuit, whether it is induction or capacitance.