Abstract

In this study design and operation of a capacitive cell sensor for liquid mixture monitoring is reported. Operation of the capacitance measurement module for such probe is based on the charge and discharge method. The capacitive effect of small drop of different liquids in tap water was studied using this capacitive sensor. A small percentage of contaminating agents such as oil in tap water is determined with a good sensitivity. Comparison of the measured resistances for different liquid mixtures shows a decrease by increasing Total Dissolved Solids (TDS). In another study the electrical capacitance of different solutions, mixture of ethanol and water, mixture of methanol and water, mixture of petroleum and water and other liquid mixtures were studied. It must be pointed out that the measuring capacitance of the sensor is different from that of the liquid capacitance, but the samples electrical characteristics can be compared relatively with each other. The effects of the electrical conductivity on the permittivity and conductance of different liquid mixtures are also investigated. The experimental results are promising concerning water liquids and verify the successful operation of such device as a liquid sensor and are a useful method for checking the electrical quality of the water mixture that is required for different applications.

Keywords:

Capacitance measurement, electrical conductivity, electrical properties, liquid mixture, sensor,

References

1. Ahn, H., K. Kim and H. Han, 2005. Nonlinear analysis of cylindrical capacitive sensor. Meas. Sci. Technol., 16: 699-706.
   CrossRef    
2. Ashrafi, A. and H. Golnabi, 1999. A high precision method for measuring very small capacitance changes. Rev. Sci. Instrum., 70: 3483-3486.
   CrossRef    
3. Fasching, G.E., W.J. Loudin and N.S. Smith, 1994. Capacitance system for three-dimensional imaging of fluidized-bed density. IEEE T. Instrum. Meas., 43(1): 56-62.
   CrossRef    
4. Golnabi, H., 1997. Simple capacitive sensors for mass measurements. Rev. Sci. Instrum., 68(3): 1613-1617.
   CrossRef    
5. Golnabi, H., 2000. Guard-ring effects on capacitive transducer systems. Sci. Iran., 7: 25-31.
   
6. Golnabi, H. and P. Azimi, 2008a. Simultaneous measurements of the resistance and capacitance using a cylindrical sensor system. Mod. Phys. Lett. B, 22(8): 595-610.
   CrossRef    
7. Golnabi, H. and P. Azimi, 2008b. Design and performance of a cylindrical capacitive sensor to monitor the electrical properties. J. Appl. Sci., 8(9): 1699-1705.
   CrossRef    
8. Hach Company, 2001. Cat NO. 51800-18, Sension5 Conductivity Meter Manual.
   
9. Heidari, M. and P. Azimi, 2011. Conductivity effect on the capacitance measurement of a parallel-plate capacitive sensor system. Res. J. Appl. Sci. Eng. Technol., 3(1): 53-60.
   
10. McIntosh, R.B., P.E. Mauger and S.R. Patterson, 2006. Capacitive transducers with curved electrodes. IEEE Sens. J., 6(1): 125-138.
    CrossRef    
11. Strizzolo, C.N. and J. Cinverti, 1993. Capacitance sensors for measurement of phase volume fraction in two-phase pipelines. IEEE T. Instrum. Meas., 42: 726-729.
    CrossRef    
12. Tsamis, E.D. and J.N. Avaritsiotis, 2005. Design of a planar capacitive type senor for water content monitoring in a production line. Sensor Actuators A, 118: 202-211.
    CrossRef    
13. Woodard, S.E. and B.D. Taylor, 2007. A wireless fluid-level measurement technique. Sensor Actuators A, 137: 268-278.
    CrossRef    
14. Zadeh, E.G. and M. Sawan, 2005. High accuracy differential capacitive circuit for bioparticles sensing applications. Proceeding of the 48th Midwest Symposium on Circuits and Systems, Covington, KY, 2: 1362-1365.
    CrossRef    

Competing interests

The authors have no competing interests.

Open Access Policy

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Copyright

The authors have no competing interests.