Tehnika (Jan 2014)

Solution and show thermodynamic problem by using mechanical and electrical analogies

  • Pejović Branko B.,
  • Mićić Vladan M.,
  • Tomić Milorad V.,
  • Damjanović Vladimir S.,
  • Ignjatović Mladen S.

DOI
https://doi.org/10.5937/tehnika1401069P
Journal volume & issue
Vol. 69, no. 1
pp. 69 – 75

Abstract

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In this paper, for the case of gas oscillator two characteristic thermodynamic change of state, and for them defined functional dependence of the force from moving the piston in a nonlinear form were considered. In this paper small oscillations are observed and the linearization is performed by neglecting nonlinear term as the small size at isothermal change and with development obtained function in Taylor series for adiabatic change. Based on the analysis of analog oscillator of mechanical system, or the equivalent scheme of problems, characteristics oscillation parameters and the motion law of the observed thermodynamic system are defined. With this procedure greatly simplifying for problem solution was achieved with respect to classical procedure. At the end of the paper, an analysis of the obtained results were done and appropriate electrical analogy was setting. This is used for the presentation of the problem through appropriate electric circuits and analogy mathematical relations, which involve voltage and electric currents as electric sizes. Also, it was shown that the electrical analogy can be used for all mechanical and thermodynamic processes which describes by homogeneous second-order differential equations which are the most common in technical practice.

Keywords