Experimental evidence for vibrational resonance and enhanced signal transmission in Chua's circuit

We consider a single Chua's circuit and a system of a unidirectionally coupled n-Chua's circuits driven by a biharmonic signal with two widely different frequencies \omega and \Omega, where \Omega >> \omega. We show experimental evidence for vibrational resonance in the single Chua's circuit and undamped signal propagation of a low-frequency signal in the system of n-coupled Chua's circuits where only the first circuit is driven by the biharmonic signal. In the single circuit, we illustrate the mechanism of vibrational resonance and the influence of the biharmonic signal parameters on the resonance. In the n(= 75)-coupled Chua's circuits enhanced propagation of low-frequency signal is found to occur for a wide range of values of the amplitude of the high-frequency input signal and coupling parameter. The response amplitude of the ith circuit increases with i and attains a saturation. Moreover, the unidirectional coupling is found to act as a low-pass filter.Comment: 15 pages, 12 figures, Accepted for Publication in International Journal of Bifurcation and Chao

Enhancing performance measures in Electrical discharge Machining of Monel 400TM using Mixture of Dielectric fluids

Electrical discharge machining (EDM) process is a most reliable technology to machine wide varieties of materials to required complicated shapes, since it is widely used in aerospace, automotive, mould making, tool and die casting industries. Many researchers have strived to improve the performance of EDM process by introducing various tool materials, dielectric fluids and additives, despite the machining efficiency of this process being much less than conventional machining processes. In general, commercial grade EDM oils is conventional dielectric fluids in electrical discharge machining (EDM) which offer more tool wear rate and poor surface finish. The cited drawbacks could overcome by developing mixture of dielectric fluids. The mixture is developed by using EDM oil and servotherm. It is proposed experimentally obtain the best proportion of Commercial grade EDM oil–servotherm and observing its performance in EDM of monel 400TM. Sixteen samples of Commercial grade EDM oil–servotherm of different proportions were employed during the study. The best of EDM–servotherm observed was 85:15, which yielded in the highest material removal rate (MRR) as than other proportions and tool wear rate (TWR), and surface finish (SR) are found to be not satisfactory as comparing EDM oil alone. This study may be more beneficial to automotives components manufacturing sectors for making the components with less machining cost with good quality of the products