Adaptive Control System for Optimizing the ECG Process under the Overcut Constraint
One of the main limitations 1n Peripheral Electro Chemical Grinding (ECG) is the overcut phenomenon. The dominant parameters which govern the dimensions of the geometrical overcut are the voltage and the feedrate. This paper deals with the development of an empirical model which describes the overcut as a function of the dominant parameters. Pased on this model an adpative control system was built and experiments in Profile Peripheral ECG were carried out. A comparison of the results obtained with and without the adaptive control system is presented as well as the relationship between the side and bottom overcuts. According to the above an adaptive strategy to control the geometrical overcut in Profile ECG is suggested.
Off-line multiresponse optimization of electrochemical surface grinding by a multi-objective programming method
Abstract The objective of this study is to optimize electrochemical grinding (ECG) process responses simultaneously by an off-line multiresponse optimization methodology. The responses considered as objectives are side and bottom overcuts, surface finish, spindle load, total metal removal rate, and wheel wear. Materials of 304 Stainless Steel are ground by the ECG process. The process variables optimized for the above objectives include electrolyte type, wheel material, grit size, grit concentration, d.c. voltage, electrolyte flow rate, wheel speed, feed rate, and ripple effect. A simple weighting method transforms the multi-objective problem into a single-objective programming format and then, by parametric variation of the weights, the set of non-dominated optimum solutions are obtained. It is shown in this paper that the multi-objective optimization methodology can be applied for an ECG operation, and that the optimal operating conditions for any given set of weights can be obtained depending upon the objectives.
Modeling of chemical reactors—XXIX mixing-cell model for packed bed reactors. Steady state considerations. Problems of multiplicity
Abstract The axial heat and mass transfer in tubular catalytic reactors may be described by mixing-cell model and diffusion model as well. The diffusion description yields for a strong exothermic reaction and adiabatic conditions three steady state profiles, on the other hand the mixing-cell model gives rise to more than three steady states. A simple numerical and graphical analysis for mixing-cell model is presented.