Papers by Author: S. Narayanan

Abstract: This paper investigated the influence of filler materials such as E308L and ENiCu-7 utilized in the GTA welded AISI 304 with respect to mechanical and corrosion properties. It was found that E308L had shown better tensile strength and corrosion resistance as compared to ENiCu-7. A comparative analysis had been made on the different regions of the weldment subjected to cyclic air oxidation at 700°C. The corrosion products were examined using XRD and SEM/EDAX analysis.

Abstract: A method to predict the modal density and radiation efficiency of orthogonally stiffened cylindrical shell is presented in this paper. The modal density is derived using energy method from the undamped natural frequencies of stiffened shell by treating the stiffeners as discrete elements. The band averaged radiation efficiency is estimated by categorizing the structural modes into acoustically fast and acoustically slow modes. The predicted parameters are compared with experimental results using laser vibrometer measurements. Phase-roll off has been observed in laser vibrometer measurements for which a correction procedure is applied. This prediction method can be easily extended to shells with stiffeners having different size, orientation etc.