Apurba Kumar Roy

Effect of Hole Shapes, Orientation And Hole Arrangements On Film Cooling Effectiveness

In this present work, the effect of hole shapes, orientation and hole arrangements on film cooling effectiveness has been carried out. For this work a flat plate has been considered for the computational model. Computational analysis of film cooling effectiveness using different hole shapes with no streamwise inclination has been carried out. Initially, the model with an inclination of 30° has been verified with the experimental data. The validation results are well in agreement with the results taken from literature. Five different hole shapes viz. Cylindrical, Elliptic, Triangular, Semi-Cylindrical and Semi-Elliptic have been compared and validated over a wide range of blowing ratios. The blowing ratios ranged from 0.67 to 1.67. Later, orientation of holes have also been varied along with the number of rows and hole arrangements in rows. The performance of film cooling scheme has been given in terms of centerline and laterally averaged adiabatic effectiveness. Semi-elliptic hole utilizes half of the mass flow as in other hole shapes and gives nominal values of effectiveness. The triangular hole geometry shows higher values of effectiveness than other hole geometries. But when compared on the basis of effectiveness and coolant mass consumption, Semi-elliptic hole came out to give best results.

Vibration Analysis of Mixed Flow Pump Impeller Blade Designed Using Mean Stream Line Method

Mixed flow pumps applications have been exploited in a large number of diversified fields of engineering. They find applications as an important component in waste water treatment systems, power stations, irrigation systems etc. User requirements make these pumps to work very close to the functioning requirements and therefore under these conditions the vibrations are bound to occur in different moving components of the pump. It would be difficult to analyse the pump vibrations, considering the pump as a single system. Analysing vibrations in different moving components of the pump will not only be easier but also will aid in reducing the vibrations at the microscopic level. As a subject of the present paper, the mixed flow pump impeller blade has been designed using sparingly used yet accurate mean stream line theory. Modal analysis of the pump blade has been carried out at different modes of frequency. Total deformation for different modes of frequencies has also been determined. Stainless steel has been used as the construction material of the impeller blade.