NEW METHOD TO DETERMINE THE VIRTUAL MASS COEFFICIENT VIRTUALLY FOR SOLID SPHERE PASSES THROUGH NEWTONIAN AND NONNEWTONIAN LIQUIDS IN HYDROPHOBIC CASE

Abstract

A new Method is presented to calculate the virtual mass coefficient for solid sphere entering water as Newtonian liquid and Carboxy Methyl Cellulose CMC and Poly Vinyl Alcohol PVA as non-Newtonian liquids with air cavity (hydrophobic entry). The sphere's motion is recorded using high speed digital camera (1000 frame/s). The virtual mass coefficient is calculated virtually by measuring the cavity surface area part that covering the sphere' surface to the immersed part with liquid so the values of CVM varies between (0.25-0.5). In this method, the shape of square is drawn on transparent paper to put it on the monitor of the recorded video at the center of the moving sphere, the measuring square grades are calculated and designed to give the values of CVM (0.25, 0.3, 0.35, 0.4 and 0.45), CVM equals 0.5 for hydrophilic case (without cavity) when the cavity is collapsed due to liquid's drag and static liquid pressure at a certain depth that become more than air cavity pressure inside the cavity. At that instance, the sphere becomes fully immersed in liquid.