IIChE NITR

  HYDRODYNAMIC CAVITATION     Venturi hydrodynamic cavitation   Rotational Hydrodynamic Cavitation   Hydrodynamic cavitation is a process of vaporization, bubble generation, and bubble implosion which occurs in a flowing liquid as a result of a decrease and subsequent increase in local pressure. Cavitation will only occur if the local pressure declines below the saturated vapor pressure of the liquid. The bubble generated will collapse with a subsequent recovery above the vapor pressure.   Hydrodynamic cavitation can be produced by passing a liquid through a constricted channel at a specific flow velocity or by mechanical rotation of an object through a liquid. Based on the geometry of the system, the combination of pressure and kinetic energy create the hydrodynamic cavitation cavern downstream of the local constriction generating high energy cavitation bubbles. Different cavitation types can be generated by liquid flow initial steady cavitation, developed cavitati

  All fluids can be broken down into two basic types, Newtonian, and non-Newtonian.     NEWTONIAN FLUIDS A Newtonian fluid's   viscosity constant, no matter the amount of shear applied for a constant temperature.. These fluids have a linear relationship between shear stress & shear rate.. Examples: · Water · Mineral oil · Gasoline · Alcohol   NON-NEWTONIAN FLUIDS You can probably guess that non-Newtonian fluids are the opposite of Newtonian fluids. When shear is applied to non-Newtonian fluids, the viscosity of the fluid changes. The behavior of the fluid can be described in following ways: Time Independent:- · Dilatant - Apparent v iscosity of the fluid increases when shear is applied. (Apparent viscosity= Slope of Shear stress & shear rate curve)   For example: · Quicksand · Cornflour and water · Silly putty · Pseudoplastic - Pseudoplastic is the opposite of dilatant; the more shear applied, the less viscous it becomes. For example: