DYNAMIC FORCE EXERTED BY FLUID JET ON STATIONARY AND MOVING PLATES

Dynamic forces exerted by fluid on plate normal to jet

Dynamic Force Exerted By Fluid Jet

—Dynamic force: 

The force exerted by virtue of fluid motion is called a "Dynamic force".

Fluid Jet: 

Is a stream of fluid issuing from a nozzle with a high velocity and hence a high kinetic energy.

—Force exerted can be evaluated using  Impulse-Momentum

principle.

Dynamic force applied = Rate of change of momentum.

—F= m*dv/dt.

APPLICATION OF LINEAR MOMENTUM PRINCIPAL

INTRODUCTION

Ø Equation of motions is build on the basis of the balance of momentum principal.

Ø In particle mechanics a particle P that has mass m and move with the velocity v is said to posses (linear) momentum mv and the general statement of Newton ’s second law is

                                  d(mv)=F. (1). dt

LINEAR MOMENTUM AND IMPULSE EQUATIONS

   Linear Momentum Equation

   The linear momentum of a particle with mass ‘m’ moving with velocity ‘v’ is defined as product of mass and velocity .i.e:

      p = mv

    It is based on the law of conservation of momentum or on the momentum principle, which states that the net force acting on a fluid mass is equal to the change in momentum of flow per unit time in that direction. The force acting on a fluid mass ‘m’ is given by the Newton’s law of motion,

   F=m*a

Dynamic Force and Power

 •Forces that result when an object moves through a fluid, or when a fluid moves past an object.

•Dynamic forces arise due to the relative motion of an object in a fluid.  There must be motion.