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Lecture - 7 ( jet strikes on moving curved plates )

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Let's continue after lecture 6 Jet strikes at the tip of moving vane ​ We are using all our same previous notations, the only difference is that in this case curved plate is there and jet is striking at the tip of this moving curved vane. V1 is the velocity of water jet with respect to ground entering at the tip of moving curved vane making angle α with horizontal axis. Water jet enter vane at entry point 1 and get deflected by δ angle and exit as velocity V2 m/sec making angle 'β' with horizontal axis. This curved vane is moving with velocity 'U' as shown in below figure.  Now first of all let me draw a parallel vector U1 on entry and U2 at exit. After that as we know V1 is the water Jet velocity entering on vane with respect to ground and vane is moving with velocity U1, so the relative velocity of water Vr1 (velocity with respect to blade) will never enter the vane with angle α. Entering angle of both the velocity vector V1 and Vr1 is not same, so they

Lecture - 6 ( jet strikes on inclined flat moving plate )

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Jet strikes on inclined flat moving plate Let us consider an plate which is free to move linearly and inclind at at an angle θ. The jet of water is striking at the centre of the plate horizontally. Mass flow rate of water Jet is denoted by 'm' in Kilogram per second. As we know the plate is moving with velocity U with respect to ground and velocity of water Jet at entry of plate is V1 with respect to ground. m1 is the mass flow rate exiting from the above end of the plate and m2 is the mass flow rate exiting from the below end of the plate. Point2 denote both the the above and below exit point of jet on the plate. Point1 is the entry point of jet on the centre of plate. U1' represent velocity of entry point of plate and 'U2' represent velocity of exit point of plate. When Jet strikes the plate, it will move in linear direction so here U = U1 = U2. Now in this case also concepts of relative velocity will be used. V1 represents velocity of jet at entry with res

Lecture - 5 ( jet strikes on flat moving plate)

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Let's continue after lecture4 Jet strikes with moving flat plate  let us consider a plate which is free to move linearly with velocity 'U'. Point 1 represent the entry point of Jet on plate. Point 2 represent exit point of jet on Above and below ends of the plate. 'U1' represent velocity of entry point of plate and 'U2' represent velocity of exit point of plate. When Jet strikes the plate, it will move in linear direction so here U = U1 = U2. Now in these cases concepts of relative velocity will be used. V1 represents velocity of jet at entry with respect to ground. Remember one thing that any relative term which is represented with respect to ground are absolute term. So here V1 is also called as absolute velocity of jet. Similarly U is also called as absolute velocity of plate because U is velocity of plate with respect to ground. V2 represents velocity of Jet at exit with respect to ground and it is also called as absolute velocity of Jet at exit

Lecture - 4 ( Impact of jet on stationary curved plates )

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Let's continue after lecture 3 Jet strikes at the centre of stationary symmetric curved plate Let us consider a stationary flat plate on the centre of which water Jet striking perpendicularly, denote this centre point of plate as point 1, which is entry point of water jet. After striking the plate water will split equally in two parts. Let's consider waterjet is coming out of nozzle with mass flow rate 'm' and with velocity 'V1'. After splitting into equal parts, water will exit from top and bottom ends of the plate. Denote both of these end points of plate with point 2, which is exit point of water jet. The mass flow rate exiting from top end of plate is 'm/2' and with exit velocity V2. Similarly the mass flow rate exiting from bottom end of plate is 'm/2' and with exit velocity V2. As water is traveling over the curved plate there is no change of pressure on the entry and exit point of plate so P1 = P2 = P atm . At exit point 2, wat

Prandtl-number

Prandtl number (Pr) Prandtl number signifies that, how much heat is carried away by how much fluid, transferring from one point to another. Mathematically it is defined as the ratio of momentum diffusivity to the thermal diffusivity. It is dimensionless quantity. Let's understand little bit about diffusivity. Conduction is basically the ability to transfer the things from one place to other place. It signifies how much material or medium is supporting in transferring things. Just opposite to this property conduction we have one more property called diffusion. It's basically a storage capacity or we can say absorbing ability of material. For particular material diffusivity is defined as, how much conducting property is dominating over storage property. So from here we can conclude that net transfer is not represented by conduction it represented by diffusion. Kinematic viscosity shows net transfer of molecular movement that's why it's called momentum dif

Lecture - 3 (jet strikes stationary vertical and inclined flat plate)

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Jet strikes on vertical stationary flat plate Let us consider a stationary vertical plate on which a jet is striking. The jet is having diameter 'd'. The mass flow rate of Jet is represented by 'm' kg/s. This simply means that 'm' kilogram of water is coming out of nozzle per second. The jet is striking at the middle of the plate with velocity 'V1' metre per second. After the impact of Jet on the plate, the jet will split equally and flows over the plate. After that the jet will exit the plate from its tip in tangential direction. Now here Jet is striking the plate normally or perpendicularly at point 1 and exit the plate tangentially from the tip of the vertical plate represented by point 2 with velocity 'V2' m/s. If we consider this plate to be frictionless then the entry velocity and exit velocity will be same (V1=V2). Also the pressure throughout the plate is atmospheric, wheather it will be on entry point of plate which is point 1 or it

Lecture - 2 (impact of jets)

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Before starting with impact of jets we must learn about forces. Force is nothing but rate of change in linear momentum. When we apply force on a body, than its Momentum will change and this change in momentum will represented by subtraction of initial momentum of body from its final momentum. Force applied on a body = final momentum of body - initial momentum of body Let us consider a stationary vertical plate on which a jet is striking. The jet is having diameter 'd'. The mass flow rate of Jet is represented by 'm' kg/s. This simply means that 'm' kilogram of water is coming out of nozzle per second. The jet is striking at the middle of the plate with velocity 'V1' metre per second. After the impact of Jet on the plate, the jet will split equally and flows over the plate. After that the jet will exit the plate from its tip in tangential direction. Now here Jet is striking the plate normally or perpendicularly at point 1 and exit the plate tangential