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What is Fluid Kinematics?

  Fluid mechanics one branch is fluid kinematics . It deals with the study of velocity and acceleration of the particles of fluids in motion and their distribution in space without considering any force or energy involved.   The motion of fluid can be described fully by an expression describing the location of a fluid particle in space at different time’s thus enabling determination of the magnitude and direction of velocity and acceleration in the flow field at any instant of time. Methods of Fluid Motion: There have two methods for fluid motion. a.       Eulerian method: In this method, the observer concentrates on a point in the fluid system. Velocity acceleration and other characteristics of the fluid at that particular point are studied. Eulerian method is exclusive method in flid mechanics because of it’s mathematical simplicity. b.       Langrangian method: In this method the observer concentrates on the movement of a single particle. The path taken

What is basic difference between a Turbine and The Pump?

Centrifugal Pump    A centrifugal pump is a contrivance which provides energy to a fluid in a fluid system. It assist to increase the pressure energy or kinetic energy or both of the fluid by converting the mechanical energy.   What is basic difference   between   a Turbine and The Pump?   The basic difference between a turbine and   the pump, from hydrodynamic point of views. Is that in the former flow takes place from the high pressure side to low pressure side. Whereas in pump flow take place from the low pressure towards the high pressure. Thus in a   turbine there is accelerated flow,   while the pump the flow is decelerated.   Why transformer is rated in KVA?                                                                             How and Why an increase in secondary or load current causes an increase in primary current?                                                What is the difference between dynamo breaking a

Why transformer is rated in KVA?

If a 60 Hz transformer is operated in 50 Hz, but at rated voltage, will it be hotter or cooler at full load?   We know , If a transformer rated in KW, it will be meaning less. Because   will change according to load. So transformer is rated in KVA. As seen, Cu loss of a transformer depends on current and   iron loss on voltage. Hence total transformer loss depends on volt-amp (VA) and not on phase angle between voltage and current i.e. it is independent of load power factor. That is why rating transformer is in KVA not in KW.             If rated voltage is applied but a frequency other than rated is used in a transformer, it is seen from equation, , that the flux must change inversely with the frequency change in order to maintain the same induced voltage. The core loss varies almost directly as the square of the flux and only directly with the frequency. A decrease in the supply Frequency will therefore require an increase in flux and consequently