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CE 230-Engineering Fluid Mechanics. Lecture # 25-27 ENERGY EQUATION. Bernoulli Equation did not account for 1) Energy loss due to viscous resistance 2) Energy that can be add to the system through a device 3) Energy that can be taken from the system through a device
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CE 230-Engineering Fluid Mechanics Lecture # 25-27 ENERGY EQUATION
Bernoulli Equation did not account for 1) Energy loss due to viscous resistance 2) Energy that can be add to the system through a device 3) Energy that can be taken from the system through a device These are some of the limitations of BE Instead we will use an equation that takes care of all these This is the Energy Equation for1-D, steady, incompressible flow: = 1 for uniform v Close to 1 turbulant Close to 2 laminar
Find K.E. correction factor for flow in a circular pipe if the velocity is given by: Recall
Example 7.3 Compare your results with results obtained using BE)
Concept of EGL & HGL The total head (energy/unit weight) can be split into three components: 1) Elevation head 2) Pressure head 3) Velocity head To see the variation of the flow energy we may draw a line called EGL