附件242 Chapter2 Fundamental Hydraulie Flnid Mechanies 2.3.2 Bernoulli Equation -conservation of energy 1.Ideal equation of Bernoulli of bernoulli-Conservation of enerey 、 +a+2g +*2g% +2g-constant omulas (2-17)is the well-know Bernoulli states that ideal fluid includ Fig.2-10 The sketch of oressure energy.potential energy.and kinetic Bernoulli equation energy These three energies can be transferred etween the total energy 2.Real equation of Bernoulli In mauy hydraulic systems the energies can be lost (the total loss is described )on the other hand.the real velocity is a nonuniform distribution and set a kinetic correction factor to offset this lost and the coefcient defied by (2-18) 13A Here a=1.1 when it is tubulent flow,and a=2 when laminar flow,but usually in practice set the a=1. after introducing the energy loss and kinetic correction factor the equation(2-17) vill be change to: =+++h (2-19) pg 2g pg 28 Notes:see p27,(1)across-section ar aI and 2 should be selected along the streamline direction of fluid flow.附件 24.2 17