Questions about fluids
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The essence of Bernoulli’s equation is the conservation of mechanical energy in a fluid. That is: kinetic energy + gravitational potential energy + pressure potential energy = constant. The formula for this is https://bkimg.cdn.bcebos.com/pic/3b292df5e0fe992543bed75d3ba85edf8db17109. Here, one-half multiplied by density multiplied by the square of velocity represents kinetic energy; the expression for kinetic energy is Ek = (mv^2)/2. In Bernoulli’s equation, the mass associated with kinetic energy is replaced by density – why is that?
Density is equal to mass divided by volume; the Bernoulli equation should be an equation in which all terms are divided by volume. It seems to be something like that、、
The kinetic energy per unit mass of fluid is u^2/(2), the kinetic energy per unit weight of fluid is u^2/(2g), and the kinetic energy per unit volume of fluid is ρu^2/2.
Right, are fluids divided into equal volumes and equal masses?
If you do the calculations to the end, you will find that pressure has nothing to do with mass and is related to density instead
The Bernoulli equation is expressed per unit mass of fluid… To convert energy from J/kg to pressure in Pa units, isn’t it necessary to multiply by the density?