Bernoulli’s Principle is named after the scientist “Daniel Bernoulli’s”. Who stated that if the speed of fluid (liquid or gas) increases then the pressures in the fluid decrease.
This phenomenon of Bernoulli’s Principle happens because the total energy of the moving fluid remains constant throughout the flow and to maintain this constant value of energy throughout the flow, the fluid adjusts accordingly. If the value of one of the energy increases (here speed of the fluid) then the value of other energy decreases (pressures of the fluid) to maintain the constant value of overall energy.
But the ‘Bernoulli’s Equation’ was not given by ‘Daniel Bernoulli’s ‘. He just stated the relationship between fluid speed and its pressure. The ‘Bernoulli’s Equation’ was given by another scientist called ‘Leonhard Euler’ in the year 1752.
Assumptions While Applying Bernoulli’s Equation:
- It is assumed that the flow is steady.
- It is also assumed that flowing fluid is incompressible. Which means its density remains constant throughout.
- The friction produced due to the viscosity of the fluid is neglected.
Bernoulli’s Equation –
P + 1/2 ρ v2 + ρgh = Constant
Where,
P = Pressure head
ρgh = Potential head
1/2 ρ v2 = Kinetic head
This equation gives a relation between fluid pressure, kinetic energy, and gravitational potential energy.
Total Head (H) = Pressure head + Kinetic head + potential head
P = Pressure exerted by a fluid at a given point
ρ = Density of the fluid throughout
V = Velocity of the fluid at a given point
g = Acceleration due to gravity
h = Height or elevation at which fluid is flowing from a reference point.
So, from Bernoulli’s Equation, we can say that the fluid pressure, kinetic energy, and gravitational potential energy remains constant throughout during the motion of the fluid, or in other words, we can say that the total Mechanical energy of the moving fluid in a streamline which includes pressure, kinetic, potential energy remains constant at all the points in that particular streamline.
Bernoulli’s Equation follows ” Laws of conservation of energy “.