THE EQUATION OF CONTINUITY
Presented By : Vika Tresnadiana Yuke Djulianti Yuli Nurul Maulida
DEFINITION
Definition of The Equation Continuity
The equation of continuty expresses that at ideal fluid flow, the cross product of fluid flow speed with its section area is constan.
THEORY AND FORM
If a fluid flows in a steady flow through a pipe with different section areas, then the volume of fluid that passes at each section is equally large in the same time interval. PIPA BERLUAS v1
PENAMPANG BESAR (A1) DENGAN LAJU ALIRAN FLUIDA (v1)
A1
A2 v2
v1
A1
Therefore the mass of iquid passing through part 1 during time interval t is :
m1 = 1 . V1 = 1 (A1 . x1) m1 = 1. A1 (v1. t)
PIPA BERLUAS PENAMPANG KECIL (A2) DENGAN LAJU ALIRAN FLUIDA (v2)
While the mass of fluid passing through part 2 during time interval t is :
m2 = 2 . V2 = 2 (A2 . x2) m2 = 2.A2(v2.t)
Because the fluid flow is steady, then the mass of fluid entering or passing through part 1 is equal to that of coming out or passing through part 2. So that obtained the following equation :
m1 = m2 1.A1.v1.t = 2.A2.v2.t
Because the multiplication between speed of fluid flow and section area (A.v) is known as debit (Q), then the equation of continuity in ideal fluid can also be expresses as flows :
Q1 = Q2 Q1 = k
DEBIT
If a fluid flows in a pipe with section area A and the velocity of fluid v, then the amount of flluid (volume) that flows passing that section per unit of time is called debit. In the form of equation,V/t Q = debit is formulated as follow :
Where : Q = debit of fluid flow (m3/s) V = volume of fluid in motion (m3) t= time (s)
Because the volume of fluid V = section area A x length of part l Q = A l /t Because the length of part l divided by time t is the velocity of fluid flow, then the equation above can be written as follows A v Q=:
Where : A = section area (m3) v = the velocity of fluid flow (m/s)