Question

a capillary tube is attached horizontally to a constant head arrangement if the radius of the cappilary tube is increased by 10percent then the rate of flow of liquid will change nearly

Answer 1

Explanation:

A constant pressure head cannot be maintained in a horizontal tube unless we consider viscosity of the fluid.

Poiseuille's equation can be stated also as ΔP=

πr

4

8μLQ

where:

Δ P is the pressure loss;

L is the length of pipe

μ is the dynamic viscosity

Q is the volumetric flow rate

r is the radius

Δ P , μ, L remain constant so Q∝ R

4

⟹Q=KR

4

R

′

=R+0.1R=1.1R

Q

′

=K(1.1R)

4

Q

Q

′

−Q

=

R

4

(1.1R)

4

−R

4

=0.4641

Percentage increase in the rate of flow of the liquid} =46.41%