Chemical Engineering - Fluid Mechanics - Discussion
Discussion Forum : Fluid Mechanics - Section 1 (Q.No. 26)
26.
A particle A of diameter 10 microns settles in an oil of specific gravity 0.9 and viscosity 10 poise under Stoke's law. A particle B with diameter 20 microns settling in the same oil will have a settling velocity
Discussion:
22 comments Page 1 of 3.
May Saadoon said:
1 year ago
u(A)/u(B) = [dp(A)/dp(B)]^2.
u(A)/u(B) = [ 10 / 20 ] ^2.
u(A)/u(B) = 1/4,
u(A) = 1/4 u(B).
u(A)/u(B) = [ 10 / 20 ] ^2.
u(A)/u(B) = 1/4,
u(A) = 1/4 u(B).
(2)
TANMAY SHAH said:
2 years ago
The settling velocity, and, as a result, settling time, are proportional to the diameter of the spherical particle squared.
The larger the sphere diameter, the faster the particle will settle.
The smaller the particle diameter, the longer it will stay suspended in the fluid.
So, V2/V1 = (D2)^2/(D1)^2.
V2/V1 = 20^2/10^2,
V2 = 4 V1.
So, option-D is the right answer.
The larger the sphere diameter, the faster the particle will settle.
The smaller the particle diameter, the longer it will stay suspended in the fluid.
So, V2/V1 = (D2)^2/(D1)^2.
V2/V1 = 20^2/10^2,
V2 = 4 V1.
So, option-D is the right answer.
(13)
Abhay kumar Pandey said:
3 years ago
Settling velocity is directly proportional to the diameter of the particle (having an increasing trend).
DAN said:
3 years ago
Anyone, please explain the right answer.
Yash said:
3 years ago
Yes, D is correct, in the stokes region, settling velocity varies (D)^ (2).
Solving gives Vb= 4* Va.
Solving gives Vb= 4* Va.
Dharmendra Kumar tadav said:
3 years ago
The Correct answer is D.
Vicky said:
3 years ago
Vt proportional d^2.
So, option D is right.
So, option D is right.
Bashir said:
5 years ago
D is the right option.
Zeeshanulhaq said:
6 years ago
At low Reynolds number settling velocity is proportional to square of dp, then d is answer. While for very low or very high Reynolds velocity is proportional to underroot dp.
Mangesh said:
7 years ago
@Manoj.
Diameter = 2* radius.
Not; Radius = 2* diameter.
Diameter = 2* radius.
Not; Radius = 2* diameter.
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