Chemical Engineering - Mechanical Operations - Discussion

Discussion Forum : Mechanical Operations - Section 2 (Q.No. 33)
33.
The power number for a stirred tank becomes constant at high Reynolds number. In this limit, the variation of power input with impeller rotational speed (N) is proportional to
N°
N1
N2
N3
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
9 comments Page 1 of 1.

Veere said:   1 month ago
N2 is for laminar.

Mudit Tripathi said:   5 months ago
In the limit of high Reynolds numbers, the variation of power input with impeller rotational speed (N) is proportional to N^3.

Desai said:   3 years ago
N^3 is the correct Answer.

Dewa said:   5 years ago
Np=constant at high Reynolds number.

Hence, P N^3.

Arindom said:   7 years ago
The answer should be n3.

Prakash Dhanaraj said:   7 years ago
At Nre<10 (laminar) it is N^2.
At Nre>10000 (turbulent) it is N^3.
(1)

Ankit said:   8 years ago
Yes, agree @Sangram.

Sangram said:   9 years ago
@Nagaraj.

No, at high Reynolds number power does not depend on the Reynolds number and its proportional to n^3.

Nagaraj said:   1 decade ago
power number = power/n^2 *d^3 *viscosity.

This at high Reynolds number so p is directly proportional to n^2.
(1)

Post your comments here:

Your comments will be displayed after verification.