question_answer

According to fan laws, which of the following relation is valid? (Q \[-\] discharge, N \[-\] speed, D \[-\] diameter) Subscripts 1 and 2 for two sets of conditions):

A) \[\left( \frac{{{Q}_{1}}}{{{Q}_{2}}} \right)={{\left( \frac{{{N}_{1}}}{{{N}_{2}}} \right)}^{2}}\]        

B) \[\left( \frac{{{Q}_{1}}}{{{Q}_{2}}} \right)={{\left( \frac{{{N}_{1}}}{{{N}_{2}}} \right)}^{3}}\]

C) \[\left( \frac{{{Q}_{1}}}{{{Q}_{2}}} \right)={{\left( \frac{{{D}_{1}}}{{{D}_{2}}} \right)}^{2}}\]        

D) \[\left( \frac{{{Q}_{1}}}{{{Q}_{2}}} \right)={{\left( \frac{{{D}_{1}}}{{{D}_{2}}} \right)}^{3}}\]