A bioreactor is scaled up based on equal impeller tip speed. Consider the following parameters for small and large bioreactors:

Parameters	Small bioreactor	Large bioreactor
Impeller speed	N1	N2
Diameter of impeller	D1	D2
Power consumption	P1	P2

Assuming geometrical similarity and the bioreactors are operated in turbulent regime, what will be $$\frac{{{P_2}}}{{{P_1}}}$$ ?

A. $${\left( {\frac{{{D_1}}}{{{D_2}}}} \right)^2}$$

B. $${\left( {\frac{{{D_2}}}{{{D_1}}}} \right)^2}$$

C. $${\left( {\frac{{{D_1}}}{{{D_2}}}} \right)^5}$$

D. $${\left( {\frac{{{D_2}}}{{{D_1}}}} \right)^5}$$

Answer: Option A