Chemical engineering calculations to assist process, plant operation and maintenance engineers.

CHECALC

`Scale-up Ratio, R = (V2/V1)`^{1/3}

Shaft speed scaling is done based on following relation:

`N2 = N1 . (1/R)`^{n}

The value of n, called the scaling exponent, depends on the physical result to be scaled.

Units | Base Case | Scale up | ||
---|---|---|---|---|

Volume | V | m^{3} |
400 | 300 |

Vessel Diameter | T | mm | 400 | 300 |

Liquid Level | Z | mm | 400 | 300 |

Agitator Diameter | D | mm | 400 | 300 |

Equivalent Diameter | Teq = (4.V/π)^{1/3} |
mm | 400 | 300 |

Scaling Exponent | n | 2 | ||

Shaft Speed | N | rpm | 400 | 300 |

Reynold's No. | Re = D^{2}.N.ρ/μ |
|||

Tip Speed | π.D.N | m/s | ||

Flow Number | Nq | |||

Pumping Rate | Q = Nq.N.D^{3} |
m^{3}/s |
400 | 300 |

Power Number | Np | |||

Power Drawn | P = Np.ρ.N^{3}.D^{5} |
kW | 400 | 300 |

Power/ Volume | P/V | kW / m^{3} |
400 | 300 |

Froude Number | Fr = N^{2}.D/g |
|||

Bulk Velocity | Vc = 4.Q/(π.Teq^{2}) |
m/s | 400 | 300 |

Scale of Agitation | 400 | 300 |