## Abstract

Two and three dimensional simulations of an airlift reactor in a steady state at low gas flow rates are presented. The simulations are based on a two-fluid model with a k -ε model for the turbulence and as little as possible ad hoc closure terms. The results are compared with a one-dimensional mechanical energy balance and are found to be in good agreement. The 2D results show sensitivity to the gas inlet geometry: whether or not gas is partially sparged into the liquid directly next to a wall affects the liquid velocity distribution and thereby the gas disengagement at the top of the airlift. The 3-dimensional calculations make a more realistic geometry possible. The friction in the system is found to be about a factor of two larger in the 3D case at the same gas inlet conditions. For a given gas flow rate, the mean gas fraction in the riser is the same for the 2D and 3D simulations, the liquid circulation rate is about 30% higher in the 2D case than in the 3D one.

Original language | English |
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Pages (from-to) | 101-108 |

Number of pages | 8 |

Journal | American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP |

Volume | 424 |

Publication status | Published - 2000 |

Externally published | Yes |