Analisis aliran didalam Cyclone Separator dengan Simulasi CFD menggunakan CFDSOF

Analisis aliran didalam Cyclone Separator dengan Simulasi CFD menggunakan CFDSOF Abstrak

1. Pengantar

Agus Nuryadi

The first systematic design based on the residence time theory for all groups of cyclones and hydrocyclones were proposed by Massarani (1997). In this principle, if the time it stays inside the cyclone is equal to or longer than the time required to hit the wall, a particle of a given size will be captured. The cut's size corresponds to the particle size that, if entered precisely at the center of the inlet pipe, enters the wall during the residence period (t) (Svarovsky, 1984). Massarani equation-related diameter of cut size (d50); parameter (K) Depending on the shape of the cyclone; the physical properties of the system; and the volumetric feed flow rate (Q), as revealed in the equation below.

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Where g(cv) introduces the effect of concentration on the cut size diameter, g (cv) is approximately equal to one for studies with a heavily diluted suspension. Furthermore, The nomographs by Zanker can be used to make a preliminary estimate of the size of cyclone needed. The specialist manufacturers of hydrocyclone equipment should be consulted to determine the best arrangements and design for a particular application. Zanker’s method is outlined below and illustrated in the Example below and based on an empirical equation by Bradley (1960):

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Where, d50 is the particle diameter for which the cyclone is 50 per cent efficient, Dc is diameter of the cyclone chamber, u is liquid viscosity, L is feed flow rate, pl = density of the liquid, and ps = density of the solid. The Euler number is the other significant parameter in the cyclone analysis (Eu). The pressure drop in the cyclone ( ∆ P) with the kinetic energy per unit volume of feeding refers to this dimensionless amount. Also, The greater the number of Euler values, the greater the equipment's cost of energy. By equation, the Euler number is defined.

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where uc is the average velocity of the fluid in the cylindrical section of the cyclone. Parameter K and the Euler number (Eu) for the Lapple cyclone, as well as the range of gas velocity in the feed section (u), according to Massarani. The ratio between the mass of particles accumulated in the underflow and the mass of particles fed into the cyclone determined the overall efficiency of the separation (η).

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Individual separation efficiency (η) is a parameter related to the equipment's separation efficiency for just one particle size. This variable is determined based on knowledge of the overall separation efficiency (η (head)) and the particles' grade distribution in the underflow and feeding, as shown in the following equation. An individual efficiency of separation of 50%, the cut size diameter.

The Eulerian-Lagrangian method and the multiphase particle in cell (MPPIC) method have been used in this study. The model of the MPPIC is a Model Collision in CFDSOF. First of all, PIC models are derived from a Liouville equation describing the time evolution of a particle distribution function.

5. Hasil dan Pembahasan

5.1 Verifikasi 5.2 Validasi 5.3 Pembahasan

   5.3.1 ....

   5.3.4. Parcel Fluida

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