다중규모 모사 Multiscale simulation for process development [Example 1: FBR for polysilicon]

다중규모 모사

Multiscale simulation for process development

[Example 1: FBR for polysilicon]

Major: Interdisciplinary program of the integrated biotechnology

Graduate school of bio- & information technology Youngil Lim (N110), Lab. FACS

Youngil Lim (N110), Lab. FACS phone: +82 31 670 5207 (direct) phone: +82 31 670 5207 (direct)

Fax: +82 31 670 5445, mobile phone: +82 10 7665 5207 Fax: +82 31 670 5445, mobile phone: +82 10 7665 5207 Email:

Email: [email protected]@hknu.ac.kr, homepage:, homepage:   http://facs.maru.nethttp://facs.maru.net

+ multi-component: SiH

, H

, Si(g), Si(s) + multi-phase: gas and solid

+ multi-physics: hydrodynamics (velocity, temperature, and concentration), reaction (decomposition), crystallization

(nucleation, agglomeration, breakage, growth), gravity, Heat and mass transfer + multi-scale (time):

- silane decomposition: ~µs - gas and particle mixing: ~s

- wall and reactor heat transfer: ~min - crystal growth: ~hr

+ multi-scale (length):

- micro-scale: particle nucleation, growth, agglomeration and breakage (PBE).

- macro-scale: fluid dynamics (CFD) - process-level: overall mass balance,

particle size control and fluidized particle mass control.

Example 1. Polysilicon production by FBR: characteristics

Process-level objectives

+ To obtain polysilicon particles with uniform and big size.

+ To maximize the recovery within 9N purity + To control the fluidized particle mass at a set

point adjusting W.

+ To control the particle size uniformly adjusting S, F

, T, and solid holdup (

).

Example 1. Polysilicon production by FBR: objectives

Multi-scale simulation

+ Process-level modeling: overall mass balance.

+ Fluid-level modeling: CFD (computational fluid dynamics).

+ Particle size dynamics: PBE (population balance equation).

+ Reaction: CVD (chemical vapor deposition)

kinetics

Solution strategy

+ Sequential approach: sequential solving of CFD/CVD/PBE modules.

+ Simultaneous approach: simultaneous solving of the three modules

Example 1. Polysilicon production by FBR: multi-scale simulation

Solution tools

+ Process-level modeling: Matlab

+ Fluid-level modeling: Fluent for CFD

+ Particle size dynamics: Matlab for PBE

+ Reaction: Matlab for CVD

Momentum balance for gas and solid phases

Example 1. Polysilicon production by FBR: CFD modeling

Mass balance

Energy balance for gas and solid phases

Number-based PBE

Example 1. Polysilicon production by FBR: PBE modeling

Nucleation:

Growth:

Agglomeration or

Breakage:

Particle inlet/outlet: q

and q

CVD reaction kinetics

Example 1. Polysilicon production by FBR: CVD modeling/mass

Overall mass balance and P-control

Example 1. Polysilicon production by FBR: model analysis 1

powder

sc

c

k Y  

out , i in , i

j i j

j i i j , i

j k

k j k , j i

i i

i i i

i i

i i i

i

i

q q

m m c m c k c

c A k

Y A m m

m A

Y A m

m m A

Y A dt

dM  

 



 

 

 



  

W Y

dt S

dM   

Example 1. Polysilicon production by FBR: model analysis 2

• Design parameters

• Operating conditions:

• Thermodynamic/physical properties

• Model parameters

• Computational parameters

• Independent and dependent variables

• Initial condition (IC) and boundary condition (BC)

Example 1. Polysilicon production by FBR: model analysis 3

Accumulation term

Convection term:

Diffusion term (more extendedly tensor term)

Source term (reaction, gravity, etc.)

Signs in Navier-Stokes equation

Units of each terms

Summary of Example 1

- Multi-scale simulation approach

- Advantages