Tutorial Modeling of monolith reactors

More documents

Recommendations

Info

Energy and mass balances • There are two main classes <strong>of</strong> porous media models. • Heterogeneous model: – The fluid and solid temperatures and concentrations are taken to be different. The two phases are coupled using heat and mass transfer coefficients. • Pseudo-homogeneous model – The fluid and solid temperatures and concentrations are taken to be the same. This situation corresponds to infinitely large heat and mass transfer coefficients. For transient simulations the heterogeneous model is recommended. 56
Energy balances The fluid phase energy balance is: ∂T f φρ f CPf , + ρ fCPf , v i ∇ Tf = ∇ i ( keff, f∇Tf) − hav( Tf−TS) ∂ t The solid phase energy balance is: ∂ T S ( 1 −φ) ρ C = ∇i( k ∇ T ) + ha ( T − T ) + ( ΔH ) η( R ) S P, S eff, S S v f S R i i ∂ t i = 1 m ∑ The effective thermal conductivity for each phase depends on the porosity and material properties. see Hayes et al., Catalysis Today 2009 57
Page 1 and 2:
Introduction to Monolith Reactor Mo
Page 3 and 4:
Why use computer modelling? • Exp
Page 5 and 6: Observations • The problem involv
Page 7 and 8: Model Scales Micro scale: At the at
Page 9 and 10: Mathematical formulation • The fu
Page 11 and 12: Basic models in common use • Sing
Page 13 and 14: The 3D SCM • The real monolith do
Page 15 and 16: The 2D approximate SCM • The 2D m
Page 17 and 18: The 2D SCM • All of the physical/
Page 19 and 20: Modelling the fluid domain Velocity
Page 21 and 22: Modelling the washcoat domain • T
Page 23 and 24: Diffusion in the washcoat • Diffu
Page 25 and 26: Modelling the substrate domain The
Page 27 and 28: Comparing 2D and 3D models • The
Page 29 and 30: Comparing 2D and 3D models • The
Page 31 and 32: Comparing 2D and 3D models Percenta
Page 33 and 34: Review of boundary layer flow Flow
Page 35 and 36: Boundary layers in a tube • At th
Page 37 and 38: Heat and mass transfer • Heat and
Page 39 and 40: 1D SCM mass balances The fluid phas
Page 41 and 42: 1D SCM energy balances The fluid ph
Page 43 and 44: Nusselt and Sherwood numbers • Fo
Page 45 and 46: Nusselt and Sherwood numbers • Ho
Page 47 and 48: Nusselt and Sherwood numbers • Ho
Page 49 and 50: Simplified 1D models • Dispersion
Page 51 and 52: Models for the converter • In rea
Page 53 and 54: Discrete converter models • A pas
Page 55: Momentum balance equation Velocity
Page 59 and 60: Continuum model • In effect, the
Page 61 and 62: Model validation • All models mus
Page 63 and 64: Model validation - Example Heating
Page 65: Advertising supplement R.E. Hayes a
show all

Tutorial Modeling of monolith reactors

Create successful ePaper yourself

Delete template?

Save as template?