Chapter 6 Transport Phenomena In Biochemical reactors Mass Transfer Criteria for simple and Complex Systems (1)
Chapter 6 Transport Phenomena In Biochemical Reactors Mass Transfer Criteria for Simple and Complex Systems (1)
参考阅读: 《生化反应动力学与反应器》 戚以政汪淑雄编著 第6章生化反应器的传递过程 第5章生化反应器的设计与分析 第7章生化反应器的流动模型与放大
参考阅读： 《生化反应动力学与反应器 》 戚以政 汪淑雄 编著 • 第6章 生化反应器的传递过程 • 第5章 生化反应器的设计与分析 •第7章 生化反应器的流动模型与放大
Chapter 5 Basic Concepts of Transport Phenomena In Bio-engineering and chemical Engineering 25 1 Transport phenomena and reaction are the basic phenomena in the nature, Chemical Engin. and Bio engin. concentration gradient, there must be momento If there is velocity gradient, temperature gradient, transfer, heat transfer and mass transfer For momentum transfer there is newton 's law of viscosity as follows xx==1
dy dvx yx = − Chapter 5 Basic Concepts of Transport Phenomena In Bio-engineering and Chemical Engineering 5.1 Transport phenomena and reaction are the basic phenomena in the nature, Chemical Engin. and Bioengin. If there is velocity gradient, temperature gradient, or concentration gradient, there must be momentum transfer, heat transfer, and mass transfer. For momentum transfer, there is Newton’s Law of Viscosity as follows:
-shear stress, u -----viscosity of the fluid. Momentum flux=-viscosity velocity gradient Fluids tha at behave in this fashion are termed newtonian fluids, Fluids that do not obey this law are referred to as non Newtonian fluids. The subject of non-Newtonian flow is a subdivision of rheology For the heat transfer. there is fourier 's law of heat Conduction as follows q q/a-The local heat flow per unit area; heat flux k-m- thermal conductivity Heat flux= thermal conductivity temperature gradient
-----shear stress, -------viscosity of the fluid. Momentum flux = - viscosity velocity gradient Fluids that behave in this fashion are termed Newtonian fluids, Fluids that do not obey this law are referred to as nonNewtonian fluids. The subject of non-Newtonian flow is a subdivision of Rheology. For the heat transfer, there is Fourier’s Law of Heat Conduction as follows: q/A -----The local heat flow per unit area; heat flux k ----- thermal conductivity. Heat flux = thermal conductivity temperature gradient dy dT k A q = −
For the mass transfer there is Fick's first law D 4 AB A the molar diffusion flux of a in a binary system D AB mass diffusivity; p mass density Molar diffusion flux=mass diffusivity* density gradient Assumption of Constant C and dab in a binary system with chemical reaction, the molar diffusion differential equation DARO 2 )+R ay az RA- the molar rate of production A
jA- -----the molar diffusion flux of A in a binary system; DAB ----- mass diffusivity; ------- mass density; Molar diffusion flux = mass diffusivity density gradient Assumption of Constant C and DAB in a binary system with chemical reaction, the molar diffusion differential equation: RA ------ the molar rate of production A dy d j D A A AB = − For the mass transfer, there is Fick’s First Law: A A A A AB A R z c y c x c D Dt Dc + + + = ( ) 2 2 2 2 2 2