lecture07

# lecture07 - LECTURE 7 THERMODYNAMICS An Engineering...

This preview shows pages 1–4. Sign up to view the full content.

1 LECTURE 7 THERMODYNAMICS An Engineering Approach NONREACTING IDEAL GAS MIXTURES & PSYCHROMETRICS Dr. MinJun Kim Department of Mechanical Engineering & Mechanics Drexel University Describing Mixture Composition To specify the state of a mixture requires the composition and the values of two independent intensive properties such as temperature and pressure. i i i M m n ! Mass Number of moles: Molecular weight Mass fractions: m m mf i i ! " ! ! j i i mf 1 1 Mole fractions: n n y i i ! " ! ! # # # # ! j i i j n n n n n n 1 3 2 1 ... " ! ! j i i y 1 1 Molecular weight of the mixture: i j i i M y M " ! ! 1 n m M !

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2 Approximate Composition of Dry Air Component Mole Fraction (%) Nitrogen Oxygen Argon Carbon dioxide Neon, helium, methane, and others 78.08 20.95 0.93 0.03 0.01 kmol kg M / 97 . 28 ) 01 . 44 ( 0003 . 0 ) 94 . 39 ( 0093 . 0 ) 00 . 32 ( 2095 . 0 ) 02 . 28 ( 7808 . 0 ! # # # \$ p-V-T Relationships for Ideal Gas Mixtures Dalton Model: premises that each mixture component behaves as an ideal gas as if it were alone at the temperature T and volume V of the mixture . V T R n p ! V T R n p i i ! i i i i y n n V T R n V T R n p p ! ! ! / / Amagat Model: is that each mixture component behaves as an ideal gas as if it existed separately at the pressure p and temperature T of the mixture . p T R n V i i ! i i i i y n n p T R n p T R n V V ! ! ! / /
3 U, H, & S for Ideal Gas Mixtures " ! ! # # # # ! j i i j U U U U U U 1 3 2 1 ... " ! ! # # # # ! j i i j H H H H H H 1 3 2 1 ... " ! ! # # # # ! j i i i j j u n u n u n u n u n u n 1 3 3 2 2 1 1 ... " ! ! # # # # ! j i i i j j h n h n h n h n h n h n 1 3 3 2 2 1 1 ... " ! ! j i i i u y u 1 " ! ! j i i i h y h 1 " ! ! j i i v i v c y c 1 " ! ! j i i p i p c y c 1 " ! ! j i i s y s 1 Ms s Mc c Mc c Mh h Mu u v v p p ! ! ! ! ! , , , , i i i i v i i v i p i i p i i i i i i s M s c M c c M c h M h u M u ! ! ! ! ! , , , , For mixture, For component i , Mixture Processes @ Constant Composition %& " ! ! j i i i i T u T u n U U 1 1 2 1 2 ) ( ) ( " ! ! j i i i i T h T h n H H 1 1 2 1 2 ) ( ) ( " ! ! ( j i i i i T h T h y h 1 1 2 ) ( ) ( " ! ! ( j i i i i T u T u y u 1 1 2 ) ( ) ( " !

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 02/28/2011 for the course MEM 310 taught by Professor Miller during the Winter '08 term at Drexel.

### Page1 / 10

lecture07 - LECTURE 7 THERMODYNAMICS An Engineering...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online