Answered step by step
Verified Expert Solution
Link Copied!

Question

1 Approved Answer

Calculate the mass transfer coefficient and molar flux for flow of a fluid over a flat plate. Part A . Pure water at 5 0

Calculate the mass transfer coefficient and molar flux for flow of a fluid over a flat plate.
Part A. Pure water at 50C is flowing parallel over a flat plate of solid benzoic acid that is 0.25m long at a velocity of 0.0667ms. The benzoic acid is dissolving and diffusing into the water at steady-state. The density of water at 50C is 988.07kgm3, the viscosity is 5.4910-4Pa*s, and the solubility of benzoic acid in water is 0.07kg-molm3. The diffusivity of benzoic acid in water at 25C is 1.21x10-9m2s and the viscosity of water at 25C is 8.9410-4Pa.s. Calculate the mass transfer coefficient kC and the molar flux of benzoic acid (NA)
Part B. Pure dry air at 70C is flowing parallel over a volume of liquid water with a length 0.25m with a velocity of 1.333ms. The water, which completely wets the surface that is blotting paper, is diffusing into the air at steady state. The density of air at 70C is 1.0376kgm3, the viscosity is 2.04910-5Pa*s, and the vapor pressure of water is 0.3075atm. The diffusivity of water vapor in air at 25C is 2.6010-5m2s. The total pressure of the system can be assumed to be constant at 1atm. Calculate the mass transfer coefficient kG and the molar flux of water (NA).
Part C.
A sphere of naphthalene 2 inch in diameter is placed in air at 115F flowing with a velocity of 1.1ftsec. The vapor pressure of solid naphthalene is 0.565mmHg and the diffusivity of naphthalene in air and at 115F is 7.510-5ft2sec. Determine the mass transfer coefficient ((:kGG} in lbmol/((:ft2-hr-atm} and the mass transfer flux of naphthalene to air (NA) and the total mass evaporated (WA) in Ibmol/hr in this stagnant air at 115F and 1atm.
Data:
Properties of air at1atm and 115F are:
Density ()=0.0692lbft3
Viscosity ()=0.0469lbft-hr
R=0.73(atm)-ft3lbmol-R,KG=kcRT
NA=KG(PA1-PA2)
image text in transcribed

Step by Step Solution

There are 3 Steps involved in it

Step: 1

blur-text-image

Get Instant Access with AI-Powered Solutions

See step-by-step solutions with expert insights and AI powered tools for academic success

Step: 2

blur-text-image

Step: 3

blur-text-image

Ace Your Homework with AI

Get the answers you need in no time with our AI-driven, step-by-step assistance

Get Started

Students also viewed these Chemical Engineering questions