# Download GTU B.Tech 2020 Summer 8th Sem 2180507 Transport Phenomena Question Paper

Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 8th Sem 2180507 Transport Phenomena Previous Question Paper

Seat No.: ________
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE ?SEMESTER-VIII EXAMINATION- SUMMER 2020

Subject Code: 2180507

Date: 28/10/2020
Subject Name: Transport Phenomena
Time: 02:30 PM TO 05:00 PM

Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.

MARKS
Q.1 (a) State the relevance of transport phenomena in chemical
03
Engineering.

(b) State and explain the laws of Conservation.
04

(c) State and discuss various levels of transport phenomena.
07

Q.2 (a) Estimate the viscosity of N2 at 50 OC and 854 atm, given the
03
molecular weight 28 g/g-mole, pc = 33.5 atm, and Tc = 126.2 K

(b) State the shell momentum balance equation and its boundary
04
conditions.

(c) State and discuss the Newton's law of viscosity along with
07
supporting equations and schematic diagram.

OR

(c) Glycerin at 26.5 OC is flowing through a horizontal tube 1 ft long
07
and with 0.1 inch inside diameter. For a pressure drop of 40 psi,
the volume flow rate (w/) is 0.00398 ft3/min. The density of
glycerin at 26.5 OC is 1.261 g/cm3. Find the viscosity of the
glycerin and subsequent Reynolds no.
Q.3 (a) Give the physical significance of the three kinds of time derivatives
03
used in the equation of change for momentum transport.

(b) Discuss the general trends of viscosity with temperature and
04
pressure for ordinary fluids.

(c) Write a brief note on molecular theory of the viscosity of gases at
07
low density.

OR

Q.3 (a) A plastic panel of area 1 ft2 and thickness 0.252 inch was found
03
to conduct heat at a rate of 3 W at steady state with temperature
T1 = 24 OC and T2 = 26 OC imposed on the two main surfaces.
What is the thermal conductivity of the plastic in cal/cm.s.K at 25
OC.

(b) State the boundary conditions associated with shell energy
04
balance.

(c) State and discuss various kinds of Navier-Stokes equation initiated
07
from molecular arguments.

1

Q.4 (a) Discuss the significance of momentum, thermal and mass 03
diffusivities

(b) A copper wire has a radius of 2 mm and a length of 5 m. For what
04
voltage drop what the temperature rise at the wire axis be 10 OC, if
the surface temperature of wire is 20 OC?

(c) Explain with appropriate equations the Fourier's law of
07
molecular energy transport

OR

Q.4 (a) Write in short about Molecular Mass Transport.
03

(b) Show that only one diffusivity is needed to describe the
04
diffusional behavior of a binary mixture.

(c) Derive the equation for temperature and heat flux distribution
07
through cylindrical shell with an electric heat source.
Q.5 (a) Define thermal conductivity and thermal diffusivity. What are its
03
units?

(b) Using the equation of combination of kinetic theory and
04
corresponding states arguments estimate DAB for the system of
CO-CO2 at 296.1 K and 1 atm total pressure. The data is given as
follows
Species
Tc (k)
Pc (atm)
CO
133
34.5
CO2
304.2
72.9
The values for constants are a = 2.745 ? 10-4 & b = 1.823

(c) Derive the relation for diffusion with a heterogeneous chemical
07
reaction with suitable assumptions and notations.

OR
Q.5 (a) Compare convective and molecular molar fluxes.
03
(b) State the various equations of diffusivities for temperature and
04
pressure dependence.
(c) Deduce the expression for diffusion through a stagnant gas film
07
with appropriate schematic diagram.
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