GUJARAT TECHNOLOGICAL UNIVERSITY
BE -SEMESTER-VIII EXAMINATION- SUMMER 2020
--- Content provided by FirstRanker.com ---
Subject Code: 2180507 Date: 28/10/2020
Subject Name: Transport Phenomena
Time:02:30 PM TO 05:00 PM Total Marks: 70
Instructions:
- Attempt all questions.
- Make suitable assumptions wherever necessary.
- Figures to the right indicate full marks.
--- Content provided by FirstRanker.com ---
MARKS | ||
---|---|---|
Q.1 (a) State the relevance of transport phenomena in chemical Engineering. | 03 | |
(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 °C and 854 atm, given the molecular weight 28 g/g-mole, pc = 33.5 atm, and Tc = 126.2 K | 03 | |
(b) State the shell momentum balance equation and its boundary conditions. | 04 | |
(c) State and discuss the Newton’s law of viscosity along with supporting equations and schematic diagram. | 07 | |
OR | ||
(c) Glycerin at 26.5 °C is flowing through a horizontal tube 1 ft long and with 0.1 inch inside diameter. For a pressure drop of 40 psi, the volume flow rate (w/p)-is 0.00398 ft3/min. The density of glycerin at 26.5 °C is 1.261 g/cm3. Find the viscosity of the glycerin and subsequent-Reynolds no. | 07 | |
Q.3 (a) Give the physical significance of the three kinds of time derivatives used in the equation of change for momentum transport. | 03 | |
(b) Discuss the general trends of viscosity with temperature and pressure for-ordinary fluids. | 04 | |
(c) Write a-brief note on molecular theory of the viscosity of gases at low density. | 07 | |
OR | ||
Q.3 (a) A plastic panel of area 1 ft2 and thickness 0.252 inch was found to conduct heat at a rate of 3 W at steady state with temperature T1 = 24 °C and T2 = 26 °C imposed on the two main surfaces. What is the thermal conductivity of the plastic in cal/cm.s.K at 25 °C. | 03 | |
(b) State the boundary conditions associated with shell energy balance. | 04 | |
(c) State and discuss various kinds of Navier-Stokes equation initiated from molecular arguments. | 07 | |
Q.4 (a) Discuss the significance of momentum, thermal and mass diffusivities | 03 | |
(b) A copper wire has a radius of 2 mm and a length of 5 m. For what voltage drop what the temperature rise at the wire axis be 10 °C, if the surface temperature of wire is 20 °C? | 04 | |
(c) Explain with appropriate equations the Fourier’s law of molecular energy transport | 07 | |
OR | ||
Q.4 (a) Write in short about Molecular Mass Transport. | 03 | |
(b) Show that only one diffusivity is needed to describe the diffusional behavior of a binary mixture. | 04 | |
(c) Derive the equation for temperature and heat flux distribution through cylindrical shell with an electric heat source. | 07 | |
Q.5 (a) Define thermal conductivity and thermal diffusivity. What are its units? | 03 | |
(b) Using the equation of combination of kinetic theory and 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 | 04 | |
Species | Tc (k) | Pc (atm) |
CO | 133 | 345 |
CO2 | 304.2 | 72.9 |
The values for constants are a=2.745 x 10-4 & b=1.823 | ||
(c) Derive the relation for diffusion with a heterogeneous chemical reaction with suitable assumptions and notations. | 07 | |
OR | ||
Q.5 (a) Compare convective and molecular molar fluxes. | 03 | |
(b) State the various-equations of diffusivities for temperature and pressure dependence. | 04 | |
(c) Deduce the expression for diffusion through a stagnant gas film with appropriate schematic diagram. | 07 |
--- Content provided by FirstRanker.com ---
This download link is referred from the post: GTU BE 2020 Summer Question Papers || Gujarat Technological University