Introduction to heat transfer processes, conduction and radiation. Fourier’s law of heat
conduction, thermal conductivity, thermal conductivity of solids, liquids and gases, effect
of temperature on thermal conductivity. Newton’s law of cooling, definition of overall
heat transfer coefficient. General parameters influence the value of heat transfer
coefficient.
Conduction : General 3-Dimensoinal conduction equation in Cartesian , cylindrical and
spherical coordinates; different kinds of boundary conditions; nature of differential
equations; one dimensional heat conduction with and without heat generation; electrical
analogy; heat conduction through composite walls; critical thickness of insulation.
Units: II
Heat transfer from finned surfaces; fin efficiency and effectiveness, two dimensional
steady state heat conduction using analytical and numerical methods, periodic heat
conduction.
Convection: review of Navier – Stokes and energy equation, hydrodynamic and thermal
boundary layers; laminar boundary layer equations; forced convection appropriate non
dimensional members; effect of Prandtl number; empirical relations for flow over a flat
plate and flow through pipes.
Units: III
Natural convection: Dimensional analysis, Granhoff number, boundary layers in
external flows (flow over a flat plate only), boundary layer equations and their solutions,
heat transfer correlations.
Heat transfer with change of phase: nature of vaporization phenomena; different
regimes of boiling heat transfer; correlations for saturated liquid
vaporization;condensation on flat plates; correlation of experimental results, drop wise
condensation.
Units: IV
Heat exchanger: Different types of heat exchangers, arithmetic and
logarithmic mean temperature differences, heat transfer coefficient for parallel, counter
and cross flow type heat exchanger; effectiveness of heat exchanger, N.T.U. method,
fouling factor. Constructional and manufacturing aspects of Heat Exchangers.
Units: V
Thermal Radiation: Plank distribution law, Krichoff's law; radiation
properties, diffuse radiations; Lambert's law. Radiation intensity, heat exchange between
two black bodies heat exchanger between gray bodies. Shape factor; electrical analogy;
reradiating surfaces heat transfer in presence of reradiating surfaces.