Heat Transfer Operations

Importance of heat transfer in Chemical Engineering operations – and a brief description of various modes of heat transfer. Conduction: Fourier's law of heat conduction; One-dimensional steady state heat conduction equation for flat plate; Hollow cylinder and sphere, Heat conduction through a series of resistances; Critical radius of insulation; Thermal conductivity measurement; Effect of temperature on thermal conductivity; Heat transfer in extended surfaces (Fins); unsteady state heat conduction; Lumped system analysis.

Concepts of heat transfer by convection; Natural and forced convection; Analogies between the transfer of momentum and heat; Reynold’s analogy; Prandtl and Coulburn analogy. Dimensional analysis; Correlations for the calculation of heat transfer coefficients; Heat transfer coefficient for laminar and turbulent flow through a pipe.

Absorptivity, Reflectivity, transmissivity, Concept of a black body and Gray body, Basic concepts of radiation from a surface: Planck’s Law, Wien’s Displacement Law, Stefan-Boltzmann Law, Kirchhoff’s Law, Radiation heat exchange between surfaces – the view factor.

Pool boiling of saturated liquid, Characteristics, nucleate pool and forced convection boiling, boiling mechanism and curve, heat transfer correlations, heat pipes. Condensation: Mechanism and types of condensation of vapour; Drop - wise and film -wise condensation; Nusselt equation for vertical and horizontal tubes; Condensation of superheated vapours.

Parallel and counter flow heat exchangers; Log mean temperature difference; Single-pass and multi-pass heat exchangers; Double pipe; Shell and tube; Plate and frame heat exchangers; Heat exchangers effectiveness; Number of transfer unit; Fouling factors; Design of heat exchangers; Evaporator: Classification and use of evaporators in process industries, the effect of boiling point rise on evaporator performance, concept of capacity, steam economy, Single effect and multiple effect evaporation - Design calculation for single and multiple effect evaporation.