Abstract:
The study of improved heat transfer performance is
referred to as heat transfer enhancement,
augmentation, or intensification. In general, this
means an increase in heat transfer coefficient.
Energy- and materials-saving considerations, as well
as economic incentives, have led to efforts to produce
more efficient heat exchange equipment. Common
thermal-hydraulic goals are to reduce the size of a
heat exchanger required for a specified heat duty, to
upgrade the capacity of an existing heat exchanger, to
reduce the approach temperature difference for the
process streams, or to reduce the pumping power. The
study of improved heat transfer performance is
referred to as heat transfer enhancement,
augmentation, or intensification. In general, this
means an increase in heat transfer coefficient. [1]
General techniques for enhancing heat transfer can be
divided in three categories. One is passive method
such as twisted tapes, helical screw tape inserts,
rough surfaces, extended surfaces, additives for
liquid and gases. The second is active method, which
requires extra external power, for example
mechanical aids, surface fluid vibration, use of
electrostatic fields. Passive methods are found more
inexpensive as compared to other group.
