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Force Convection

In: Science

Submitted By noormi
Words 945
Pages 4
Title: Forced Convection
Objective:
To demonstrate the use of extended surface such as fin and pin to improve the heat transfer in forced convection.
Introduction:
Convection is the study of conduction in a fluid as enhanced by its "convective transport", that is, its velocity with respect to a solid surface. It thus combines the energy equation, or first law of thermodynamics, with the continuity and momentum relations of fluid mechanics. The causes of convection are generally described as one of either natural or forced. However the distinction between natural and forced convection is particularly important for convective heat transfer.
Forced convection or also known as heat advection studies the heat transfer between a moving fluid and a solid surface. There are various types of forced convection, such as flow in a tube or across a flat plate and so on. In forced convection, the fluid has a nonzero streaming motion in the field away from the body surface, caused perhaps by a pump or fan or other driving force independent of the presence of the body. Also in this class are bodies moving through a still fluid, since fluid velocities are forced and may be large, heat transfer via forced convection will usually be significantly larger. It should be considered as one of the main methods of useful heat transfer as significant amounts of heat energy can be transported very efficiently and this mechanism is found very commonly in everyday life, including central heating, air conditioning, steam turbines and in many other machines. Convection is also used in engineering practices to provide desired temperature changes, as in heating of homes, industrial processes, cooling of equipment, etc.

Theoretical background: Convection is one of the major modes of heat transfer and mass transfer. Convective heat and mass transfer take place through individual particles...

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