Boundary conditions?

Question

Can anyone explain the need of boundary conditions if passible taking reference of heat transfer

Answer 1

I'm not really sure there are lots of boundaries in heat transfer. If you do an energy balance you set a boundary and look at the heat transfer across the boundary.

In a heat exchanger you need to know the fluid properties at the boundary between the heat transfer fluid and the surface of the exchanger. Those boundary conditions are used to establish the heat transfer rate across that boundary. (Film theory)

In unsteady state heat transfer the boundary conditions might be the temperatures in questions at time equal zero and time equal infinity.

Answer 2

I think, in the context of this type of analysis, the "boundary conditions" might refer to known properties at the boundaries of the area being considered. For instance, you might have a constant temperature source or a heat sink.

Boundary conditions are often used to solve for unknown constants in a solution. By "plugging in" the known values at the boundary conditions, you can get an exact solution for the problem being analyzed

Answer 3

Boundary conditions refer in general to unlikely test cases or conditions that occur around the "edge" of the problem being analyzed. They are typically less common.

Example, if you are writing a computer program to calculate the square root of a number, typical boundary condition(s) would be (a) very large number, (b) very small number, (c) zero, (d) one, (e) a negative number.

So in your example, you need to frame the problem, and then identify applicable boundary conditions.