GAZI UNIVERSITY FACULTY OF ENGINEERING

DEPARTMENT OF MECHANICAL ENGINEERING

MM 309E HEAT TRANSFER

HOMEWORK II

Due on: October 12th, 2015

Q1. Fluid flows on the right surface of a composite wall, consisting of material A and B, at

heat transfer coefficient of h and temperature

of T. Left surface of the composite wall is

exposed to heat flux q

. Thermal conductivities

of material A and B are kA and kB, respectively.

LA and LB show the thicknesses of the

materials.

(a) Express the differential equations and the

boundary conditions at steady state for material A and B.

(b) Obtain a relation for the variation of temperature in material A and B by solving the

differential equation.

(c) Obtain a relation that gives the temperature at x=0.

(d) Obtain a relation that gives the temperature at x=LA.

(e) Obtain a relation that gives the temperature at x=LB.

October 3, 2015

Assoc. Prof. Dr. Ouz TURGUT