Home /
Expert Answers /
Mechanical Engineering /
a-method-for-determining-the-thermal-conductivity-k-and-the-specific-heat-c-p-of-a-material-is-ill-pa865
(Solved): A method for determining the thermal conductivity k and the specific heat c_(p) of a material is ill ...
A method for determining the thermal conductivity k and the specific heat c_(p) of a material is illustrated in the sketch. Initially the
two identical samples of diameter D=45mm and thickness L=11mm and the thin heater are at a uniform temperature of
T_(i)=23\deg C, while surrounded by an insulating powder. Suddenly the heater is energized to provide a uniform heat flux q_(0)^(?)^('') on
each of the sample interfaces, and the heat flux is maintained constant for a period of time, \Delta t_(0). A short time after sudden heating
is initiated, the temperature at this interface T_(0) is related to the heat flux as
T_(0)(t)-T_(i)=2q_(0)^(?)^('')((t)/(\pi \rho c_(p)k))^((1)/(2))
For a particular test run, the electrical heater dissipates 15 W for a period of \Delta t_(0)=100s, and the temperature at the interface is
T_(0)(t=55s)=36\deg C after 55 seconds of heating. A long time after the heater is deenergized, t?\Delta t_(0), the samples reach the
uniform temperature of T_(0)(t->\infty )=50\deg C. The mass of each sample is m=66g.
Determine the specific heat and thermal conductivity of the test material.