Thermo Lab Experiment 1
I. Objective
The first objective of the measurement of thermal conductivity & one-dimensional heat conduction experiment was to identify three different metal specimens by comparing their experimentally determined thermal conductivities to known thermal conductivity values of existing metals. The second objective of the experiment was to establish a connection between the thermal conductivities & temperatures of the metal specimens. Thirdly, the contact resistance of the interfaces between the specimens was to be determined.
II. Theory
Particles of a substance always interact with each other. There’s a transfer of energy with each of there interactions. The energy is transferred from the higher excited particles to the lesser excited particles, which this energy transfer is called conduction. Fourier’s Law governs conduction, which deems that the heat transferred through a substance is proportional to the change in temperature over the substances thickness. The ability to transfer heat through conduction is dependent on the substances thermal conductivity, which is denoted as k. The property k is dependent on the substances atomic structure & temperature, which will be verified in this experiment. The governing law of conduction, known as Fourier’s Law of Heat Conduction is represented by the equation: [4]
Qcond= -kAcdTdx
(1)
Qcond represents the rate of heat conduction; Ac represents the cross-sectional area that the heat is being transferred through; k represents the thermal conductivity of the material; dTdx represents the approximation for temperature gradient across the thickness of the substance.
Ac, which represents the cross-sectional area that the heat is being transferred through, can be calculated by using the following equation: [4]
Ac= π4D2
(2)
D represents the diameter of the specimen.
Conduction through solids occurs in all three directions, but in this experiment the heat is assumed to only conduct axially.
The first objective of the measurement of thermal conductivity & one-dimensional heat conduction experiment was to identify three different metal specimens by comparing their experimentally determined thermal conductivities to known thermal conductivity values of existing metals. The second objective of the experiment was to establish a connection between the thermal conductivities & temperatures of the metal specimens. Thirdly, the contact resistance of the interfaces between the specimens was to be determined.
II. Theory
Particles of a substance always interact with each other. There’s a transfer of energy with each of there interactions. The energy is transferred from the higher excited particles to the lesser excited particles, which this energy transfer is called conduction. Fourier’s Law governs conduction, which deems that the heat transferred through a substance is proportional to the change in temperature over the substances thickness. The ability to transfer heat through conduction is dependent on the substances thermal conductivity, which is denoted as k. The property k is dependent on the substances atomic structure & temperature, which will be verified in this experiment. The governing law of conduction, known as Fourier’s Law of Heat Conduction is represented by the equation: [4]
Qcond= -kAcdTdx
(1)
Qcond represents the rate of heat conduction; Ac represents the cross-sectional area that the heat is being transferred through; k represents the thermal conductivity of the material; dTdx represents the approximation for temperature gradient across the thickness of the substance.
Ac, which represents the cross-sectional area that the heat is being transferred through, can be calculated by using the following equation: [4]
Ac= π4D2
(2)
D represents the diameter of the specimen.
Conduction through solids occurs in all three directions, but in this experiment the heat is assumed to only conduct axially.