Upload
others
View
10
Download
1
Embed Size (px)
Citation preview
Measuring Thermal Conductivity using a Student-built Apparatus and Modulated Differential Scanning
Calorimeter
Shera Demchak Research Advisors Dr. Bill Heffner & Dr. Ray Pearson
WHAT IS HEAT FLOW? Heat flow is the transfer of heat
energy from a warmer region to a colder region
Modes of Heat Transfer: Convection, Radiation, Conduction
Differential Scanning Calorimetry is a method for measuring Thermal Conductivity as recommended by American Society for Testing and Materials (ASTM)
PRICES $$$
Q2000 TA Instruments DSC
Student-Built Apparatus
~ $ 115,000 (retail) ~ $ 65,000 (ed. discount)
________?
PRICES $$$
Q2000 TA Instruments DSC
Student-Built Apparatus
~ $ 115,000 (retail) ~ $ 65,000 (ed. discount)
< $ 100
The Student-Made Apparatus
1
2
3
4 5 6
7
8
9
10 11
12
13
VOLTAGE DATA
First Peak: Aluminum
Second Peak: PMMA
0.00
100.00
200.00
300.00
400.00
500.00
600.00
0
100
200
300
400
500
600
700
800
900
0.00 20.00 40.00 60.00 80.00 100.00
delta
T
delta
Q
time (min)
RAW DATA
dQ dT
Conceptually: Conductors have a HIGH dQ and LOW dT,. Insulators have a LOW dQ and HIGH dT.
*dQ and dT are in digital units.
THE STUDENT-BUILT APPARATUS
dQ = k * (A/L) * ΔT
ΔT = change in temperature (K) (A/L) = area of sample / length (m) k = Thermal Conductivity Constant (W / K m) dQ = Heat Flow (W)
-0.2
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0 0.2 0.4 0.6 0.8 1 1.2
Expe
rim
enta
l K v
alue
s
Literature K Values
Student-Built Compared to Literature
Student-built Apparatus
Polymethyl Methacrylate
Teflon
Pyrex
High-density Polyethylene
Foam
MODULATED DIFFERENTIAL SCANNING CALORIMETER (MDSC)
REFERENCE DISC
SAMPLE DISC
THERMOCOUPLE
EXPERIMENTAL THERMAL CONDUCTIVITY
k
k
HOW THE DIFFERENTIAL CALORIMETER SCANNER WORKS
-0.2
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0 0.2 0.4 0.6 0.8 1 1.2
Expe
rim
enta
l K v
alue
s
Literature K Values
Comparing the Student-Built Apparatus with the DSC
DSC
Student-built Apparatus
Polymethyl Methacrylate
Teflon
Pyrex
High-density Polyethylene
Foam
The student-built apparatus is cheaper, simpler, and faster!
Acknowledgments I would like to thank the following people for training me,
mentoring me, bandaging me, and offering me their advise during my hours in the lab.
Dr. Heffner and Dr. Pearson Lauren Bacigalupo Maria Salamon Marisa Sanders Amelia Labak Steve Antalics
Further Reading: ASTM Standard E1952, 2011, "Thermal Conductivity and Thermal Diffusivity by Modulated Temperature Differential Scanning Calorimetry," ASTM International, West Conshohocken, PA, 2011, wwwastm.org. Hatakeyama, T. and F. X. Quinn"Thermal Analysis: Fundamentals and Applications to Polymer Science." 2nd Edition. John Wiley & Sons. 1999.
Thank you to the International Materials
Institute for its support!