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The analysis performed was on the transient heat transfer on similarly shaped samples of different materials to determine the thermal conductivity for an unknown material. The four samples included two slabs and two spheres. One of each shape was made of Aluminum with known material properties, and one of each shape was made of an unknown material. To determine the thermal conductivity, the samples, which were initially at room temperature, were submerged into a temperature controlled water bath. The internal temperature change with respect to time of each sample was measured by a thermocouple placed within the sample. LogUD software was utilized to extract the transient temperature readings. The change in the temperature gradient with respect to time was used to curve fit the data. This data was then used to compare the experimental values of θ* with the calculated values of θ*0. The value of k then adjusted to have a close match for the data curves, and determining the material’s identity based on k value chosen. This is a cheap way to calculate the k value of an unknown material. The unknown slab was found to be Polycarbonate with k = 0.155 Btu/hr-ft2-F with an error of 41%. The unknown sphere was found to be PVC with k = 0.009 Btu/hr-ft2-F with an error of 85%.

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  • University of Arkansas Mechanical engineering department

    MEEG 4202L Lab III: February 24, 2014

    Thursday Section Group 3

    Pump Performance Measurement Stacy Evans, Josh Parker, Nuwan Liyanage, Ford Lewallen

    [email protected], [email protected], [email protected], [email protected]

    ABSTRACT

    The analysis performed was on the transient heat transfer on similarly shaped samples of different materials to determine the thermal conductivity for an unknown material. The four samples included two slabs and two spheres. One of each shape was made of Aluminum with known material properties, and one of each shape was made of an unknown material. To determine the thermal conductivity, the samples, which were initially at room temperature, were submerged into a temperature controlled water bath. The internal temperature change with respect to time of each sample was measured by a thermocouple placed within the sample. LogUD software was utilized to extract the transient temperature readings. The change in the temperature gradient with respect to time was used to curve fit the data. This data was then used to compare

    the experimental values of * with the calculated values of *0. The value of k then adjusted to have a close match for the data curves, and determining the materials identity based on k value chosen. This is a cheap way to calculate the k value of an unknown material. The unknown slab was found to be Polycarbonate with k = 0.155 Btu/hr-ft2-F with an error of 41%. The unknown sphere was found to be PVC with k = 0.009 Btu/hr-ft2-F with an error of 85%.

    NOMENCLATURE T Temperature oF Ti Initial Temperature oF T Infinite Temperature oF Bi Biot Number unit-less h Heat Transfer Coefficient Btu/hr-ft2-F k Thermal Conductivity Btu/hr-ft-F As Surface Area ft2

    V Volume ft2

    cp Specific Heat Btu/lbm-F Density lbm/ft3

    tc Time Constant s L Thickness ft Thermal Diffusivity ft2/s Fo Fourier Number unit-less r0 Radius ft

    0 Temperature Gradient unit-less

    C Correlation Coefficient unit-less Position Within Body unit-less

    INTRODCUTION

    The concept of heat transfer as a result of a temperature difference between two objects is widely known throughout the science and engineering community; likewise, it is dominantly applied when analyzing heat transfer within a system.

    Furthermore, comparing the different means of heat transfer, including heat transfer by conduction and convection, allows one to experimentally determine the material of an unknown sample. The thermal conductivity of a sample is determined by the material that the sample is composed of. The convection heat transfer coefficient, however, is determined by the geometry of the sample. If the convection heat transfer coefficient is known for a sample that is geometrically similar to a sample of an unknown material, the convection heat transfer coefficient will be constant; therefore, a mathematical solution can be applied to determine the thermal conductivity of the unknown material and thus the material itself. The ratio of the internal resistance of a body to heat conduction to its external resistance to heat convection is known as the Biot number. When the Biot number is less than 0.1, the object is approximated to have a uniform temperature distribution throughout the body and can be evaluated using lumped system analysis. As the Biot number increases, a temperature gradient begins to from within the object. If high accuracy is not relevant, lumped system analysis can still be used; however, one-term approximation results in more accurate results when the Biot number is outside of this criterion. If the heat transfer coefficient is high enough, the Biot number infinitely increases. From this, a third method of determining material properties is derived. Thus, the heat transfer properties of a material can be mathematically determined for a range of temperature differences as a function of time and location.

    OBJECTIVE

    The objective of this lab is to determine the thermal

    conductivity and heat transfer coefficient for a slab and sphere

    of both known and unknown materials by analyzing their

    temperature changes over time when exposed to a constant

    temperature environment.

    THEORY When an object with a uniform initial temperature (Ti) is

    placed within a medium with a uniform temperature (Tinf), heat will be transferred from the object with a higher temperature to the other object at an logarithmic rate until both are in thermal equilibrium. As the temperature of both objects reach equilibrium, the rate of heat transfer will exponentially decrease. This is shown in Figure 1 below.

  • 2 Copyright 2013 by UARK MEEG

    Figure 1: Temperature profiles of a wall when Tinf < Ti [2]

    Using a thermocouple to measure the temperature change with respect to time of a sample placed in an environment at Tinf, a range of data points of temperature (T), and time (t) can be recorded. A ratio of these temperature values, known as the dimensionless temperature value, can be determined as shown in Equation 1.

    inf

    inf*

    TT

    TT

    i

    (Eq. 1)

    The heat transferred during this experiment can be calculated using Equation 2.

    TmCdtTThA pis )( inf (Eq. 2)

    Integrating Equation 2 provides the following solutions

    p

    s

    VC

    hAb

    (Eq. 3)

    bt

    i

    AeTT

    TT

    inf

    inf* (Eq. 4)

    Where, A is a based on the Biot number. The thermal conductivity of a sample is the resistance of the material to conduct heat. This value can be experimentally determined using three different mathematical solutions. The Biot number determines the best approach and is calculated using Equation 5,

    k

    hLB ci (Eq. 5)

    Where, Lc is the volume divided by the surface area. If the Biot number is less than 0.1, the system can be treated as a lumped mass. Lumped System Analysis assumes a uniform temperature distribution throughout the body. Using this method, the heat transfer coefficient of a sample with a known material composition can be determined at any given time using Equation 6.

    VC

    thA

    TT

    TT

    p

    s

    i exp

    inf

    inf* (Eq. 6)

    Once the heat transfer coefficient is known, the thermal conductivity of a sample with the same geometry but different material composition can be determined using one-term approximation for both slab and spherical geometries. Taking the experimental values found and solving Equation 1 results in a range of * that can be plotted verses time on a data analysis program such as Microsoft Excel. Once plotted, an exponential trend line can be added with the corresponding function in the form of A*exp(-bt) as shown in Equation 4. Equation 7 relates the one-term approximation of * with information found using lump system analysis

    Fo

    eC2

    1

    1

    * (Eq. 7)

    Where, Fo is the Fourier number, C1 is a function of , and is a function of the Biot number. These values are computed using Equations 8 through 11

    2L

    tFo

    (Eq. 8)

    pC

    k

    (Eq. 9)

    Slab: )2sin(2

    )sin(4

    11

    11

    C (Eq. 10a)

    Sphere: )2sin(2

    )]cos()[sin(4

    11

    1111

    C (Eq. 10b)

    Bi

    aa

    Bi

    aa 32

    102

    1

    exp1

    (Eq. 11)

    Where, a0, a1, a2, and a3 are constants that are dependent on the geometry of the sample. Comparing Equation 7 and Equation 4, it can be concluded that C1=A, where A was graphically determined. Substituting A for C1 in Equation 10 yields one equation with one unknown

    value, . Therefore, can be calculated. Next, Equation 1 and Equation 7 can be equated so that the only unknown value is the Fourier Number. Once the Fourier number is determined, can then be calculated by rearranging Equation 8. Finally, Equation 9 can be rearranged to solve for the thermal conductivity. An alternative method to using lumped system analysis to determine the heat transfer coefficient and thus the thermal conductivity is to assume that the heat transfer coefficient is infinity large. This causes the Biot number to become infinite, reducing Equation 11 as shown below.

  • 3 Copyright 2013 by UARK MEEG

    202

    1

    1aa

    (Eq. 12)

    From Equation 12, can be calculated, and the same process as discussed can be followed.

    EXPERIMENTAL SETUP

    This experiment was performed in the Mechanical Engineering building at the University of Arkansas Fayetteville in the first lab experiment hub down the hall of room 109. The setup for the experiment is shown in Image 1 of App A. Fill the bath with water and heat with the heater/circulator. Attach the thermocouple to the LJTick-InAmp, the LJTick-InAmp to the LabJack, and the LabJack to the computer and open LabView software. Measure the time it

    takes for the four sample specimens to reach by attaching the thermocouple to them and placing them (individually) in the circulation chamber of the bath.

    PROCEDURE

    1. Turn on pump/heater. 2. Turn thermostat to desired temperature and allow bath

    to reach steady state.

    3. Attach LJTick-InAmp to FI04, FI05 channels. 4. Connect k-type thermocouple to the corresponding

    positive and negative screw terminals.

    5. Connect the 10k resistor to the negative screw terminal and to the ground screw terminal.

    6. Make sure all LJTick-InAmp switches are off. 7. Set the gain to 201 by turning switch 10 on. Set the

    voltage offset to +0.4V by turning switch 5 on. See

    Appendix B

    8. Open the LogUD software. 9. Convert the voltage difference in the thermocouple to

    oC by inputting the scaling equation

    y=TCVoltsToTemp[thermocouple

    type:tcVolts:cjTemp]-273.15 into the first scaling

    equation where = is entered. 10. Enter k for thermocouple type. 11. Enter (b offsetVoltage)/gain for tcVolts. Refer to

    step 7.

    12. To calibrate the thermocouple, adjust the cold junction temperature value (cjTemp) to equal the room

    temperature measured with a thermometer by adding

    or subtracting a few degrees.

    13. Set the Resolution to 1, the interval to .5s, and the number of channels to 2.

    14. Put the metal slab into the tub and click write to file to begin recording temperature. Record until

    -ln(T-T)/(Ti-T) > 4.

    15. Put the plastic slab into the tub. Begin recording temperature at the time when Fo = 0.2.

    16. Repeat Step 15 for the metal sphere and the plastic sphere, recording data once Fo = 0.2.

    Note: Attach thermocouple to sample specimens before putting them in the bath.

    = [:( 0.4)

    201: 295.37 2] 273.15

    (Eq. 13)

    ln (

    ) > 4

    (Eq. 14)

    EQUIPMENT

    2 type-k thermocouples o Omega Stamford CT

    2 Resistors 10k

    Heater/Circulator o Cole Parmer o Model No. 1252-00 circulator o Type: 1252-0012, 115V, 60Hz

    Engineering Laboratory Design Inc. o Model No. 204 o Box 276

    LabJack o Model U3-HV version 1.3 o SN: 320050659

    LJTick-InAmp o Rev. 2.0

    Metal Slab Sample Specimen o 4in. x 6in. x0.5in.

    Metal Sphere Sample Specimen o 2.5in. diameter

    Plastic Slab Sample Specimen o 4in. x 6in. x0.5in.

    Plastic Sphere Sample Specimen o 2.5in. diameter

    DATA AND RESULTS

    The dimensions of each sample were measured using a dial caliper. The dimensions for the slab are shown in Table 1. All other dimensions can be found in Appendix F.

    Table 1: Slab Sample Dimensions.

    Slab Sample Units

    Height-H 0.5 ft

    Width - W 0.333 ft

    Thickness - 2L .042 ft

    Volume 0.000198749 ft^3

    Surface Area-As 0.037673675 ft^2

    T-initial 69.44 F

    T-inf 118.49 F

    Max-T 116.82 F

    The material properties of the Aluminum samples are shown in Table 2. PVC and Polycarbonate properties can be found in Appendix F.

  • 4 Copyright 2013 by UARK MEEG

    Table 2: Material Properties

    Aluminum 2024T351

    Density - 172 lbm/ft^3

    Thermal Conductivity -k 70 Btu/hr-ft-F

    Specific Heat - Cp 0.214 Btu/lbm-F

    Alpha - 1.902

    The temperature of the bath was measured by an analog thermometer. This value was entered in the LogUD to calibrate and match thermocouple temperature to bath temperature. Then the temperatures of the ambient bath and test specimen were recorded in LogUD using the initial software formula settings as explained in experimental setup. A snapshot of the experimental setup in LogUD is shown below.

    Figure 3: Log UD Screenshot

    A correction factor is considered to offset the lack of calibration in the internal temperature thermocouple. This was accounted for in LogUD program to provide accurate temperature readings. To find the heat transfer coefficient for the Aluminum slab, the temperature vs. time was plotted to ensure that an accurate logarithmic curve was generated as shown below.

    Figure 4: Temperature Curve for Aluminum Slab

    A line equation was found for the plot of * vs. Time for both the slab and the sphere samples in the form of A*EXP(-bt) using an exponential curve fit as shown in the Figures below.

    Figure 6: Theta vs. Time for Aluminum Slab

    The values A and b were used to calculate h for the aluminum samples. The h value was found to be 93.24 Btu/hr-ft2-F. Theoretically, the convection coefficient, h, should be the same for geometrically similar samples. The k value for each sample was evaluated using both one-term approximation method, and the method assuming an infinite heat transfer coefficient. This done by initially assuming k and comparing

    the experimental values of * with the calculated values of *0. To get the approximation k was adjusted to get the experimental and calculated lines matching as close as possible. Figure 7 and 8 show these curve fits.

    Figure 7: Theta vs. Time for PVC Slab

    0.00

    50.00

    100.00

    150.00

    0.0 20.0 40.0 60.0 80.0

    Temperature verses Time

    Al Slab

    y = 0.94268e-0.04083x

    R = 0.99050

    0.000

    0.200

    0.400

    0.600

    0.800

    1.000

    0.0 20.0 40.0 60.0 80.0

    * verses Time

    y = 1.4774e-0.009x

    R = 1

    0.00

    0.20

    0.40

    0.60

    0.80

    1.00

    0 100 200 300 400 500 600

    * verses Time, PVC

    *, PVC *

  • 5 Copyright 2013 by UARK MEEG

    Figure 8: Theta vs. Time for PC Slab

    Tables 4 and 5 show the calculated k values for both unknown samples. The error for k values were also recorded in the table below. Sample calculations can be found in appendix C.

    Table 4: Thermal Conductivity of Slab Samples

    Slab h k Error

    Btu/hr-ft2-F Btu/hr-ft-F %

    PVC 0.0259 0.125 116%

    Infinite 0.100 72%

    PC 0.0259 0.155 41%

    Infinite 0.012 9%

    Table 5: Thermal Conductivity of Sphere Samples

    Sphere h k Error

    Btu/hr-ft2-F Btu/hr-ft-F %

    PVC 0.0302 0.009 85%

    Infinite 0.0085 85%

    PC 0.0302 0.011 90%

    Infinite 0.010 91%

    DISCUSSION

    Initially all the samples were supposed to be at room

    temperature. After the samples were placed in the bath, a

    transfer in heat from the water occurred. Each sample had

    different rates of heating but overall the Aluminum samples

    heated much faster than the plastic samples. Also it should be

    noted that the slabs heated faster than the spheres. This showed

    that the Thermal Conductivity of Aluminum was much higher

    than the Plastic. These observations are confirmed by looking

    at the Biot number of each material and shape. Higher Biot

    numbers directly correlated to longer heating times.

    In order to calculate the thermal conductivity, the data

    needed to be plotted and curve fit. The curve fit used was an

    exponential which provided the proper form to use the one term

    approximation calculations. Thermal conductivity values were

    found for both sets of material properties. The slab was found

    to be polycarbonate; it had a lower percentage of error than the

    value found for PVC. The sphere was found to be PVC, but its

    error percentage was very close to that of PC.

    The slab was found to have a much lower percentage of error

    than the sphere. The plastic sphere was not properly sealed

    around the thermocouple and could possibly be a source of

    error. Also, the sphere had significant cracking inside the seal

    and could have added complexity to the setup. When assuming

    the Bi number was infinite, the slab had a higher percentage of

    error. Coincidentally the error for the sphere stayed roughly the

    same and still pointed to PVC. This was most likely directly

    related to the geometry and the characteristic length.

    A large portion of blame for the error in this report may be

    due the data recording or experimental setups. The heat transfer

    coefficient was found using lump mass, but when initially used

    for the unknown material calculations errors immediately

    happened. Other sources of error identified in the experiment

    included small thermocouple calibration issues, inaccuracies in

    the heating methods of the thermal bath, data fluctuations

    attributed to thermocouple movement, and inconsistent

    material properties of the test specimens.

    CONCLUSION

    Our slab was determined to be made of

    Polycarbonate with an error percentage of 41%.

    Our sphere was determined to be made of

    Polyvinylchloride with an error percentage of 85%.

    Samples with high thermal conductivities can be used

    to find convection coefficients via observing changes

    in a temperature gradient with time.

    The lower the Biot number the faster a sample can be

    heated, with respect to geometry

    Lumped analysis is valid to use for objects with a Bi

    < 0.1.

    Thermal conductivity can be approximated for

    objects with a high Bi number without knowing the

    overall heat transfer coefficient by approximating

    that the Bi ~ with limited success, mainly due to

    geometry.

    The maximum error was found when assuming Bi ~

    for the slab when assuming the material was PVC,

    with an error percentage of 116%.

    The minimum error was found when assuming Bi ~

    for the slab when assuming the material was PC,

    with an error percentage of 9%.

    ACKNOWLEDMENTS

    The members of this team would like to thank Monty Roberts and Jason Bailey for their instruction and guidance, and the

    y = 1.5273e-0.009x

    R = 1

    0.00

    0.20

    0.40

    0.60

    0.80

    1.00

    0 100 200 300 400 500 600

    * verses Time, PVC

    *, PC *

  • 6 Copyright 2013 by UARK MEEG

    University of Arkansas Mechanical Engineering Department for supplying the necessary equipment.

    REFERENCES [1] Audon Electronics, LabJack U3-LV USB Multifunction Data Acquisition Unit 2.4V Input Range, http://www.audon.co.uk/usb_multi/u3.html, Feb. 14.

    [2] Cengel, Yunus, and Afshin, Ghajar. Heat and Mass Transfer, Fundamentals & Applications. New York: McGraw-Hill, 2007. Print

    [3] LabJack, Appendix C Thermocouples, http://labjack.com/support/ljtickinamp/datasheet/appendix-c, Feb. 2014.

    [4] LabJack, LJTick-InAmp Data Sheet, http://labjack.com/support/ljtick-inamp/datasheet, Feb. 2014.

    [5] Sensors, 5-in-1 Digital Multimeter from Omega Engineering,http://www.sensorsmag.com/product/5-1-digital-multimeter-omega-engineering, Feb. 2014.

  • 7 Copyright 2013 by UARK MEEG

    APPENDIX A

    Experimental Equipment and Setup

    Image A1: Bath with heater/circulator next to thermocouple, LabJack, and LJTick-InAmp

    Image A2: View of circulation chamber, bath filled with water

    Image A3: LJTick-InAmp Image A4: Side view of heater/circulator

    Image A5: Heater/circulator Image A6: LabJack U3-HV

    Image A7: Model No. of bath and table of physical properties of material specimens Image A8: Type-k thermocouple

  • 8 Copyright 2013 by UARK MEEG

    Image A9: Metal and plastic slabs Image A10: Metal and plastic spheres

    Image A11: Example image of LabView software

  • 9 Copyright 2013 by UARK MEEG

    APPENDIX B

    LJTick-InAmp Data Sheet

    Switch

    # Name Description

    1 BxR32 Custom gain determined

    by R32

    Applies to channel B only. All off equals a gain of 1.

    2 Bx11 Gain of 11

    3 Bx52 Gain of 51

    4 Bx201 Gain of 201

    5 0.4V Output offset of +0.4

    volts.

    Voffset applies to both channels. Switch # 5 or 6 should

    always be on, but not both.

    6 1.25V Output offset of +1.25

    volts.

    7 AxR17 Custom gain determined

    by R17

    Applies to channel A only. All off equals a gain of 1.

    8 Ax11 Gain of 11

  • 10 Copyright 2013 by UARK MEEG

    9 Ax51 Gain of 51

    10 Ax201 Gain of 201

    APPENDIX C Sample Calculations

    Sample Calculation for *

    =

    =

    67.96 118.49

    69.44 118.49= 1.030

    Sample Calculation for h, given the b value found by curve * vs time.

    =

    =

    0.0408 172 0.214 0.00694

    0.403= 0.0259

    Sample Calculation for for slab

    =

    =

    0.155

    74.90 0.201= 1.91 06

    Sample Calculation for Bi of a slab

    =

    =

    0.0259 0.017

    0.155= 10.376

    Sample Calculation for 1/2 for Slab. 1

    2= 0 +

    1

    + 2

    3 = .3552 +

    . 9935

    10.376+ .0504

    3.55010.376 = 0.4708

    Sample Calculation for C1

    1 =4 sin 1

    21 + sin 21=

    4 sin 1.4574

    2 1.4574 + sin 2 1.4574= 1.4774

    Sample error calculation of error calculation for k

    = |

    | 100 = |

    0.155 0.11

    0.11| 100 = 41%

  • 11 Copyright 2013 by UARK MEEG

    APPENDIX D

    Graphs

    Figure D1: Temperature vs. Time for Aluminum Sphere

    y = -0.0044x2 + 1.0013x + 58.183R = 0.9846

    0.00

    20.00

    40.00

    60.00

    80.00

    100.00

    120.00

    140.00

    0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 160.0

    Temperature verses Time

    Al Sphere

  • 12 Copyright 2013 by UARK MEEG

    Figure D1: Theta vs. Time for Aluminum Sphere

    Figure D1: Theta vs. Time for PVC Sphere

    y = 1.3214e-0.0236x

    R = 0.9892

    0.000

    0.100

    0.200

    0.300

    0.400

    0.500

    0.600

    0.700

    0.800

    0.900

    1.000

    0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 160.0

    * verses Time

    y = 0.5024e-0.001x

    R = 1

    0.00

    0.10

    0.20

    0.30

    0.40

    0.50

    0.60

    0.70

    0.80

    0.90

    1.00

    0 200 400 600 800 1000 1200 1400 1600 1800

    * verses Time, PVC

    *, PVC *

  • 13 Copyright 2013 by UARK MEEG

    Figure D4: Theta vs. Time For PC Sphere

    Figure D5: Theta vs. Time for PVC Slab, h~infinity

    y = 0.4978e-0.001x

    R = 1

    0.00

    0.10

    0.20

    0.30

    0.40

    0.50

    0.60

    0.70

    0.80

    0.90

    1.00

    0 200 400 600 800 1000 1200 1400 1600 1800

    * verses Time, PVC

    *, PC *

    y = 1.2742e-0.009x

    R = 1

    0.00

    0.10

    0.20

    0.30

    0.40

    0.50

    0.60

    0.70

    0.80

    0.90

    1.00

    0 100 200 300 400 500 600

    * verses Time, PVC

    *, PVC *

  • 14 Copyright 2013 by UARK MEEG

    Figure D6: Theta vs. Time For PC Slab, h~infinity

    Figure D7: Theta vs. Time for PVC Sphere, h~infinity

    y = 1.2742e-0.008x

    R = 1

    0.00

    0.10

    0.20

    0.30

    0.40

    0.50

    0.60

    0.70

    0.80

    0.90

    1.00

    0 100 200 300 400 500 600

    * verses Time, PVC

    *, PC *

    y = 0.4989e-0.001x

    R = 1

    0.00

    0.10

    0.20

    0.30

    0.40

    0.50

    0.60

    0.70

    0.80

    0.90

    1.00

    0 200 400 600 800 1000 1200 1400 1600 1800

    * verses Time, PVC

    *, PVC *

  • 15 Copyright 2013 by UARK MEEG

    Figure D8: Theta vs. Time For PC Sphere, h~infinity

    Appendix E

    Observation Notes

    Ford Lewallen Experimental Setup, Procedure, Equipment, Nomenclature, References, Appendices A & B

    Stacy Evans Abstract, Introduction, Objective, Theory, Formatting and Editing

    Josh Parker Data and Analysis, Discussion, Conclusions

    Nuwan Liyanage Appendix C, Data and Results

    y = 0.4938e-0.001x

    R = 1

    0.00

    0.10

    0.20

    0.30

    0.40

    0.50

    0.60

    0.70

    0.80

    0.90

    1.00

    0 200 400 600 800 1000 1200 1400 1600 1800

    * verses Time, PVC

    *, PC *

  • 16 Copyright 2013 by UARK MEEG

    APPENDIX F

    Material Properties and Raw Data

    Table F1: Material Properties

    Material Density-lbm/ft3

    Thermal Conductivity-Btu/hr-ft-F

    Specifc Heat-Btu/lbm-F

    Aluminum 2024T351 172 70 0.214

    PVC 91.8 0.058 0.201

    Polycarbonate 74.8 0.11 0.301

    Table F2: Sample Dimensions

    L, plate 0.021 ft r0, sphere 0.104 ft

    W, plate 0.333 ft As, sphere 0.136 ft^2

    H, plate 0.500 ft V, sphere 0.005 ft^3

    As, plate 0.403 ft^2 Lc, sphere 0.035 ft

    V, plate 0.007 ft^3 , Al 172 lbm/ft^3

  • 17 Copyright 2013 by UARK MEEG

    Lc, plate 0.017 ft k, Al 70 Btu/hr-ft-F

    , Al 172 lbm/ft^3 c, Al 0.214 Btu/lbm-F

    k, Al 70 Btu/hr-ft-F , PVC 91.8 lbm/ft^3

    c, Al 0.214 Btu/lbm-F k, PVC 0.058 Btu/hr-ft-F

    , PVC 91.8 lbm/ft^3 c, PVC 0.201 Btu/lbm-F

    k, PVC 0.058 Btu/hr-ft-F , PC 74.9 lbm/ft^3

    c, PVC 0.201 Btu/lbm-F k, PC 0.11 Btu/hr-ft-F

    , PC 74.9 lbm/ft^3 c, PC 0.301 Btu/lbm-F

    k, PC 0.11 Btu/hr-ft-F

    c, PC 0.301 Btu/lbm-F

    APPENDIX G

    RAW DATA

    Sample Slab values

    t, s Ti * -ln(*) , PVC 91.80 lbm/ft^3 , PC 74.90 lbm/ft^3

    0.0 67.96 1.030 -0.030 k, PVC 0.058 Btu/hr-ft-F k, PC 0.110 Btu/hr-ft-F

    0.5 69.43 1.000 0.000 c, PVC 0.201 Btu/lbm-F c, PC 0.301 Btu/lbm-F

    1.0 70.64 0.976 0.025 , PVC 1.88E-06 , PC 1.91E-06

    1.5 71.71 0.954 0.047 Bi, PVC 12.866 Bi, PC 10.376

    2.0 73.58 0.916 0.088 1/1^2 0.4708 1/1^2 0.4869

    2.5 74.38 0.899 0.106 1 1.4574 1 1.4331

    3.0 75.59 0.875 0.134 C1 1.4774 C1 1.5273

    3.5 76.66 0.853 0.159 k, PVC 0.125 Btu/hr-ft-F k, PC 0.155 Btu/hr-ft-F

    4.0 78.12 0.823 0.195 %ER, PVC 116% %ER, PC 41%

    4.5 79.19 0.801 0.222

    5.0 80.12 0.782 0.246

    5.5 81.32 0.758 0.277

  • 18 Copyright 2013 by UARK MEEG

    6.0 82.79 0.728 0.318

    Sample Sphere values

    t, s Ti * -ln(*)

    0.0 69.97 0.997 0.003 , PVC 91.80 lbm/ft^3 , PC 74.90 lbm/ft^3

    0.5 70.10 0.994 0.006 k, PVC 0.058 Btu/hr-ft-F k, PC 0.110 Btu/hr-ft-F

    1.0 69.97 0.997 0.003 c, PVC 0.201 Btu/lbm-F c, PC 0.301 Btu/lbm-F

    1.5 70.37 0.989 0.011 , PVC 1.28E-07 , PC 1.34E-07

    2.0 69.97 0.997 0.003 Bi, PVC 443.560 Bi, PC 345.896

    2.5 70.10 0.994 0.006 1/1^2 0.1016 1/1^2 0.1018

    3.0 69.97 0.997 0.003 1 3.1366 1 3.1346

    3.5 70.10 0.994 0.006 C1 0.5024 C1 0.5033

    4.0 69.84 1.000 0.000 k, PVC 0.009 Btu/hr-ft-F k, PC 0.011 Btu/hr-ft-F

    4.5 70.10 0.994 0.006 %ER, PVC 85% %ER, PC 90%