東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Radiative characteristics of a thin ...

Pettegrew, Richard Dale.

Linked to FindBook

Google Book

Amazon

博客來

Radiative characteristics of a thin solid fuel at discrete levels of pyrolysis: Angular, spectral, and thermal dependencies.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Radiative characteristics of a thin solid fuel at discrete levels of pyrolysis: Angular, spectral, and thermal dependencies./
Author:	Pettegrew, Richard Dale.
Description:	194 p.
Notes:	Source: Dissertation Abstracts International, Volume: 66-10, Section: B, page: 5524.
Contained By:	Dissertation Abstracts International66-10B.
Subject:	Engineering, Aerospace. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3193557
ISBN:	9780542369889

Radiative characteristics of a thin solid fuel at discrete levels of pyrolysis: Angular, spectral, and thermal dependencies.
Pettegrew, Richard Dale.

Radiative characteristics of a thin solid fuel at discrete levels of pyrolysis: Angular, spectral, and thermal dependencies. - 194 p.

Source: Dissertation Abstracts International, Volume: 66-10, Section: B, page: 5524.

Thesis (Ph.D.)--Case Western Reserve University, 2006.

Numerical models of solid fuel combustion rely on accurate radiative property values to properly account for radiative heat transfer to and from the surface. The spectral properties can change significantly over the temperature range from ambient to burnout temperature. The variations of these properties are due to mass loss (as the sample pyrolyzes), chemical changes, and surface finish changes. In addition, band-integrated properties can vary due to the shift in the peak of the Planck curve as the temperature increases, which results in differing weightings of the spectral values. These effects were quantified for a thin cellulosic fuel commonly used in microgravity combustion studies (KimWipesRTM). Pyrolytic effects were simulated by heat-treating the samples in a constant temperature oven for varying times. Spectral data was acquired using a Fourier Transform Infrared (FTIR) spectrometer, along with an integrating sphere. Data was acquired at different incidence angles by mounting the samples at different angles inside the sphere. Comparisons of samples of similar area density created using different heat-treatment regimens showed that thermal history of the samples was irrelevant in virtually all spectral regions, with overall results correlating well with changes in area density. Spectral, angular, and thermal dependencies were determined for a representative data set, showing that the spectral absorptance decreases as the temperature increases, and decreases as the incidence angle varies from normal. Changes in absorptance are primarily offset by corresponding changes in transmittances, with reflectance values shown to be low over the tested spectral region of 2.50 mum to 24.93 mum. Band-integrated values were calculated as a function of temperature for the entire tested spectral region, as well as limited bands relevant for thermal imaging applications. This data was used to demonstrate the significant error that is likely if incorrect emittance values are used in heat transfer calculations. The pyrolyzed samples were also used to determine the activation energy and pre-exponential factor needed in the zeroth-order Arrhenius reaction, sometimes used to model the mass loss from the surface in numerical models. The values determined were used to calculate an estimated peak surface temperature, which agrees well with experimentally determined values.

ISBN: 9780542369889Subjects--Topical Terms:

1018395
Engineering, Aerospace.

Radiative characteristics of a thin solid fuel at discrete levels of pyrolysis: Angular, spectral, and thermal dependencies.
LDR:03357nmm 2200289 4500 001 1824226
005 20061128083238.5
008 130610s2006 eng d
020 $a 9780542369889
035 $a (UnM)AAI3193557
035 $a AAI3193557
040 $a UnM $c UnM
100 1 $a Pettegrew, Richard Dale. $3 1913310
245 1 0 $a Radiative characteristics of a thin solid fuel at discrete levels of pyrolysis: Angular, spectral, and thermal dependencies.
300 $a 194 p.
500 $a Source: Dissertation Abstracts International, Volume: 66-10, Section: B, page: 5524.
500 $a Adviser: James T'ien.
502 $a Thesis (Ph.D.)--Case Western Reserve University, 2006.
520 $a Numerical models of solid fuel combustion rely on accurate radiative property values to properly account for radiative heat transfer to and from the surface. The spectral properties can change significantly over the temperature range from ambient to burnout temperature. The variations of these properties are due to mass loss (as the sample pyrolyzes), chemical changes, and surface finish changes. In addition, band-integrated properties can vary due to the shift in the peak of the Planck curve as the temperature increases, which results in differing weightings of the spectral values. These effects were quantified for a thin cellulosic fuel commonly used in microgravity combustion studies (KimWipesRTM). Pyrolytic effects were simulated by heat-treating the samples in a constant temperature oven for varying times. Spectral data was acquired using a Fourier Transform Infrared (FTIR) spectrometer, along with an integrating sphere. Data was acquired at different incidence angles by mounting the samples at different angles inside the sphere. Comparisons of samples of similar area density created using different heat-treatment regimens showed that thermal history of the samples was irrelevant in virtually all spectral regions, with overall results correlating well with changes in area density. Spectral, angular, and thermal dependencies were determined for a representative data set, showing that the spectral absorptance decreases as the temperature increases, and decreases as the incidence angle varies from normal. Changes in absorptance are primarily offset by corresponding changes in transmittances, with reflectance values shown to be low over the tested spectral region of 2.50 mum to 24.93 mum. Band-integrated values were calculated as a function of temperature for the entire tested spectral region, as well as limited bands relevant for thermal imaging applications. This data was used to demonstrate the significant error that is likely if incorrect emittance values are used in heat transfer calculations. The pyrolyzed samples were also used to determine the activation energy and pre-exponential factor needed in the zeroth-order Arrhenius reaction, sometimes used to model the mass loss from the surface in numerical models. The values determined were used to calculate an estimated peak surface temperature, which agrees well with experimentally determined values.
590 $a School code: 0042.
650 4 $a Engineering, Aerospace. $3 1018395
650 4 $a Physics, Radiation. $3 1019212
650 4 $a Chemistry, Radiation. $3 1017804
690 $a 0538
690 $a 0756
690 $a 0754
710 2 0 $a Case Western Reserve University. $3 1017714
773 0 $t Dissertation Abstracts International $g 66-10B.
790 1 0 $a T'ien, James, $e advisor
790 $a 0042
791 $a Ph.D.
792 $a 2006
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3193557