Solutions Manual For Thermal Radiation Heat Transfer 6th
Edition By John R. Howell , M. Pinar Mengüç , Robert Siegel
9781466593268 ALL Chapters
Radiation Heat Transfer - ANSWER: Energy Transfer across a system boundary due to temperature
difference via photon emission or electromagnetic wave emission
Radiation Heat Transfer - ANSWER: The only heat transfer mechanism present in a *vacuum*
Radiation Heat Transfer - ANSWER: Fastest heat transfer mechanism
Radiation Heat Transfer - ANSWER: Can occur between bodies separated by a medium colder than
both bodies
Radiation Heat Transfer - ANSWER: Exchange of thermal radiation energy between two or more
bodies
Thermal Radiation - ANSWER: The portion of the electromagnetic spectrum found between 0.1 to 100
microns
Thermal Radiation - ANSWER: Emitted by all matter whose temperature is above absolute zero
Thermal Radiation - ANSWER: Emitted as a result of energy transitions of molecules, atoms, and
electrons of a substance
Thermal Radiation - ANSWER: The strength of the microscopic energy transition can be determined by
measuring the system's temperature
↑ rate of thermal radiation, ↑ temperature reading
Thermal Radiation - ANSWER: Important whenever a large temperature difference exists (i.e. boiler,
oven, dryer, cryogenic installations, etc.)
Thermal Radiation - ANSWER: The amount of energy transferred into or out of an object depends on
surface reflectivity, emissivity, surface area, temperature, and geometry
Incident radiation
a.k.a "irradiation" - ANSWER: Term used when referring to radiation that hit a certain surface or body
Reflectivity (r) - ANSWER: Fraction of radiation that is reflected (i.e., reflectance)
Reflectivity (r) - ANSWER: Change in direction of a wave at an interface between two different media
so that the wave returns to its source.
Specular Reflection - ANSWER: [Types of Reflection]
Occurs when the angle of the incident beam as it strikes the surface becomes equal to the angle of
the reflected beam
Specular reflection - ANSWER: [Types of Reflection]
Occurs in surfaces that are similar to mirrors
Diffuse reflection - ANSWER: [Types of Reflection]
, Occurs when the incident beam that strikes the surface becomes multiple beams reflected in various
directions
Diffuse reflection - ANSWER: [Types of Reflection]
Occurs in surfaces that have irregularities
Absorptivity (a) - ANSWER: Fraction that is absorbed by the surface (i.e. absorbance)
Transmissivity (t) - ANSWER: Fraction that passes through the surface (i.e. transmittance)
Transmissivity (t) - ANSWER: t for different surfaces:
a. Translucent or transparent surfaces à t > 0
b. Opaque surfaces à t = 0
c. Most solids and liquids à t = 0
Emissivity (e) - ANSWER: Measure of the radiation emitted by a certain surface (E) against the
maximum radiation emitted by an ideal surface (Eb). Both surfaces have the same temperature.
Formula: e = (E/Eb)
Things to remember:
a. Emissivity increases with temperature
b. Light or reflective substances have low emissivity
c. Dark or dull substances have high emissivity
.
Radiation Emitted by a Surface - ANSWER: Different surfaces emit different amounts of radiation even
when they are at the same temperature
Radiation Emitted by a Surface - ANSWER: Due to this, the radiative properties of an ideal surface
(called a "blackbody"0 are used as the standard to which the radiative properties of real surfaces may
be compared to
Blackbody - ANSWER: A hypothetical body that is a perfect emitter (i.e. e = 1) and absorber (i.e. a = 1)
of radiation
Blackbody - ANSWER: Gives the maximum amount of radiation that can be emitted by a surface
Blackbody - ANSWER: Emits radiation energy uniformly in all directions
Blackbody - ANSWER: Do not reflect light (i.e. r = 0)
Dull/Matte/Dark Surfaces - ANSWER: *Determine the Type of Surface*
Absorptivity and Emissivity:
- Higher rate of a
- Higher e
Shiny/White Surfaces - ANSWER: *Determine the Type of Surface*
Absorptivity and Emissivity:
Edition By John R. Howell , M. Pinar Mengüç , Robert Siegel
9781466593268 ALL Chapters
Radiation Heat Transfer - ANSWER: Energy Transfer across a system boundary due to temperature
difference via photon emission or electromagnetic wave emission
Radiation Heat Transfer - ANSWER: The only heat transfer mechanism present in a *vacuum*
Radiation Heat Transfer - ANSWER: Fastest heat transfer mechanism
Radiation Heat Transfer - ANSWER: Can occur between bodies separated by a medium colder than
both bodies
Radiation Heat Transfer - ANSWER: Exchange of thermal radiation energy between two or more
bodies
Thermal Radiation - ANSWER: The portion of the electromagnetic spectrum found between 0.1 to 100
microns
Thermal Radiation - ANSWER: Emitted by all matter whose temperature is above absolute zero
Thermal Radiation - ANSWER: Emitted as a result of energy transitions of molecules, atoms, and
electrons of a substance
Thermal Radiation - ANSWER: The strength of the microscopic energy transition can be determined by
measuring the system's temperature
↑ rate of thermal radiation, ↑ temperature reading
Thermal Radiation - ANSWER: Important whenever a large temperature difference exists (i.e. boiler,
oven, dryer, cryogenic installations, etc.)
Thermal Radiation - ANSWER: The amount of energy transferred into or out of an object depends on
surface reflectivity, emissivity, surface area, temperature, and geometry
Incident radiation
a.k.a "irradiation" - ANSWER: Term used when referring to radiation that hit a certain surface or body
Reflectivity (r) - ANSWER: Fraction of radiation that is reflected (i.e., reflectance)
Reflectivity (r) - ANSWER: Change in direction of a wave at an interface between two different media
so that the wave returns to its source.
Specular Reflection - ANSWER: [Types of Reflection]
Occurs when the angle of the incident beam as it strikes the surface becomes equal to the angle of
the reflected beam
Specular reflection - ANSWER: [Types of Reflection]
Occurs in surfaces that are similar to mirrors
Diffuse reflection - ANSWER: [Types of Reflection]
, Occurs when the incident beam that strikes the surface becomes multiple beams reflected in various
directions
Diffuse reflection - ANSWER: [Types of Reflection]
Occurs in surfaces that have irregularities
Absorptivity (a) - ANSWER: Fraction that is absorbed by the surface (i.e. absorbance)
Transmissivity (t) - ANSWER: Fraction that passes through the surface (i.e. transmittance)
Transmissivity (t) - ANSWER: t for different surfaces:
a. Translucent or transparent surfaces à t > 0
b. Opaque surfaces à t = 0
c. Most solids and liquids à t = 0
Emissivity (e) - ANSWER: Measure of the radiation emitted by a certain surface (E) against the
maximum radiation emitted by an ideal surface (Eb). Both surfaces have the same temperature.
Formula: e = (E/Eb)
Things to remember:
a. Emissivity increases with temperature
b. Light or reflective substances have low emissivity
c. Dark or dull substances have high emissivity
.
Radiation Emitted by a Surface - ANSWER: Different surfaces emit different amounts of radiation even
when they are at the same temperature
Radiation Emitted by a Surface - ANSWER: Due to this, the radiative properties of an ideal surface
(called a "blackbody"0 are used as the standard to which the radiative properties of real surfaces may
be compared to
Blackbody - ANSWER: A hypothetical body that is a perfect emitter (i.e. e = 1) and absorber (i.e. a = 1)
of radiation
Blackbody - ANSWER: Gives the maximum amount of radiation that can be emitted by a surface
Blackbody - ANSWER: Emits radiation energy uniformly in all directions
Blackbody - ANSWER: Do not reflect light (i.e. r = 0)
Dull/Matte/Dark Surfaces - ANSWER: *Determine the Type of Surface*
Absorptivity and Emissivity:
- Higher rate of a
- Higher e
Shiny/White Surfaces - ANSWER: *Determine the Type of Surface*
Absorptivity and Emissivity:
