China
Africa
Explore chapters and articles related to this topic
Properties of Participating Media
Published in John R. Howell, M. Pinar Mengüç, Kyle Daun, Robert Siegel, Thermal Radiation Heat Transfer, 2020
John R. Howell, M. Pinar Mengüç, Kyle Daun, Robert Siegel
Some of the applications of radiative transfer in participating media are energy transfer through hot gases and particles in engines and combustion chambers at high pressures and temperatures. Examples include rocket propulsion, glass manufacturing, fibrous insulating layers, nuclear explosions, hypersonic shock layers, plasma generators for nuclear fusion, ablating thermal protection systems, translucent ceramics at high temperature, irradiation of biological systems, and heat transfer in porous materials.
Principles and Applications of UV Light Technology
Published in Tatiana Koutchma, Ultraviolet Light in Food Technology, 2019
Surprisingly, little is known about the interaction of UV light with matter, especially with a complex food matrix, considering its importance. Radiative transfer covers all processes in which light or other electromagnetic energy is emitted or radiated with some of this energy transferred from one form to another, as it is in scattering and absorption. The particular type of interaction taking place in a liquid matrix can often be referred to as radiative transfer in a transparent, semi-transparent, or turbid medium. A turbid medium is defined as a substance which both scatters and absorbs part of the light falling on it. All translucent and opaque materials are, therefore, turbid media.
Introductory Theory
Published in Robert P. Bukata, John H. Jerome, Kirill Ya. Kondratyev, Dimitry V. Pozdnyakov, of Inland and Coastal Waters, 2018
Robert P. Bukata, John H. Jerome, Kirill Ya. Kondratyev, Dimitry V. Pozdnyakov
In its most simplistic concept, radiative transfer is the dynamics of the energy changes associated with the propagation of radiation through media which absorb, scatter, and/or emit photons. It would, therefore, be most advantageous if radiative transfer could be considered in terms of appropriate manipulations of the absorption, scattering, and total attenuation coefficients pertinent to the media [that is, the optical properties, a(λ), b(λ), and c(λ)]. In order to do so, such optical properties should be independent of the manner in which they are being measured as well as independent of the manner in which the medium under observation is being illuminated. Such optical properties, therefore, should be inherent optical properties of the medium, that is, independent of the radiation distribution within that medium. All three of the optical properties a(λ), b(λ), and c(λ) qualify as inherent optical properties of the medium. Under in situ conditions, the total attenuation coefficient c(λ) for natural waters is generally directly measured by means of submersible transmissometers. The scattering coefficient b(λ) may be inferred through indirect measurements [e.g., as discussed below, from measurements of the volume scattering function β(θ)]. The absorption coefficient a(λ) is then obtained as the difference between c(λ) and b(λ)..
Numerical investigation of solar flat plate collector using different working fluids
Published in International Journal of Ambient Energy, 2023
Pragya Narayana Prasad, Sarita Kalla
A radiative transfer equation mathematically describes the interactions of radiation within media in terms of absorption, emission, and scattering. It has the following components: (i) energy loss due to absorption, (ii) energy gain due to emission, and (iii) energy redistribution due to scattering, taking into consideration the directional dependence of radiations (Ekramian, Etemad, and Haghshenasfard 2014). The P-1 radiation model was activated to simulate the SFPC, which assumes that the directional dependence in the radiative transfer equation is integrated out and results in a diffusion equation for incident radiation (Selvakumar et al. 2019). The main advantage of this model is that the radiative transfer equation is easy to solve with less CPU demand. The model includes the effects of scattering due to the presence of particles, droplets, and soot. The direct solar irradiation is 1500 W/m2, and diffuse solar irradiation is 250 W/m2.
Auto-adaptive Tikhonov regularization of water vapor profiles: application to FORUM measurements
Published in Applicable Analysis, 2022
L. Sgheri, P. Raspollini, M. Ridolfi
The radiative transfer models the intensity of radiation as it travels through a mean such as the atmosphere. The inhomogeneous atmosphere is usually discretized in small elements which are assumed to be homogeneous. The source of the ill-conditioning of the inverse problem lies in the Lambert–Beer law: where is the intensity at spatial coordinate z, and is a frequency-dependent constant. Equation (1) has the general solution . The constant contains the concentrations of the atmospheric constituents of the homogeneous mean, which are also parameters of the inversion problem. For a broader discussion, see [17].
Remote sensing of earth’s energy budget: synthesis and review
Published in International Journal of Digital Earth, 2019
Shunlin Liang, Dongdong Wang, Tao He, Yunyue Yu
Cheng, Liang, and Wang (2017) reviewed various estimation methods for generating the products from satellite remote sensing, including radiative transfer calculation with atmospheric profiles and parameterization. If the atmospheric profiles are known from surface radiosonde, a radiosonde balloon, or derived from satellite sounding data, a radiative transfer model can be used to calculate the downward longwave radiation (Darnell, Gupta, and Staylor 1986; Frouin, Gautier, and Morcrette 1988). The radiative transfer model needs to be computationally efficient and the generated products largely depend largely on the accuracy of atmospheric temperature and moisture profiles. The satellite products from remote sensing data include the ISCCP-FD, GEWEX, and CERES products that have temporal and similar spatial resolutions to other EEB components discussed earlier. In addition, the EUMETSAT CM-SAF also produces the monthly longwave downward radiation product by merging AVHRR and SEVERI data (Schulz et al. 2009) with a spatial resolution of 15 km.