Three-dimensional numerical study of direct steam generation in vertical tubes receiving concentrated solar radiation

In summer, the temperature of a parked automobile compartment increases extremely high under a sunny condition. Investigation of this fluid flow and heat transfer characteristics is very important for controlling the effect of major design parameters. This paper address the behavior of fluid flow through convection and air temperature inside a car parked in the sun. The numerical solution was done by a new and operation friendly CFD code – SC/Tetra with a full scale model of a SM3 car and turbulence was modeled by the standard k-ε equation. It can be seen that solar radiation is an important parameter to raise the compartment temperature above the ambient temperature during summer. Numerical analysis of the three-dimensional model predicts a detailed description of fluid flow and temperature distribution driven by the incoming solar radiation (insoaltion) in the passenger compartment.

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Fast Pyrolysis of Biomass Pellets Using Concentrated Solar Radiation: A Numerical Study

Journal of Solar Energy Engineering ◽

10.1115/1.4027266 ◽

2014 ◽

Vol 136 (4) ◽

Cited By ~ 6

Author(s):

Saeed Danaei Kenarsari ◽

Yuan Zheng

Keyword(s):

Solar Radiation ◽

Numerical Study ◽

Fast Pyrolysis ◽

Mountain Pine Beetles ◽

Pyrolysis Products ◽

Pine Trees ◽

Secondary Reactions ◽

Concentrated Solar Radiation ◽

Pyrolysis Of Biomass ◽

Pine Beetles

Since the 1990s, mountain pine beetles have infested mature pine trees in the forests of western North America. Fast pyrolysis is an encouraging method to convert the beetle killed pine trees into bio-oils. In this study, an unsteady-state mathematical model is developed to simulate fast pyrolysis under concentrated solar radiation. Conservation equations of total mass, species, and energy, coupled with the chemical kinetics model, have been developed and solved to simulate fast pyrolysis of cylindrical biomass pellets in a quartz reactor exposed to various radiant heating fluxes. This study demonstrates the importance of the secondary reactions on fast pyrolysis products.

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Numerical study of heat transfer enhancement in the receiver tube of direct steam generation with parabolic trough by inserting metal foams

Applied Energy ◽

10.1016/j.apenergy.2012.07.026 ◽

2013 ◽

Vol 102 ◽

pp. 449-460 ◽

Cited By ~ 134

Author(s):

P. Wang ◽

D.Y. Liu ◽

C. Xu

Keyword(s):

Heat Transfer ◽

Heat Transfer Enhancement ◽

Numerical Study ◽

Metal Foams ◽

Steam Generation ◽

Transfer Enhancement ◽

Parabolic Trough ◽

Direct Steam

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Numerical study of circumferential temperature difference reduction at the absorber tube of parabolic trough direct steam generation collector by inserting a twisted tape in superheated region

Case Studies in Thermal Engineering ◽

10.1016/j.csite.2020.100720 ◽

2020 ◽

Vol 21 ◽

pp. 100720

Author(s):

S.Mostafa Hosseinalipour ◽

Ali Rostami ◽

Gholamreza Shahriari

Keyword(s):

Temperature Difference ◽

Numerical Study ◽

Twisted Tape ◽

Steam Generation ◽

Parabolic Trough ◽

Direct Steam

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Three-Dimensional Analysis of a Concentrated Solar Flux

Journal of Solar Energy Engineering ◽

10.1115/1.2807212 ◽

2008 ◽

Vol 130 (1) ◽

Cited By ~ 15

Author(s):

David Riveros-Rosas ◽

Marcelino Sánchez-González ◽

Claudio A. Estrada

Keyword(s):

Thermal Stress ◽

Solar Radiation ◽

Computer Program ◽

Ray Tracing ◽

Solar Irradiance ◽

Radiation Flux ◽

Three Dimensional ◽

Mirror Surface ◽

Concentrated Solar Radiation ◽

Focal Zone

In order to improve the durability of receivers used in solar concentrating systems, it is necessary to minimize thermal stress during their operation. A possible way to do that is to design receivers in which the radiative flux density is homogeneous at the surface. For this reason, a detailed 3D study has been carried out for the distribution of concentrated solar radiation in the focal zone of a parabolic concentrator. A computer program has been developed to obtain isosurfaces of solar irradiance and achieve a homogeneous radiation flux on the receiver surface. The algorithm of the program proposes a methodology to obtain flux isosurfaces for a great variety of optical configurations. The effect of the optical errors on the mirror surface has been studied, as well as the effect of the shape of the mirror, e.g., round, square, or faceted. The numerical calculations were made using the convolution ray tracing technique.

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