Thermodynamics of the conversion of diluted radiation

Landsberg, P. T.; Tonge, G.

doi:10.1088/0305-4470/12/4/015

Cited by 116 publications

(95 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The expression for exergy of solar radiation and the history of its development have also been investigated and documented more recently by various authors [42, 51 -56]. Throughout the literature [57 -60] the absorbed solar radiation exergy rate, considering the Petela theorem [61], is given by The expression for * / s s T T , relating the effective temperature of diffuse radiation to the solar temperature, is obtained from Landsberg and Tonge [63], with ĸ, the dilution factor of diffuse radiation, less than 0.1.…”

Section: The Sun As An Exergy Sourcementioning

confidence: 99%

A review on the thermodynamic optimisation and modelling of the solar thermal Brayton cycle

Roux

Bello‐Ochende

Meyer

2013

Renewable and Sustainable Energy Reviews

View full text Add to dashboard Cite

Many studies have been published on the performance and optimisation of the Brayton cycle and solar thermal Brayton cycle showing the potential, merits and challenges of this technology. Solar thermal Brayton systems have potential to be used as power plants in many sun-drenched countries. It can be very competitive in terms of efficiency, cost and environmental impact. When designing a system such as a recuperative Brayton cycle there is always a compromise between allowing effective heat transfer and keeping pressure losses in components small. The high temperatures required in especially the receiver of the system presents a challenge in terms of irreversibilities due to heat loss. In this paper, the authors recommend the use of the total entropy generation minimisation method. This method can be applied for the modelling of a system and can serve as validation when compared with first-law modelling. The authors review various modelling perspectives required to develop an objective function for solar thermal power optimisation, including modelling of the sun as an exergy source, the Gouy-Stodola theorem and turbine modelling.With recommendations, the authors of this paper wish to clarify and simplify the optimisation and modelling of the solar thermal Brayton cycle for future work. The work is applicable to solar thermal studies in general but focuses on the small-scale recuperated solar thermal Brayton cycle.2

show abstract

Section: The Sun As An Exergy Sourcementioning

confidence: 99%

A review on the thermodynamic optimisation and modelling of the solar thermal Brayton cycle

Roux

Bello‐Ochende

Meyer

2013

Renewable and Sustainable Energy Reviews

View full text Add to dashboard Cite

show abstract

“…The entropy formula for grey body radiation is given by Landsberg and Tonge [15] as: An approximation of this function (20) for an error less than 2% value of reads 1 ( ) 0,965157 0, 2776566 ln 0, 05115…”

Section: Entropy Production Upon Absorption and Emission Of Radiationmentioning

confidence: 99%

Entropy Generation During the Interaction of Thermal Radiation with a Surface

Kabelac

Conrad

2012

Entropy

View full text Add to dashboard Cite

Abstract:The entropy calculation for radiation fluxes is reviewed and applied to simple radiation-surface interactions. A plate interacting with radiation from a hot object in the zenith of the hemisphere surrounded by a colder atmosphere is analyzed in detail. The entropy generation rate upon absorption and reflection of the incoming radiation is calculated and discussed. The plate is adiabatic in a first version (thermal equilibrium), then its temperature is fixed by allowing a heat flux to or from the plate. This analysis prepares the way towards an entropy generation minimization analysis of more complex radiation settings.

show abstract

“…Methodology in calculation of non-blackbody radiation entropy flux has attracted much attention of many different fields (such as Engineering or the Earth Sciences) for several decades and various expressions have been developed (e.g. Petela 1964Petela , 2003Landsberg & Tonge 1979;Stephens & O'Brien 1993;Wright et al 2001;Zhang & Basu 2007). We have recently examined the performance of major analytical expressions for calculating radiation entropy flux and the associated approximations (Wu & Liu in press), finding that the expression proposed by Wright et al (2001) exhibits the best overall performance among all the approximate expressions in the calculation of the Earth's LW radiation entropy flux under the assumption that the Earth's LW radiation emission behaves as a greybody.…”

Section: Theoretical Frameworkmentioning

confidence: 99%

A new one-dimensional radiative equilibrium model for investigating atmospheric radiation entropy flux

Liu

2010

Phil. Trans. R. Soc. B

View full text Add to dashboard Cite

A new one-dimensional radiative equilibrium model is built to analytically evaluate the vertical profile of the Earth's atmospheric radiation entropy flux under the assumption that atmospheric longwave radiation emission behaves as a greybody and shortwave radiation as a diluted blackbody. Results show that both the atmospheric shortwave and net longwave radiation entropy fluxes increase with altitude, and the latter is about one order in magnitude greater than the former. The vertical profile of the atmospheric net radiation entropy flux follows approximately that of the atmospheric net longwave radiation entropy flux. Sensitivity study further reveals that a 'darker' atmosphere with a larger overall atmospheric longwave optical depth exhibits a smaller net radiation entropy flux at all altitudes, suggesting an intrinsic connection between the atmospheric net radiation entropy flux and the overall atmospheric longwave optical depth. These results indicate that the overall strength of the atmospheric irreversible processes at all altitudes as determined by the corresponding atmospheric net entropy flux is closely related to the amount of greenhouse gases in the atmosphere.

show abstract

Thermodynamics of the conversion of diluted radiation

Cited by 116 publications

References 7 publications

A review on the thermodynamic optimisation and modelling of the solar thermal Brayton cycle

A review on the thermodynamic optimisation and modelling of the solar thermal Brayton cycle

Entropy Generation During the Interaction of Thermal Radiation with a Surface

A new one-dimensional radiative equilibrium model for investigating atmospheric radiation entropy flux

Contact Info

Product

Resources

About