Analytical model for the design of volumetric solar flow receivers

Ananthanarayanan Veeraragavan; Andrej Lenert; Bekir Yilbas; Salem Al-Dini; Evelyn N. Wang

doi:10.1016/j.ijheatmasstransfer.2011.11.001

Analytical model for the design of volumetric solar flow receivers

Ananthanarayanan Veeraragavan, Andrej Lenert, Bekir Yilbas, Salem Al-Dini, Evelyn N. Wang^*

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

117 Scopus citations

Abstract

The development of efficient solar thermal receivers has received significant interest for solar to electrical power conversion and heating applications. Volumetric flow receivers, where the incoming solar radiation is absorbed in the volume of a heat transfer fluid (HTF), promise reduced heat loss at the surface compared to surface absorbers. In order to efficiently store the thermal energy in the volume, nanoparticles can be suspended in the HTF to absorb the incoming radiation. In such systems, compact models are needed to design and optimize the performance. This paper presents an analytical model that investigates the effect of heat loss, particle loading, solar concentration and channel height on receiver efficiency. The analytical model was formulated by modeling the absorption of solar radiation by the suspended nanoparticles as a volumetric heat release inside the flowing HTF. The energy equation was solved with the surface heat losses modeled using a combined radiative and convective heat loss coefficient. The analytical solution provides a convenient tool for predicting the effect of different parameters, in terms of dimensionless numbers (Pe, Nu_E, G, and θ_amb), on two-dimensional temperature profiles and system performance. By combining the receiver efficiency with a power generation efficiency, idealized by the Carnot efficiency, an optimum receiver length where the total efficiency is maximized is determined. However, in practice, the maximum efficiency depends on the maximum allowable temperature of the working HTF. As a case study, predictions were made for Therminol® VP-1 with suspended graphite nanoparticles in a 1 cm deep channel with a solar concentration of 10. The model predicts an optimum total system efficiency of 0.35 for a dimensionless receiver length of 0.86. Finally, the analytical model was used to estimate the optimum efficiency and the corresponding optimum receiver length for different design configurations with varying Nu_E and G. The results from this paper will help guide experimental design of volumetric flow receivers for solar thermal based power systems.

Original language	English
Pages (from-to)	556-564
Number of pages	9
Journal	International Journal of Heat and Mass Transfer
Volume	55
Issue number	4
DOIs	https://doi.org/10.1016/j.ijheatmasstransfer.2011.11.001
State	Published - 31 Jan 2012

Bibliographical note

Funding Information:
The authors would like to thank the King Fahd University of Petroleum and Minerals in Dhahran, Saudi Arabia, for funding the research reported in this paper through the Center for Clean Water and Clean Energy at MIT and KFUPM. Also, Andrej Lenert acknowledges the support of the MIT Energy Initiative and the National Science Foundation Graduate Fellowship.

Keywords

Analytical model
Energy conversion
Heat transfer fluid
Nanoparticles
Solar thermal
Volumetric receiver

ASJC Scopus subject areas

Condensed Matter Physics
Mechanical Engineering
Fluid Flow and Transfer Processes

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1016/j.ijheatmasstransfer.2011.11.001

Cite this

@article{452e7828a1b14bd6a3d25a5b879cff45,

title = "Analytical model for the design of volumetric solar flow receivers",

abstract = "The development of efficient solar thermal receivers has received significant interest for solar to electrical power conversion and heating applications. Volumetric flow receivers, where the incoming solar radiation is absorbed in the volume of a heat transfer fluid (HTF), promise reduced heat loss at the surface compared to surface absorbers. In order to efficiently store the thermal energy in the volume, nanoparticles can be suspended in the HTF to absorb the incoming radiation. In such systems, compact models are needed to design and optimize the performance. This paper presents an analytical model that investigates the effect of heat loss, particle loading, solar concentration and channel height on receiver efficiency. The analytical model was formulated by modeling the absorption of solar radiation by the suspended nanoparticles as a volumetric heat release inside the flowing HTF. The energy equation was solved with the surface heat losses modeled using a combined radiative and convective heat loss coefficient. The analytical solution provides a convenient tool for predicting the effect of different parameters, in terms of dimensionless numbers (Pe, NuE, G, and θamb), on two-dimensional temperature profiles and system performance. By combining the receiver efficiency with a power generation efficiency, idealized by the Carnot efficiency, an optimum receiver length where the total efficiency is maximized is determined. However, in practice, the maximum efficiency depends on the maximum allowable temperature of the working HTF. As a case study, predictions were made for Therminol{\textregistered} VP-1 with suspended graphite nanoparticles in a 1 cm deep channel with a solar concentration of 10. The model predicts an optimum total system efficiency of 0.35 for a dimensionless receiver length of 0.86. Finally, the analytical model was used to estimate the optimum efficiency and the corresponding optimum receiver length for different design configurations with varying NuE and G. The results from this paper will help guide experimental design of volumetric flow receivers for solar thermal based power systems.",

keywords = "Analytical model, Energy conversion, Heat transfer fluid, Nanoparticles, Solar thermal, Volumetric receiver",

author = "Ananthanarayanan Veeraragavan and Andrej Lenert and Bekir Yilbas and Salem Al-Dini and Wang, \{Evelyn N.\}",

note = "Funding Information: The authors would like to thank the King Fahd University of Petroleum and Minerals in Dhahran, Saudi Arabia, for funding the research reported in this paper through the Center for Clean Water and Clean Energy at MIT and KFUPM. Also, Andrej Lenert acknowledges the support of the MIT Energy Initiative and the National Science Foundation Graduate Fellowship. ",

year = "2012",

month = jan,

day = "31",

doi = "10.1016/j.ijheatmasstransfer.2011.11.001",

language = "English",

volume = "55",

pages = "556--564",

journal = "International Journal of Heat and Mass Transfer",

issn = "0017-9310",

number = "4",

}

TY - JOUR

T1 - Analytical model for the design of volumetric solar flow receivers

AU - Veeraragavan, Ananthanarayanan

AU - Lenert, Andrej

AU - Yilbas, Bekir

AU - Al-Dini, Salem

AU - Wang, Evelyn N.

N1 - Funding Information: The authors would like to thank the King Fahd University of Petroleum and Minerals in Dhahran, Saudi Arabia, for funding the research reported in this paper through the Center for Clean Water and Clean Energy at MIT and KFUPM. Also, Andrej Lenert acknowledges the support of the MIT Energy Initiative and the National Science Foundation Graduate Fellowship.

PY - 2012/1/31

Y1 - 2012/1/31

N2 - The development of efficient solar thermal receivers has received significant interest for solar to electrical power conversion and heating applications. Volumetric flow receivers, where the incoming solar radiation is absorbed in the volume of a heat transfer fluid (HTF), promise reduced heat loss at the surface compared to surface absorbers. In order to efficiently store the thermal energy in the volume, nanoparticles can be suspended in the HTF to absorb the incoming radiation. In such systems, compact models are needed to design and optimize the performance. This paper presents an analytical model that investigates the effect of heat loss, particle loading, solar concentration and channel height on receiver efficiency. The analytical model was formulated by modeling the absorption of solar radiation by the suspended nanoparticles as a volumetric heat release inside the flowing HTF. The energy equation was solved with the surface heat losses modeled using a combined radiative and convective heat loss coefficient. The analytical solution provides a convenient tool for predicting the effect of different parameters, in terms of dimensionless numbers (Pe, NuE, G, and θamb), on two-dimensional temperature profiles and system performance. By combining the receiver efficiency with a power generation efficiency, idealized by the Carnot efficiency, an optimum receiver length where the total efficiency is maximized is determined. However, in practice, the maximum efficiency depends on the maximum allowable temperature of the working HTF. As a case study, predictions were made for Therminol® VP-1 with suspended graphite nanoparticles in a 1 cm deep channel with a solar concentration of 10. The model predicts an optimum total system efficiency of 0.35 for a dimensionless receiver length of 0.86. Finally, the analytical model was used to estimate the optimum efficiency and the corresponding optimum receiver length for different design configurations with varying NuE and G. The results from this paper will help guide experimental design of volumetric flow receivers for solar thermal based power systems.

AB - The development of efficient solar thermal receivers has received significant interest for solar to electrical power conversion and heating applications. Volumetric flow receivers, where the incoming solar radiation is absorbed in the volume of a heat transfer fluid (HTF), promise reduced heat loss at the surface compared to surface absorbers. In order to efficiently store the thermal energy in the volume, nanoparticles can be suspended in the HTF to absorb the incoming radiation. In such systems, compact models are needed to design and optimize the performance. This paper presents an analytical model that investigates the effect of heat loss, particle loading, solar concentration and channel height on receiver efficiency. The analytical model was formulated by modeling the absorption of solar radiation by the suspended nanoparticles as a volumetric heat release inside the flowing HTF. The energy equation was solved with the surface heat losses modeled using a combined radiative and convective heat loss coefficient. The analytical solution provides a convenient tool for predicting the effect of different parameters, in terms of dimensionless numbers (Pe, NuE, G, and θamb), on two-dimensional temperature profiles and system performance. By combining the receiver efficiency with a power generation efficiency, idealized by the Carnot efficiency, an optimum receiver length where the total efficiency is maximized is determined. However, in practice, the maximum efficiency depends on the maximum allowable temperature of the working HTF. As a case study, predictions were made for Therminol® VP-1 with suspended graphite nanoparticles in a 1 cm deep channel with a solar concentration of 10. The model predicts an optimum total system efficiency of 0.35 for a dimensionless receiver length of 0.86. Finally, the analytical model was used to estimate the optimum efficiency and the corresponding optimum receiver length for different design configurations with varying NuE and G. The results from this paper will help guide experimental design of volumetric flow receivers for solar thermal based power systems.

KW - Analytical model

KW - Energy conversion

KW - Heat transfer fluid

KW - Nanoparticles

KW - Solar thermal

KW - Volumetric receiver

UR - https://www.scopus.com/pages/publications/82955203466

U2 - 10.1016/j.ijheatmasstransfer.2011.11.001

DO - 10.1016/j.ijheatmasstransfer.2011.11.001

M3 - Article

AN - SCOPUS:82955203466

SN - 0017-9310

VL - 55

SP - 556

EP - 564

JO - International Journal of Heat and Mass Transfer

JF - International Journal of Heat and Mass Transfer

IS - 4

ER -

Analytical model for the design of volumetric solar flow receivers

Abstract

Bibliographical note

Keywords

ASJC Scopus subject areas

UN SDGs

Access to Document

Fingerprint

Cite this