Heat transfer model for thermal performance analysis of parabolic trough solar collectors using nanofluids

2018 ◽  
Vol 125 ◽  
pp. 334-343 ◽  
Author(s):  
Pablo D. Tagle-Salazar ◽  
K.D.P. Nigam ◽  
Carlos I. Rivera-Solorio
Keyword(s):  
Heat Transfer ◽  
Performance Analysis ◽  
Thermal Performance ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Solar Collectors ◽  
Parabolic Trough

Simplified heat transfer model for parabolic trough solar collectors using supercritical CO2

2019 ◽  
Vol 196 ◽  
pp. 807-820 ◽  
Author(s):  
Rafael Aguilar ◽  
Loreto Valenzuela ◽  
Antonio L. Avila-Marin ◽  
Pedro L. Garcia-Ybarra
Keyword(s):  
Heat Transfer ◽  
Supercritical Co2 ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Solar Collectors ◽  
Parabolic Trough

Experimental Investigation of Heat Transfer in Impingement Air Cooled Plate Fin Heat Sinks

2005 ◽  
Vol 128 (4) ◽  
pp. 412-418 ◽  
Author(s):  
Zhipeng Duan ◽  
Y. S. Muzychka
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Thermal Resistance ◽  
Thermal Performance ◽  
Heat Transfer Model ◽  
Heat Sinks ◽  
Transfer Model ◽  
Transfer Coefficients ◽  
Developing Flow ◽  
Rectangular Channels

Impingement cooling of plate fin heat sinks is examined. Experimental measurements of thermal performance were performed with four heat sinks of various impingement inlet widths, fin spacings, fin heights, and airflow velocities. The percent uncertainty in the measured thermal resistance was a maximum of 2.6% in the validation tests. Using a simple thermal resistance model based on developing laminar flow in rectangular channels, the actual mean heat transfer coefficients are obtained in order to develop a simple heat transfer model for the impingement plate fin heat sink system. The experimental results are combined into a dimensionless correlation for channel average Nusselt number Nu∼f(L*,Pr). We use a dimensionless thermal developing flow length, L*=(L∕2)∕(DhRePr), as the independent parameter. Results show that Nu∼1∕L*, similar to developing flow in parallel channels. The heat transfer model covers the practical operating range of most heat sinks, 0.01<L*<0.18. The accuracy of the heat transfer model was found to be within 11% of the experimental data taken on four heat sinks and other experimental data from the published literature at channel Reynolds numbers less than 1200. The proposed heat transfer model may be used to predict the thermal performance of impingement air cooled plate fin heat sinks for design purposes.

Nonuniform heat transfer model and performance of parabolic trough solar receiver

Energy ◽  
2013 ◽  
Vol 59 ◽  
pp. 666-675 ◽  
Author(s):  
Jianfeng Lu ◽  
Jing Ding ◽  
Jianping Yang ◽  
Xiaoxi Yang
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Parabolic Trough ◽  
And Performance ◽  
Solar Receiver

Applicability of Heat Mirrors in Reducing Thermal Losses in Concentrating Solar Collectors

2016 ◽  
Author(s):  
Prashant Mahendra ◽  
Vikrant Khullar ◽  
Madhup Mittal
Keyword(s):  
Heat Transfer ◽  
Thermal Efficiency ◽  
Solar Irradiance ◽  
Solar Collector ◽  
Flux Distribution ◽  
Heat Transfer Analysis ◽  
Transfer Model ◽  
Solar Collectors ◽  
Parabolic Trough ◽  
Glass Envelope

Flux distribution around the parabolic trough receiver being typically non-uniform, only a certain portion of the receiver circumference receives the concentrated solar irradiance. However, radiative and convective losses occur across the entire receiver circumference. This paper attempts to introduce the idea employing transparent heat mirror to effectively reduce the heat loss area and thus improve the thermal efficiency of the solar collector. Transparent heat mirror essentially has high transmissivity in the solar irradiance wavelength band and high reflectivity in the mid-infrared region thus it allows the solar irradiance to pass through but reflects the infrared radiation back to the solar selective metal tube. Practically, this could be realized if certain portion of the conventional low iron glass envelope is coated with Sn-In2O3 so that its acts as a heat mirror. In the present study, a parabolic receiver design employing the aforesaid concept has been proposed. Detailed heat transfer model has been formulated. The results of the model were compared with the experimental results of conventional concentrating parabolic trough solar collectors in the literature. It was observed that while maintaining the same external conditions (such as ambient/initial temperatures, wind speed, solar insolation, flow rate, concentration ratio etc.) the heat mirror-based parabolic trough concentrating solar collector has about 3–12% higher thermal efficiency as compared to the conventional parabolic solar collector. Furthermore, steady state heat transfer analysis reveals that depending on the solar flux distribution there is an optimum circumferential angle (θ = θoptimum, where θ is the heat mirror circumferential angle) up to which the glass envelope should be coated with Sn-In2O3. For angles higher than the optimum angle, the collector efficiency tends to decrease owing to increase in optical losses.

Heat Efficiency of Trough Solar Vacuum Receiver

2014 ◽  
Vol 521 ◽  
pp. 23-27
Author(s):  
Jun Ming Liang ◽  
Jian Feng Lu ◽  
Jing Ding ◽  
Jian Ping Yang
Keyword(s):  
Heat Transfer ◽  
Solar Radiation ◽  
Heat Loss ◽  
Wall Temperature ◽  
Radiation Flux ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Parabolic Trough ◽  
Heat Efficiency ◽  
Solar Radiation Flux

The heat loss and thermal performance of solar parabolic trough vacuum receiver were experimentally measured and analyzed by heat transfer model. According to the present experiments, the heat loss of solar parabolic trough vacuum receiver has good agreement with the heat loss of vacuum receiver from Solel company. As the wall temperature increase from 108°C to 158°C, the heat loss of solar parabolic trough vacuum receiver remarkably increases from 35 Wm-2to 57 Wm-2. The heat transfer model of parabolic trough solar receiver is then theoretically investigated due to the energy balances between the heat transfer fluid, absorber tube, glass envelope and surroundings. When solar radiation flux is constant, the heat efficiency of solar parabolic trough system decreases with the wall temperature and oil temperature. When solar radiation flux or solar concentration ratio increases, the heat efficiency of solar parabolic trough system increases.

Analysis of Electric Performance and Optimization of Trough Concentrating Solar Thermoelectric Cogeneration System

2013 ◽  
Vol 368-370 ◽  
pp. 1209-1213
Author(s):  
Zhi Ping Chen ◽  
Ming Li ◽  
Xu Ji ◽  
Xi Luo
Keyword(s):  
Heat Transfer ◽  
Thermal Performance ◽  
Performance Optimization ◽  
Heat Transfer Process ◽  
Working Fluid ◽  
Transfer Model ◽  
Experimental Basis ◽  
Parabolic Trough ◽  
One Dimensional ◽  
Cogeneration System

This study introduced the basic situation of the parabolic trough concentrating solar cogeneration system, and set a one-dimensional steady-state mathematical heat transfer model based on the experimental devices, at the same time clarified influencing factors of the major heat transfer process and thermal performance of the system. The article did perspectives theoretical analysis and simulation for the system in different aspects, through using of solar trough concentrator reflecting device, established thermal performance experiments that water as the working fluid flow, provided theoretical and experimental basis for the thermal performance optimization of the system.

A semi-dynamic heat transfer model of hollow block ventilated wall for thermal performance prediction

2017 ◽  
Vol 134 ◽  
pp. 285-294 ◽  
Author(s):  
Jinghua Yu ◽  
Junchao Huang ◽  
Xinhua Xu ◽  
Hong Ye ◽  
Chao Xiong ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Performance ◽  
Performance Prediction ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Hollow Block ◽  
Dynamic Heat Transfer
Sign in / Sign up

Export Citation Format

Share Document