scholarly journals The effect of psychrometry on the performance of a solar collector

2021 ◽  
Author(s):  
Alok Dhaundiyal ◽  
Gedion H. Gebremicheal
Keyword(s):  
Solar Radiation ◽  
Solar Collector ◽  
Thermal Design ◽  
Specific Humidity ◽  
Entropy Generation Rate ◽  
Stagnation Temperature ◽  
Absorber Plate ◽  
Carrier Fluid ◽  
Collector Plate ◽  
Flow Energy

AbstractThe investigation of a solar collector is based on the thermal behaviour of a carrier fluid and the degradation of energy across a flat plate collector. The exergy analysis of a thermal system includes the change in the exergy function of a carrier fluid while transferring solar radiation across an air gap. The cell cast acrylic glass was used to transmit the incident solar radiation to the absorber plate, and to safeguard the absorber plate from the outside environment. With the help of the steady flow energy equation, the enthalpy of the carrier fluid (moist air) was calculated. The specific humidity of the incoming air was calculated at an average dry bulb temperature of 299.4 K. The stagnation temperature at a limiting condition was also estimated to find out the maximum permissible limit for a given thermal design. The mass flow rate of air was assumed to be 5.2 g-s−1. The efficiency of the solar collector was found to vary from 40 to 42%, whereas the thermal energy available for drying was 15–59% of the exergy of the carrier fluid. The net entropy generation rate due to the collector plate was calculated to be 0.12 W-K−1.

scholarly journals Entropy generation analysis for the design of a flat plate solar collector with fins

DYNA ◽  
2020 ◽  
Vol 87 (212) ◽  
pp. 199-208
Author(s):  
Milton Muñoz ◽  
Manuel Roa ◽  
Rodrigo Correa
Keyword(s):  
Flat Plate ◽  
Entropy Generation ◽  
Solar Collector ◽  
Entropy Generation Rate ◽  
Design Parameters ◽  
Outlet Temperature ◽  
Minimum Entropy ◽  
Airflow Velocity ◽  
Collector Plate ◽  
Flat Plate Solar Collector

This article describes the optimal design of a flat-plate solar collector with fins, based on the minimum entropy generation criterion. The design parameters were optimized, considering entropy generation due to heat transfer and airflow. The latter has not been considered in previous works. The flat plate in the collector is assimilated to a finned heat sink. The dimensionless entropy generation variation is analyzed to increase values of the number of fins, as well as for different plate thicknesses and heights. We also considered variations in airflow velocity. Our data shows that airflow velocity greatly influences entropy generation. Values other than the optimum found, caused a considerable growth of total entropy. For a collector area of 4 m2, and an outlet temperature of 50°C, the optimum parameters that minimize the entropy generation rate were: 9 fins on each side of the collector plate, a height of 5 x10-2 m, a thickness of 25x10-3m, and an air velocity variable between 0.015 and 0.046 m/s. This development is relevant to the design of flat plate solar collectors, for grain drying applications.

scholarly journals Finite element analysis of a solar collector plate using two plate geometries

2016 ◽  
Vol 36 (3) ◽  
pp. 95
Author(s):  
Diego Manuel Medina Carril ◽  
José Gonzalo Carrillo Baeza ◽  
Ruben Dominguez Maldonado ◽  
Francis Aviles Cetina
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Thermal Behavior ◽  
Solar Collector ◽  
Unit Area ◽  
Plate Thickness ◽  
Absorber Plate ◽  
Element Analysis ◽  
Collector Plate ◽  
Rectangular Profile

The thermal behavior of an absorber plate in a solar collector is investigated using finite element analysis. The thermal behavior and efficiency of two absorber plate geometries are studied, using a typical solar collector with a rectangular profile as reference, and a proposed absorber plate with curved geometry. An analysis of the most important parameters involved in the design of the absorber plate was carried out, indicating that the curved geometry of the absorber plate yields an average efficiency ~25% higher than the conventional rectangular geometry. The results suggest that a curved profile made of materials such as aluminum with thermal conductivity higher than 200W/m°C, plate thickness of the order of 2-3mm and with a large density of tubes per unit area of the collector´s plate greatly benefits the thermal efficiency of the solar collector.

scholarly journals Pengaruh Kolektor Pelat Gelombang Dengan Dua Kaca Penutup Terhadap Penambahan Panas Untuk Meningkatkan Kinerja Solar Water Heater

2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Dian Kusuma ◽  
Mustafa Mustafa ◽  
Sudarno Sudarno
Keyword(s):  
Solar Radiation ◽  
Solar Collector ◽  
Solar Water Heater ◽  
Absorber Plate ◽  
Water Heater ◽  
Cover Glass ◽  
Average Heat ◽  
Solar Water ◽  
C 50 ◽  
Initial Heat

The worked principle of solar collector wave absorber plate was to transfer solar radiation to the worked fluid. The solar radiation that falls on the first glass was partially reflected, then on the second glass partially absorbed by the absorbent plate. The heat absorbed by the absorbent plate will be used to heat the worked fluid (water) between the absorbent plate and the storage plate. The purpose of this research was to design and make solar collector used wave plate with two cover glass. The addition of incomed water heat used temperatures of 30 ° C, 40 ° C, 50 ° C. The method used was used an expriment by analyzed the effect of initial heat addition on efficiency. From the results of test data obtained collector performance of solar water heater the greater the addition of heat used then the smaller the efficiency. Each of the average heat additions efficiency at 30 ° C was 19.66%, the temperature of 40 ° C was 17.75%, and the temperature of 50 ° C was 12.23%.

Two-Dimensional Mathematical Model of Evacuated Tubular Solar Collector

1984 ◽  
Vol 106 (3) ◽  
pp. 341-346 ◽  
Author(s):  
F. Rahman ◽  
A. S. Al-Zakri ◽  
M. A. A. Rahman
Keyword(s):  
Solar Collector ◽  
Meteorological Data ◽  
Performance Model ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Absorber Plate ◽  
Collector Plate ◽  
Optical Effects ◽  
Performance Curves ◽  
Energy Balances

Analysis of an evacuated tubular solar collector is presented by developing a two-dimensional performance model. The collector uses a thin flat plate spanning its diameter as its absorbing surface. Energy balances are made on collector plate and tube, each considered as a separate unit. It has been found that a zero capacitance model is quite adequate when hourly meteorological data are used, and hence in this study steady state analysis of the collector is made [1]. The overall loss coefficient has been assumed to be constant for the whole plate. The model also includes optical effects. The emphasis of the investigation is to study the two-dimensional effects in the absorber plate housed in evacuated glass cylinders. Performance curves obtained from the two-dimensional model has been compared with that of HW model. It was found that the HW model overestimates the performance.

Experimental and Theoretical Investigation of Performance of a Solar Chimney Model, Part I: Experimental Investigation

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Essaied M Shuia ◽  
Bashir H Arebi ◽  
Ibrahim A abuashe
Keyword(s):  
Experimental Data ◽  
Wind Speed ◽  
Solar Radiation ◽  
Air Temperature ◽  
Solar Collector ◽  
Experimental Results ◽  
Internal Diameter ◽  
Solar Chimney ◽  
Air Velocity ◽  
Collector Temperature

This paper presents the experimental data that was collected from small pilot solar chimney. The experimental data together with ambient conditions are used to evaluate the performance and study the behavior of the solar chimney; this data will be used for comparison with theoretical models in another paper [part II). The solar chimney prototype was designed and constructed at the Subrata Faculty of Engineering-Libya. The data were collected over several days of June 2011. The solar chimney system contains two main components; the solar collector and the solar chimney. The solar collector root‘ has a circular area of126 m3, the solar chimney is a PVC tube with internal diameter of 0.2 m and the total height of chimney is 9.3 m. The measurements include the intensity of solar radiation inside/outside the collector, temperature and velocity of air at the entrance of the chimney, temperature and speed of wind outside the collector, temperature of the ground inside collector al1d temperature measurements of air at speci?c points at different levels throughout the collector. Solar irradiance was found to affect the chimney temperature and subsequently affects chimney air velocity. The experimental results showed that temperature differences of (30 - 45°C) were recorded between the ambient temperature and that of air inside the chimney in the middle of the day, where the highest air temperature of 73.4°C was recorded at the entrance of the solar chimney. The maximum air velocity of 3.6 m/s was recorded inside the solar chimney at noon on 9 June. Wind speed outside the collector had a small effect on the speed of the air inside the chimney and tends to change slightly, hence, can neglect influence of wind speed on the performance of the system. Also the experimental results indicate that such type of system can trap a suf?cient amount of solar radiation, which elevates the air temperature to a suf?cient value able to generate enough air ?ow to operate a wind turbine to produce electricity; this means the solar chimney system for electricity production can work in the north-western part of Libya in the summer time at least.

Maximisation and Optimisation of the Total Solar Radiation Reaching the Solar Collector Surfaces

2015 ◽  
pp. 873-886 ◽  
Author(s):  
Kacem Gairaa ◽  
Abdallah Khellaf ◽  
Farouk Chellali ◽  
Said Benkaciali ◽  
Yahia Bakelli ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Solar Collector ◽  
Total Solar Radiation

On the measurement of bond conductance in solar collector absorber plate

2008 ◽  
Vol 49 (11) ◽  
pp. 3305-3310 ◽  
Author(s):  
Ali A. Badran ◽  
Mohammed F. Mustafa ◽  
Walid K. Dawood ◽  
Zaid K. Ghazzawi
Keyword(s):  
Solar Collector ◽  
Absorber Plate

Experiment on Flow Boiling Heat Transfer in Tube and Study of Performance of a Vacuum Solar Collector

2007 ◽  
Author(s):  
Shigeki Hirasawa ◽  
Masahiro Taniguchi ◽  
Shunsaku Nakauchi ◽  
Tadayoshi Tanaka
Keyword(s):  
Heat Transfer ◽  
Flow Rate ◽  
Boiling Heat Transfer ◽  
Solar Collector ◽  
Flow Boiling ◽  
Saturation Temperature ◽  
Collector Plate ◽  
Flow Boiling Heat Transfer ◽  
Boiling Heat Transfer Coefficient ◽  
Inclined Angle

A high-vacuum solar collector system with flow boiling in tube has high collector efficiency of solar energy. In this paper flow boiling heat transfer coefficient in tube was measured by changing mass flow rate (30–80 kg/m2s), heat flux (5–30 kW/m2) and inclined angle of collector plate. Inside diameter of tube is 4.4 mm, and saturation temperature is 100°C. Flow boiling heat transfer coefficient is about 8000 W/m2K and decreases at low flow rate. Effect of the inclined angle of collector plate is small. Experimental results of boiling heat transfer coefficients are similar to Sani’s correlation equation. The collector efficiency of vacuum solar collector systems with flow boiling in tube is analyzed and the efficiency is 69% at a standard calculation condition. There is 50°C temperature difference in the collector plate. Effects of the mass flow rate and the vacuum pressure on the efficiency are large. The efficiency decreases at high saturation temperature and at low solar radiation.

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