Efficiency Of Flat Plate Solar Collector Research Articles

Thermal performance of solar flat plate collector using energy storage phase change materials

AbstractThe present study has been carried out to improve the overall efficiency of a conventional flat plate solar collector (FPSC) using two different heat storage phase change materials (PCMs). Two grades of paraffin wax—Paraffin‐P116 (PCM‐1) and Paraffin‐5838 (PCM‐2) as PCM are selected for the analysis based on their high heat fusion rate, low thermal conductivity, and suitable phase transition temperature. The present code has been validated with experimental results and it showed a maximum error of 6.43% in predicting the water outlet temperature. Absorber plate temperature, useful heat transfer rate, water outlet temperature and efficiencies are estimated to improve the performance of FPSC with and without PCM for various flow rates (15 lph and 30 lph) with two different weights of PCM (9 kg and 14 kg) for three different locations in India, [Chennai (13.0827° N, 80.2707° E), Bengaluru (12.9716° N, 77.5946° E), and Delhi (28.7041° N, 77.1025° E)]. The maximum increment in the efficiency of FPSC with the use of PCM‐1 is 19.59% and with the use of PCM‐2 is 16.53%. Using 14 kg of PCM‐1 with the conventional FPSC at water inlet flow rate of 15 lph increases the overall thermal efficiency up to 19.59% compared with conventional FPSC. The maximum increase in the percentage of efficiency with PCM‐1 from conventional FPSC for different cases of 15 lph‐09 kg is 16.34%, 15 lph‐14 kg is 19.59%, 30 lph‐09 kg is 14.57% and 30 lph‐14 kg is 18.45%. From the present study, it can be concluded that the overall efficiency of FPSC is increased with the use of 14 kg of PCM‐1 with conventional FPSC at the inlet water flow rate of 15 lph.

Experimental Study and Exergy Analysis About the Flat Plate Solar Collector

The increase of clean energy requirement is still enhanced in order to reduce the effect of the global warming therefore, the augmentation of solar energy applications like the solar collectors is attended. The presentstudy of the Flat Plate Solar Collector (FPSC) is performed during the three days’ time (2,3 and 4 of June). Where, the testing time is specified from 09:00Am up to 03:00Pm in order to give more obvious data. Moreover, the energy and exergy analysis equations are utilized to study the 1st and 2nd law of thermodynamics and to provide more appropriate results about the performance of the FPSC. The conducted results show an enhancement in the FPSC efficiency with respect to the increase of the solar irradiance where the last one was explained through one-day time. Furthermore, the FBSC exergy and energy efficiencies conduct the same behaviors during the daytime due to the effect of the solar radiation. In addition, the useful exergy and the exergy efficiency are raised with the progression of time until it reaches approximately midday and then dropped down because of the solar radiation reduction.

On the Correlation between the Geometrical Features and Thermal Efficiency of Flat-Plate Solar Collectors

This article presents the results of numerical and experimental studies on the impacts of the selected geometrical features of liquid solar collectors on their thermal efficiency. The experiments were carried out while meeting the requirements of the ISO 9806:2017 standard. Selected changes in the geometrical features were analysed by using fully functional prototypes of modified solar collectors. The correlations between the design and performance properties of the solar collectors were determined in accordance with the changes in the shape of the thermal efficiency η(T*m) curve.

Improving the Performance of A Flat Plate Solar Collector Using Nanofluid as Working Fluid

Solar energy is the best alternative to limited fossil fuels. The foremost important means of utilizing solar energy are solar collectors. The most common types of solar collectors are flat plate solar collectors. A great deal of theoretical research has been conducted to enhance the flat plate solar collector efficiency. One effective way to increase the efficiency is by using an improved thermal properties fluid as nanofluid. In this paper, a numerical study has been made to enhance the efficiency and improve the performance of solar collector via the use of (Multi-Wall Carbon Nano Tube-water) MWCNT-H2O nanofluid instead of traditional fluid like water as working fluid under the weather of Mosul city / Iraq (36.3489° N, 43.1577° E). One dimensional dynamic model using implicit finite difference method was used. Solving energy conservation equations through the various layers of the solar system is the basis upon which the current model was based. Effects of nanoparticle volume fraction and mass flow rate on the working fluid stream temperature differences, and the thermal efficiency were studied. The mass flow rate was varied from 0.004 kg/s to 0.03 kg/s, while the volume fraction was varied from 0% to 6%. The results of "Nanofluid Based Flat Plate Solar Collector" were compared with the experimental results presented by [1]. The comparison established a good match between the current results and experimental results. The results showed an increase in the working fluid outlet and inlet temperature difference and collector thermal efficiency due to the addition of MWCNT nanoparticles. The temperature difference of "Nanofluid Based Flat Plate Solar Collector" was found 28.8⁰C at 0.014 kg/s and 6% in April, while it was 25 ⁰C at the same condition in the "Water Based Flat Plate Solar Collector case". Also, the thermal efficiency of "Nanofluid Based Flat Plate Solar Collector" was found 2.41% to 6.68% more than the "Water Based Flat Plate Solar Collector case".

“Performance comparison of innovative spiral shaped solar collector design with conventional flat plate solar collector”

Flat plate solar collector is an essential device, which facilitate direct application of solar energy for water heating in household and industrial sector. Existing Flat plate solar collectors (FPSC) suffers from stagnant and comparatively low efficiency. Further research to improve efficiency of FPSC by inculcating innovative design is necessary. To fill the gap, the presented work is an experimental investigation of an innovative design and fabrication approach which deals with analysis of flat plate solar collector efficiency. Design modifications of solar collector always offer an important alternative to achieve significant effect on thermal efficiency. In this work single spiral shaped collector tube as compare to number of riser tubes connected with headers in conventional type flat plate solar collector has been developed. Keeping all other parameters similar to conventional design, it has been observed very encouraging outcomes in efficiencies of solar collector. Under forced mode of testing, enhancement in thermal efficiency achieved is, 21.94% compared to conventional flat plate collector design. Enhancement in exergy efficiency is 6.73%. Overall material saving is about ∼30% and cost of manufacturing and maintenance can be significantly reduced at equivalent performance of conventional collector.

Flow and heat transfer analysis of TiO2/water nanofluid in a ribbed flat-plate solar collector

Abstract The present paper investigates the turbulent forced convection of TiO2/water nanofluid through a ribbed flat-plate solar collector numerically. A three-dimensional simulation of solid flat-plate with flow through the plain and ribbed duct has been performed. The scale-adaptive-simulation approach has been employed to simulate the flow turbulence. The velocity and temperature profiles, Nusselt number and the efficiency of solar flat-plate solar collector have been studied by using plain and ribbed ducts at different Reynolds number and nanoparticles volume fraction. Results indicate that wake circulation region in the back of the rib is intensified at higher Reynolds number leading to an enhancement in the convective heat transfer. Moreover, the efficiency of flat-plate solar collector increases with the nanoparticles volume fraction whilst an enhancement in the efficiency of the ribbed duct is approximately 10% higher than that of the plain duct. This enhancement varies for different nanofluids such that the CuO/water nanofluid provides a higher thermal efficiency than that of TiO2/water.

Effect of Glazing Materials on the Performance of Solar Flat Plate Collectors for Water Heating Applications

The influence of design factors and ambient conditions on the efficiency of flat-plate solar collector is explored in the present study. Being an intensively used equipment for harnessing solar energy, the usage of solar collector has gained momentum due to the depletion of conventional energy resources. The motive of the present work is to enhance the performance of solar collector. Further, the influence of various factors, such as solar irradiance, overall heat loss coefficient, heat removal factor and ambient temperature on the efficiency is presented. These studies would aid in optimization of the solar collector for attaining maximum efficiency.

Experimental investigation of flat plate solar collector using CeO2-water nanofluid

Using nanofluids in thermal energy devices, such as flat-plate solar collectors, is gradually making progress, and getting awareness in the scientific community. Experiments were performed to study the effect of using CeO2-water on the efficiency of flat-plate solar collector by three different volume fractions of CeO2 nanoparticles of 0.0167%, 0.0333% and 0.0666%, while the mean particle dimension was kept constant at 25 nm. An ultrasonic process was used for maintaining the stability of the CO2-water nanofluid. The working fluid mass flux rates were 0.015, 0.018 and 0.019 kg/s m2. The experiments were carried out in Budapest, Hungary on the latitude of 47°28′N and longitude of 19°03′E. Higher collector efficiency was achieved when using CeO2-water nanofluid compared to results achieved with water application. Based on present data, the efficiency of the collector is directly proportional with the mass flux rate and with the volume fraction in the ranges of the present study. Experiments indicate that the highest rise in efficiency of the collector at zero value of [(Ti – Ta)/GT] is 10.74%, for volume fraction (φ) 0.066%, and for mass flux rate of 0.019 kg/s m2 compared to water.

Predicting efficiency of flat-plate solar collector using a fuzzy inference system

With the increasing world population, industrialization and comfort need of humans, energy usage is growing considerably. Nowadays most of the energy needs are obtained from fossil stratum, and hydroelectric or nuclear power plants. However, usage of these fuels has two important problems: (1) These fuels may not exist in the near future and (2) Extensive use of these fuels causes serious environmental pollution. Alternatively, solar energy that is renewable and environmentally friendly energy can be utilized. In design of such renewable energy systems, efficiency is crucial including solar water heating systems. Experiments were conducted to evaluate a flat-plate solar collector performance of thermosiphon solar water heating system during the summer season in Nicosia, North Cyprus. A fuzzy inference system was developed to predict the efficiency of the solar collector. In our fuzzy inference system, we only utilize ambiance temperature, input and output temperature of the solar heating system. The predicted values were found to be in close agreement with the experimental counterparts with 0.9469,3.13, 6.96 coefficient of determination, root mean square error and average forecasting error respectively. It was noted that the proposed fuzzy inference system can provide high accuracy and reliability for predicting the performance of a solar collector. The advantages of this approach as compared to the testing methods are speed, simplicity, and the use of expert knowledge for prediction. Hence, the soft computing approach can be a potential tool for predicting efficiency of a flat-plate solar collector.

Influence of nanofluids on the efficiency of Flat-Plate Solar Collectors (FPSC)

A numerical investigation is performed using finite volume method to study the laminar heat transfer in a three-dimensional flat-plate solar collector using different nanofluids as working fluids. Three nanofluids with different types of nanoparticles (Ag, MWCNT and Al 2 O 3 dispersed in water) with 1–2 wt% volume fractions are analyzed. A constant heat flux, equivalent to solar radiation absorbed by the collector, is applied at the top surface of the absorber plate. In this study, several parameters including boundary conditions (different volume flow rates, different fluid inlet temperatures and different solar irradiance at Skudai, Malaysia), different types of nanoparticles, and different solar collector tilt angles are investigated to identify their effects on the heat transfer performance of FPSC. The numerical results reveal that the three types of nanofluid enhance the thermal performance of solar collector compared to pure water and FPSC with Ag nanofluid has the best thermal performance enhancement. For all the cases, the collector efficiency increased with the increase of volume flow rate while fluid outlet temperature decreased. It is found that FPSC with tilt angle of 10° and fluid inlet temperature of 301.15 K has the best thermal performance.

DETERMINATION OF THE DUST AND SHADING EFFECT ON THE OPTICAL AND ENERGY CHARACTERISTICS OF THE FLAT-PLATE SOLAR COLLECTOR WITH TWO GLASS TRANSPARENT COVERS

The paper presents the results of the calculation of optical and energy parameters of the flat-plate solar collector (FSC) with two glass transparent covers. The author of this paper carried out the calculations taking into account a number of structural and optical parameters of the FSC for the worst weather conditions observed in the 15 January 2014. Firstly, the angles of refraction of sunlight were found considering the diurnal variation of the angle of incidence of sunlight on the surface of the FSC. Secondly, it were defined the reflectance of interfaces, transmittance of a transparent coating of FSC taking into account only the reflectance, and only the absorbability, and, lastly, total transmittance. The paper identifies the reflectance, transmittance and absorbability, as well as hourly and daily averages of FSC efficiency with and without the influence of dust and shading on transparent cover. It was found that the cumulative effect of virtually dust and shading coefficients on the optical and thermal power settings FSC does not exceed 5 ÷ 6% and radiation efficiency varies in the range of 57 ÷ 143 W / m 2 under the conditions of the Absheron Peninsula, in normal service.

Experimental investigation on the efficiency of flat-plate solar collectors with nanofluids

In this study, Cu–H2O nanofluids with different mass fraction and size were prepared through two-step method. Its thermal conductivities and the effect of Cu–H2O nanofluids on the efficiency of a flat-plate solar collector was investigated experimentally. Meanwhile, the water temperature, heat gain of the flat-plate solar water heater and the frictional resistance coefficient of working fluid were also investigated. The mass flow rate of medium was 140 L/h. The experimental results show that the thermal conductivities can be enhanced observably. The efficiency of solar collector was enhanced by 23.83% with using Cu–H2O nanofluids (25 nm, 0.1 wt%) as the absorbing medium. The efficiency of Cu–H2O nanofluids (25 nm, 0.2 wt%) is lower than that of Cu–H2O nanofluids (25 nm, 0.1 wt%). With the nanoparticle size increasing, the efficiency of solar collector decreased. The highest temperature and highest heat gain of water in the nanofluid (25 nm, 0.1 wt%) tank can be increased up to 12.24% and 24.52% compared with water tank, respectively. The increment rate of the frictional resistance coefficient is less than 1% in the whole working temperature area. From the results, it can be indicated that the Cu–H2O nanofluids is suitable for enhancing the efficiency of flat-plate solar collector.

An experimental study on the effect of Cu-synthesized/EG nanofluid on the efficiency of flat-plate solar collectors

An experimental study performed to investigate the effect of Cu nanoparticle on the efficiency of a flat-plate solar collector. The weight fractions of the nanoparticles tested in this study having average diameter of 10 nm, were 0.2% and 0.3% of the nanofluid. A one-step method was used to prepare copper nanofluid from reduction of CuSO4·5H2O with NaH2PO2·H2O in ethylene glycol as the solvent. The experiments were performed in different volume flow rates of the nanofluid from 0.016 to 0.050 kg/s and the standard of ASHRAE 93 was used to test the solar collector's performance. It was found that by increasing the nanoparticle weight fraction, the efficiency of the collector was improved. Also, the lowest removed energy parameter could be reached by using 0.3 wt% Cu/EG nanofluid at 1.5 Lit/min and the highest absorbed energy parameter was achieved under the same conditions.

A Mathematical Model of Indirect Solar Drying of Dairy Products (Jameed)

A Mathematical modeling of indirect natural convection solar dryer was designed for drying one of the famous dairy product in Jordan called Jameed. The intended solar dryer system is environmentally friendly and consumes zero electricity. The dryer consists of a flat plate solar collector having dimensions of 0.1 m height, 0.8 m width and 1.2 m length. A drying chamber consisting of four trays separated equally from each others at a distance of 0.2 m. The chamber is 1 m long made of wood. Each tray has a cross section of 0.8 m x 0.4 m. The solar collector is studied separately to establish the effect of changing its width or length on the air outlet temperature and mass flow rate. The drying chamber is used to dry 4 kilograms of jameed, each 1 kilogram is distributed on each tray. The total solar irradiation on the collector surface and chamber walls at each hour of the day was also calculated at the 21 st of May in Jordan. At these specific solar irradiation, the flat plate solar collector efficiency was almost constant having an average efficiency of 37% and a maximum outlet temperature of 41 °C at 1p.m. The drying time for trays 1, 2, 3 and 4 were 16.4, 19.14, 22.6 and 25.71 hours, respectively.

Performance Analysis of a Solar Collector Using Nanofluids

The Efficiency of Energy and Exergy is Generally Used as the Mostimportant Parameter in Order to Introduce and Compare the Thermal Systems Offlat Plate Solar Collectors. the First Law of Thermodynamics is Not Solelycapable of Demonstrating Quantitative and Qualitative Performance of Suchsystems, so the Second Law is Required to Illustrate the Performances. in Thispaper, an Analysis was Done for Heat Transfer Performance and Exergy Efficiencyof Flat Plate Solar Collectors Using Four Types of Nanofluids, e.g. Zno/water,CeO2/water, Nio and Coo/water. these Nanofluids were Used Withdifferent Nanoparticle Volume Fractions in the Range of 1% to 4%. Besides this,the Present Work also Focuses on the Performance of Solar Collector Withdifferent Volume Flow Rates. Investigation Consequences are also Compared Withthe Presently Available Literature for Conventional Solar Collectors. Thehighest Heat Transfer Performance and Exergy Efficiency were Obtained for CeO2/waternanofluid among all Nanofluids. Nio/water and Coo/water Nanofluids Representalmost same Performance but Higher than Water. the Results Reveal that, CeO2/waternanofluid Indicates Maximum Heat Transfer with Maximum Exergy.

An experimental investigation on the effect of MWCNT-H2O nanofluid on the efficiency of flat-plate solar collectors

In this study the effect of MWCNT nanofluid, as absorbing medium, on the efficiency of a flat-plate solar collector was investigated experimentally. The weight fraction of CNTs was 0.2% and 0.4%. The effect of Triton X-100 as a surfactant on the stability of nanofluid was studied. The tests were performed in different mass flow rates of nanofluid from 0.0167 to 0.05kg/s. ASHRAE standard was used to perform the tests. Results show that by increasing the weight fraction from 0.2% to 0.4%, there is a substantial increase in the efficiency. Also, using the surfactant causes an increase in the efficiency.

An experimental investigation on the effect of Al 2O 3–H 2O nanofluid on the efficiency of flat-plate solar collectors

In the present work the effect of Al 2O 3–water nanofluid, as working fluid, on the efficiency of a flat-plate solar collector was investigated experimentally. The weight fraction of nanoparticles was 0.2% and 0.4% and the particles dimension was 15 nm. Experiments were performed with and without Triton X-100 as surfactant. The mass flow rate of nanofluid varied from 1 to 3 Lit/min. The ASHRAE standard was used to calculate the efficiency. The results show that, in comparison with water as absorption medium using the nanofluids as working fluid increase the efficiency. For 0.2 wt% the increased efficiency was 28.3%. From the results it can be concluded that the surfactant causes an enhancement in heat transfer.

Determination of efficiency of flat-plate solar collectors using neural network approach

In this study, a new formula based on artificial neural network (ANN) technique was developed to determine the efficiency of flat-plate solar collectors. In practice, the ANN model can be used for modeling the efficiency of solar collectors with complex structures when other models may have difficulties. Logistic sigmoid transfer function was used in the network. Meteorological data of summer session (from July to September) for Ankara were used as training data in order to train the neural network. Surface temperature in collector, date, time, solar radiation, declination angle, azimuth angle and tilt angle are used in the input layer of the network. The efficiency of flat-plate solar collector is in the output layer. The results show that the maximum and minimum deviations were found 2.558484 and 0.001969, respectively. The advantages of ANN model compared to the conventional testing methods are speed, simplicity, and the capacity of the ANN to learn from examples.

Effect of contact spacing on efficiency of flat-plate solar collectors

The attachment of an extended surface to an energy removal tube in a noncontinuous manner is considered. Rather than to provide continuous weld or solder to form thermal contact, the use of a uniform distribution of finite regions of contact is examined. In particular, the application to solar energy collection is considered where a discrete, discontinuous system of contacts offers potential economic benefit in the fabrication and reliability aspects of construction. The problem is formulated mathematically in nondimensiona l terms and numerical solutions employing the finite element method are obtained. Specifically, the sensitivity of the thermal performance of the collector system to weld/solder joint dimensions is presented. It is found that the discontinuous nature of the weld can significantly degrade system performance with the degree of degradation strongly dependent on the fin surface Biot modulus. Further, it is observed that the controlling parameter with respect to the weld dimensions is the perimeter length of the weld location of contact. This observation will permit direct application of the results obtained to situations other than the rectangular weld planform specifically considered. A novel and useful method of representatio n, in the form of a relative performance ratio, is also introduced and should prove useful in future two-dimensional fin analyses.

Daily efficiency of solar collectors

It is shown that the daily efficiency of flat-plate solar collectors working at constant flow rate can be evaluated with a simple algorithm when their structural features are known. It is also shown that long-term performances can be calculated starting from monthly values of global radiation.