Search

Solar collectors are thermal equipment that receives solar energy by absorbing sunlight and converting it into thermal energy. The working fluid is the most important part of the system, as nanomaterials were used with water instead of pure water, as this method is one of the best ways to increase the performance of the solar collector. In this study, the performance of the evacuated tube solar collector was improved by designing an electronic curtain made of acrylic mirror, in addition to adding nanoparticles of Al2O3 to a liquid work (water). A volume fraction of nanoparticles of 1%, 3%, and 5% was used at flow rates of (3, 9, 15)L/min. The performance of a vacuum tube solar collector was compared using Al2O3 and water within the stated flow rates. Through the results obtained, it was found that the efficiency of the solar collector increases with the increase in the concentrations of the nanomaterial and the presence of acrylic mirrors on both sides of the evacuated tubes as a reflective surface. [ABSTRACT FROM AUTHOR]

An adaptive artificial neural network model of a fuzzy neural inference system is evaluated in this paper to predict the performance of a nanofluidic evacuated tube solar collector. Variable intake temperatures and weight percentages of the aluminum oxide nanofluid (1 percent, 3 percent, 5 percent), as well as different flow rates (3, 9, 15) l/min were investigated. In this study, three ANFIS inputs were used: inlet temperature, solar radiation rate, and ambient temperature. Where one output is obtained from the artificial neural network, which is the values of the angles of the reflective electronic curtain made of acrylic mirrors, which enhance the performance of the solar collector as well as control the temperature of the solar collector when the curtain is closed. We can note that the practical results are consistent with the prediction results by predicting the performance of the solar collector produced by ANFIS. [ABSTRACT FROM AUTHOR]

In previous studies, an electronic curtain made of one reflective material was used, while in this study, the two electronic curtains made of two various reflective materials were utilized: acrylic mirrors and aluminum foil; this is to compare any electronic curtain of any reflective material that has the ability to reflect more solar radiation and thus increase the temperature of the fluid located inner the tube and thus improve the efficiency of the evacuated tube solar collector clearly. Copper oxide was used and adding it to distilled water as a basic working fluid with a diameter of (50nm) with three flow rates (6,12,18 L/min) and three volumetric concentrations (1%, 3 %, 5 %) to increase the heat gain and thus increasing the efficiency of the collector as well. Reflective electronic curtains were placed over the collector tubes to protect the tubes from weather conditions. The findings showed that the utilize of an electronic curtain made of acrylic mirrors had a more significant impact on the performance of the solar collector compared to the electronic curtain made of aluminum foil, Where the uttermost efficiency of the solar collector was 55% in the case of using an electronic curtain made of acrylic mirrors in the presence of nanofluid copper oxide at a flow rate of 18 L/minute and a volumetric concentration of 5%. While the maximum efficiency of an evacuated tubular solar collector in the case of using an electronic curtain made of aluminum foil was 47.68%, at the same flow rate and volumetric concentration. [ABSTRACT FROM AUTHOR]

This research investigated the impact of the nanoparticles (Cu/DW) on the characteristics of a solar vacuum collector, as Nano fluids are distinguished by their high thermal conductivity. The Cu nanoparticles' diameter was 40 nm, and three distinct volume fractions of 1,3% and 5% vol nanoparticles were investigated at flow rates of 30, 50, and 60L/min. The experiments were done at the city of Baghdad, Iraq, at longitude 44° 14′ East and latitude 33° 33′ North. The results show that a volumetric fraction of 5 vol% nanoparticles at a flow rate of 60 L/min produces the most usable heat gain. The findings recorded that adding other nanoparticles enhanced the thermic efficiency of the evacuated solar tube. Compared to pure water's efficiency and thermal performance, Nano fluid exhibits much higher levels of other. A solar vacuum collector's capacity to boost its heat transfer rate and its thermal efficiency is directly related to the size and kind of nanoparticles utilized in the process. Because of the higher nanoparticle concentration, a larger heat was captured, which may be put to various beneficial uses. Including Cu nanoparticles in the working fluid will increase the temperature of the fluid. The temperature difference between the intake and the output was greater as the volume percentage of copper nanoparticles rose compared to the volume of distilled water. The granular size and its type are important in improving heat transfer. The thermal properties of Nano fluids are better than distilled water, except for the specific heat capacity, because the fluid needs more heat than the Nano fluid. [ABSTRACT FROM AUTHOR]

An experimental study was conducted to analyze the performance of the evacuated tube solar collector by adding aluminum nanoparticles to distilled water as a working fluid with different volumetric concentrations (1%, 3%, 5%) according to the mathematical equations, and different volumetric flow rates, in addition to using a reflective electronic curtain of acrylic mirrors. The performance of the solar collector was compared with the nanofluid ((Al (30 nm)+(Distilled water)) and water with flow rates (3, 9, 15) L/min. The results showed an improvement in the performance of the solar collector by adding the nanofluid ((Al (30 nm)+(Distilled water)) compared with water as the main working fluid in the system with and without the reflective curtain. The maximum efficiency of the solar collector was (48.5%) at a volumetric concentration (5%) at a flow rate (15 L/min) without the reflective curtain. While the maximum efficiency was (60.2%) with the same concentration and flow rate when the reflective curtain was present. The results also showed an increase in the performance of the solar collector by increasing the volumetric concentrations of aluminum nanoparticles and the flow rates. [ABSTRACT FROM AUTHOR]

This article investigated the effect of nanoparticles (Cu/DW) on the thermal performance of a solar vacuum collector, as nanofluids are characterized by high thermic conductivity. The Cu nanoparticles used had a diameter of 30 nm with three different volume fractions of 1,3 and 5% vol nanoparticles examined at different flow rates of 30, 50, and 60 L/min. The tests were conducted in the city of Baghdad, Iraq, at a longitude of 44° 14′ E and latitude of 33° 33′ N. The results presented that the volumetric fraction of 5 vol% nanoparticles at a flow rate of 60 L/min achieves the maximum useful heat gain. The data showed that adding more nanoparticles improved the thermal efficiency of the evacuated solar tube. The improvement results of ETSC at a flow rate of 60 L/min increase to 19.69% for the volume fraction of nanoparticles of 5% vol. In contrast, the improvement rate of distilled water was 4.03% for the same flow assessment. According to the findings, the temperature difference and absorbed energy increased when nanoparticles were used. [ABSTRACT FROM AUTHOR]

In this paper, the improvement of vacuum solar collector efficiency is studied by two methods. The first method is to place a solar reflective curtain in front of the solar vacuum collector that operates on the solar panel system. This curtain increases the amount of reflection of solar radiation back to the vacuum collector. The curtain automatically follows the sun's rays, and the reflectors' movement depends on the nanofluid's temperature. The second method uses the ZrO2 nanofluid with a diameter of 60 nm with distilled water. The experiment used three volume concentrations, 1,3 and 5% by volume, with three flow rates of 30,50, and 60 L/m, respectively. The results showed an improvement of the thermal properties of the solar vacuum collector when using the solar reflective curtain and nano-liquid by 10.76%, while the amount of progress without using the solar reflective curtain was 5. 51%. [ABSTRACT FROM AUTHOR]

Evacuated tube solar collectors are an important part of the solar heating system. This solar energy is absorbed by tubes and converted to heat, where this heat is transported to the water. The current research proposes a way to boost the efficiency of the solar collector using evacuated tubes through the design and construction of an electronic acrylic curtain whose movement is controlled using artificial intelligence to enhance the amount of solar radiation falling on the evacuated tubes. The tilt of an electronic curtain is controlled according to the direction of solar radiation. This electronic curtain works to protect the evacuated tubes in addition to acting as a reflector. Through the results obtained, the solar collector's efficiency improved approximately by 15% compared to solar collectors that operate without a curtain, and therefore the proposed design has a higher thermal performance than other systems. [ABSTRACT FROM AUTHOR]

One of the most widely used solar collectors is a vacuum tube solar collector. Nanofluids were used to improve the heat transfer performance of these collectors because they are characterized by high thermal conductivity. This paper studied the effect of (ZrO2/DW) nanoparticles on the thermal performance of an evacuated solar collector. The ZrO2 nanoparticles used were 60 nm in diameter with three different volume fractions of 1,3 and 5% vol nanoparticles examined at various flow rates of 46, 67, and 93 L/min. Experiments were carried out in Baghdad city of Iraq, at a longitude of 44° 14 ′ E and latitude of 33° 33 ′ N. The results showed that the volume fraction of nanoparticles 5%vol at a flow rate of 93 L/min attain the maximum useful heat gain. The values denoted that adding more nanoparticles enhanced the thermal efficiency of the evacuated solar tube. The thermal enhancement result of ETSC efficiency at a flow rate of 93 L/min is raised to 5.69% for the nanoparticles volume fraction of 5% vol, while the enhancement rate of distilled water was 4.03% for the same flow rate. Findings dedicated that temperature difference and absorbed energy increased when nanoparticles are used. [ABSTRACT FROM AUTHOR]

This paper pursuits to learn about and control of evacuated tube solar collector the usage of Finned Electronic Curtain to enhance performance. The starting of the fins work is to function in accordance to the times listed in the time table and start shifting every 1/2 hour period till it follows the sun. It shall be closed at the time of closure, As for the control, it will become by means of the temperature sensor from the contact eighty. it closes and opens from the return 65 automatically, also, the same programmed algorithm and matlab by programming the Arduino, And it became control, so its work without programs and made a simulation of the Android program, For the phone until they control and give me data about the temperature and the ability to open and close. The improvement percentages of Cu(25nm)+PW) at without fins machine are (12.28%, 20.52% and 25.18%) while the percentages with TiO2(50nm)+PW)are (3.906 percent, 5.34% and 7.407%) due to thermal houses and nanoparticles measurement of first kind greater than 2d kind at distinctive drift fee and concentration. Finally, the charge of enchancment of effectivity share at case of distilled water only is (2.34% and 3.81%). on the other hand the percentages of enhancement of Cu(25nm)+(Al(25nm)+DW) at with shadow gadget are (19.53%, 24.42% and 28.14%) at the sametime as the percentages with TiO2(50nm)+PW)are (7.03%, 9.16% and 11.89%). The results show Finned Electronic Curtain controller is good controlled and a superior performance of evacuated Tube Solar., Finned Electronic Curtain has been applied evacuated tube solar collector in Baghdad. There controller has been extensively utilized in many industrial applications. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the performance of solar Nano fluid heating system by using Al2O3 Nano liquids as working liquid and also the effect of nanoparticles on the solar Nano liquid heating system. To obtain a higher thermal conductivity of the liquid, the efficiency of the solar collector can be improved as compared to that of distilled water. The approach used in this study to improve heat transfer and pressure drop by using spirally coiled tube heat exchange in solar apparatus and Nano fluid instead of base liquid (distilled water).one nanoparticles are used for exploration with different concentrations (i.e. 1, 3 and 5% by volume), the volume flow rate (12, 24, 36 L / min) and the important working fluid used to be distilled water. The effect, of Al2O3 with distilled water as the base fluid on the effectivity of the photo voltaic collector for unique extent glide fees (12, 24, 36 L / min) used to be as soon as investigated.The experimental penalties showed that the attention at (1% volume) tested non-significant effects in contrast to distilled water, whilst the effects indicated that the cocentration of 5% vol has a widespread have an impact on the photo voltaic collector performance. Nano fluid sorts are a predominant difficulty in enhancing heats change and enhancing the vacuum tube overall performance of the photo voltaic collector. A Clear extend in efficiency and thermal obtain used to be observed the use of picture voltaic reflectors can be viewed as a primer for accumulating solar power at some stage in the heating season that can make contributions to image voltaic electrical energy ranging from (40% to 80%(of the total solar radiation incident, due to the fact the reflector concentrates both the diffuse and direct radiation of the sun toward the collector. [ABSTRACT FROM AUTHOR]