Search for: solar-still
Total 24 records
Theoretical and experimental study of cascade solar stills, Article Solar Energy ; Volume 90 , April , 2013 , Pages 205-211 ; 0038092X (ISSN) ; Sharak, A. Z ; Moghadam, H ; Tabrizi, F. F ; Sharif University of Technology
Most part of Iran is dominated by arid and semi-arid areas due to low annual rainfall. The need for production of fresh water from brackish water is considerably high, especially in dry regions. In this study 1 month daily-based experimental data from a solar still site has been reported. The technical and operational problems of this site which finally contributed to the total cease of the site are described. Then a detailed analysis is investigated on progress of a prototype which constructed in order to solve the site's problems. The results of 1 month of experimental data of the final design showed that the last prototype could be used to solve the current problems of the site. The...
A thorough investigation of the effects of water depth on the performance of active solar stills, Article Desalination ; Vol. 347 , 2014 , Pages 77-85 ; ISSN: 00119164 ; Taghvaei, H ; Jafarpur, K ; Karimi Estahbanati, M. R ; Feilizadeh, M ; Feilizadeh, M ; Seddigh Ardekani, A ; Sharif University of Technology
One of the most important operating parameters which affects the performance and efficiency of active solar stills is brine depth. In all of the previous experimental or theoretical studies, effects of water depth were investigated during only the first 24-hour period (or even shorter periods) of the operation of active solar stills. In other words, only the first day was taken into account. However, the production of an active solar still depends on several parameters such as brine temperature at sunrise (initial temperature), which are all affected by the depth variation after the first day of operation. However, the present research experimentally investigates the long-term effects of...
Experimental investigation of the effect of solar collecting area on the performance of active solar stills with different brine depths, Article Desalination ; Volume 358 , 2015 , Pages 76-83 ; 00119164 (ISSN) ; Taghvaei, H ; Jafarpur, K ; Feilizadeh, M ; Karimi Estahbanati, M. R ; Sharif University of Technology
Solar collecting area is one of the most important operating parameters of active solar stills. No experimental work has been performed to investigate the effect of this parameter to date. Furthermore in all of previous theoretical studies the effect of solar collecting area was examined during only the first 24-hour period of the operation of stills with one specified brine depth. However the present work experimentally studies the long-term simultaneous effects of collector area and brine depth on the performance of active solar stills. For this purpose four parallel active solar stills with different collector areas were fabricated and experiments were conducted for 5 consecutive days...
Experimental investigation of a novel passive solar still with additional condensation on sidewalls, Article Desalination and Water Treatment ; Volume 89 , 2017 , Pages 29-35 ; 19443994 (ISSN) ; Favakeh, A ; Faegh, M ; Sadrhosseini, H ; Sharif University of Technology
In common solar stills, a portion of the produced vapor undesirably condenses on the sidewalls and runs down to be mixed with saline water in the basin. This results in lower distillate output of the system. The aim of this study was to improve the condensation process of a solar still without complicating its structure to collect the water condensed on sidewalls. The proposed solar still was made of two containers nested one inside the other such that the smaller container, containing saline water, fitted easily into the larger container. There was a thin gap between the two in which condensed liquid on sidewalls, ran down and was collected from the bottom of the larger container. The...
Experimental investigation of a multi-effect active solar still: The effect of the number of stages, Article Applied Energy ; Volume 137 , 2015 , Pages 46-55 ; 03062619 (ISSN) ; Feilizadeh, M ; Jafarpur, K ; Feilizadeh, M ; Rahimpour, M. R ; Sharif University of Technology
Elsevier Ltd 2015
In this work, the effect of the number of stages on the productivity of a multi-effect active solar still was experimentally investigated for the first time. Moreover, system performances in continuous and non-continuous modes were compared. For this purpose, indoor experiments were conducted on 4 similar solar still devices with different stages (1-4 stages) in order to accurately control the environmental conditions. In addition, water production was hourly measured during the whole 24-h experiment. The results show that with increased number of stages, distillate production can be predicted with a quadratic function. Moreover, adding a maximum of 6 and 10 additional stages can...
A new radiation model for a single-slope solar still, Article Desalination ; Volume 262, Issue 1-3 , 2010 , Pages 166-173 ; 00119164 (ISSN) ; Soltanieh, M ; Jafarpur, K ; Karimi Estahbanati, M. R ; Sharif University of Technology
In this paper, a new radiation model for a single-slope solar still has been developed which for the first time takes into account the effect of all walls of the still on the amount of incident solar radiation on the water surface and each wall. In this model, the walls are projected on the cover to calculate the amount of beam radiation received by any components inside the still. This is in contrary to the previous models in which stills' walls were projected on a horizontal surface and their shadows on the water surface and the walls were either neglected or not computed properly. The predictions of the proposed model are compared with the experimental data obtained in the present work...
Optimization of geometrical dimensions of single-slope basin-type solar stills, Article Desalination ; Volume 424 , 2017 , Pages 159-168 ; 00119164 (ISSN) ; Soltanieh, M ; Karimi Estahbanati, M. R ; Jafarpur, K ; Ashrafmansouri, S. S ; Sharif University of Technology
In the present work, effects of height, length, and width of a single-slope basin-type solar still on its distillate production was investigated. For this purpose, a radiation model was developed which accounts for the influences of all walls on quantities of received solar radiation by the base and saline water of the still. Moreover, in this radiation model, the side walls of the still were considered as the trapezoid and the diffuse as well as beam components of solar irradiance were separately taken into account for the first time. Abilities of the present model were compared with earlier ones. Furthermore, the predictions of the current model were compared with the present experimental...
Productivity enhancement of solar stills by nano-coating of condensing surface, Article Desalination ; Volume 454 , 2019 , Pages 1-9 ; 00119164 (ISSN) ; Soltani Goharrizi, A ; Ayatollahi, S ; Feilizadeh, M ; Sharif University of Technology
Elsevier B.V 2019
Wettability is one of the most important factors which significantly influences solar still efficiency. Moreover, it determines the condensation mode, i.e., filmwise or dropwise condensation. In the present study, materials with different wettability were applied as the condensing surface to evaluate the effect of wettability on the distillate production of a single slope solar still. To compare the effects of dropwise and filmwise condensation on the condensate yield, the wettability of the condensing surface was changed by applying a nano-silicon solution according to a dip coating technique. All the experiments were conducted at three surface inclination angles. The results revealed that...
Experimental Study of Solar Still with Heat Pipes Using Phase Change Material, M.Sc. Thesis Sharif University of Technology ; Sadrhosseini, Hani ; Shafii, Mohammad Behshad
Solar distillation is a comparatively easy treatment of brackish (i.e. contain dissolved salts) water supplies. Distillation is a well-known process, which may be used for water filtration utilizing heating sources. In this research, the solar distillation set with heat-pipes was made and tested in 18 months.At the first step, during four days, the pipes were filled with some water to certain height every day while temperature and produced water were estimated. At the second step, the vacuum pipes were filled with some oil and tested for 4 different heights within 4 days; and in final steps, aluminum chips, washing wire and metal foam were shaded into the tank then tested by an optimum water...
Experimental Investigation of Double Wall Solar Still, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad ; Sadrhosseini, Hani
Salt water is desalinated to produce fresh water suitable for human consumption or irrigation. Most of desalination methods require consuming large amounts of fossil fuels. Solar distillation is one of the best techniques from another available techniques for desalinating in small-scale brackish water. The main problem of these systems is the low rate of water production.Single basin solar still is a very simple solar device used for converting available brackish or waste water into potable water. This device can be fabricated easily with locally available materials. The maintenance is also cheap and no skilled labor is required. It can be a suitable solution to solve drinking water problem....
Latent Heat Energy Vapor Storage in Phase Change Materials in Solar Stills, M.Sc. Thesis Sharif University of Technology ; Rajabi, Abbas ; Shafie, Mohammad Behshad
Providing fresh water, ending fossil fuels, using renewable energy and achieving a clean biological environment in different parts of the world especially in Iran beside having access to many saline water sources, Shows the need for research in the field of solar still desalination. The goal of current study is to increase the performance of the solar still system through the use of an energy storage system and an additional condenser. Adding an additional condenser to a conventional solar still lead to an increase in the rate of evaporation and consequently increase the production of the system. Also, by collecting distilled water from the sidewalls, the amount of water produced...
Effects of amount and mode of input energy on the performance of a multi-stage solar still: An experimental study, Article Desalination ; Volume 375 , 2015 , Pages 108-115 ; 00119164 (ISSN) ; Karimi Estahbanati, M. R ; Ardekani, A. S ; Zakeri, S. M. E ; Jafarpur, K ; Sharif University of Technology
Effects of the amount and mode of input energy to an active multi-stage solar still were investigated in this work. To control the input energy, an electrical heater controlled by a PLC was utilized to simulate the energy absorbed by solar collectors. The study of the amount of input energy indicated that the freshwater production was a quadratic function of the collector over basin area (CBA) ratio. It was also found that stages 1 to 4 produced about 36%, 26%, 20% and 18% of the overall yield, respectively. Moreover, the effect of employing a thermal energy storage (TES) on the system performance was studied by comparing the mode of feeding energy according to the daily solar radiation...
Year-round outdoor experiments on a multi-stage active solar still with different numbers of solar collectors, Article Applied Energy ; Volume 152 , 2015 , Pages 39-46 ; 03062619 (ISSN) ; Karimi Estahbanati, M. R ; Jafarpur, K ; Roostaazad, R ; Feilizadeh, M ; Taghvaei, H ; Sharif University of Technology
Elsevier Ltd 2015
The present work investigated the outdoor performance of a basin type multi-stage solar still as well as the effect of collector over basin area (CBA) ratio on the distillate production. The effect of CBA was studied in outdoor experiments for the first time. The system consisted of a still coupled with one, two or three flat-plate solar collectors. In order to study the effect of CBA more accurately, the experiments were conducted in both winter and summer. In these experiments, the distilled water production of the multi-stage still was measured during the whole 24. h of a day on an hourly basis. The results revealed that in the winter, the basin coupled to one solar collector (CBA. =...
Examination of a novel solar still equipped with evacuated tube collectors and thermoelectric modules, Article Desalination ; Volume 382 , 2016 , Pages 21-27 ; 00119164 (ISSN) ; Shahmohamadi, M ; Faegh, M ; Sadrhosseini, H ; Sharif University of Technology
In this article, a novel solar still which is equipped with thermoelectric modules to utilize the heat of vapor condensation is experimentally investigated. The use of thermoelectric modules as devices for generating electricity from the temperature difference between two environments (hot vapor steam and cold ambient air) as well as taking outstanding advantages of evacuated tubes as collectors with high performances in adverse climatic conditions, led to utilizing of the energy dissipated due to vapor condensation and a considerable increase in the performance of the system. The effect of using the generated electricity to operate a small propeller fan for inducing forced convection was...
Experimental investigation of a solar still equipped with an external heat storage system using phase change materials and heat pipes, Article Desalination ; Volume 409 , 2017 , Pages 128-135 ; 00119164 (ISSN) ; Shafii, M. B ; Sharif University of Technology
Elsevier B.V 2017
In this study, a novel idea of storing the latent heat of condensing vapor in solar stills by means of phase change materials (PCMs) as a thermal storage is experimentally investigated. During the daytime, the generated water vapor by the solar energy, is conducted to an external condenser filled with PCM to be condensed. The wasted latent heat is absorbed by PCM and thereby stored. It is worth noting that there is no direct contact between the saline water and the PCM, therefore, the solar energy is not directly stored in the PCM. In the evening, the energy stored in the PCM is transferred as heat to the saline water by heat pipes and enables the desalination process to continue. Several...
Design and Fabrication of a Solar Still Equipped with Latent Heat Storage System and Heat Pipes, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad
Experimental Investigation of the Performance of Multiple Effect Active Solar Stills, M.Sc. Thesis Sharif University of Technology ; Roostaazad, Reza ; Jafarpur, Khosrow ; Maghsoodi, Vida
Energy and environmental crises force different countries to consider new clean sources of energy, especially renewable energies. Fortunately, Iran is located on the solar belt and has a great potential to utilize this huge source of clean, sustainable, accessible and cheap energy. One of the applications of the solar energy is desalination of salty and polluted waters. In this regard, the performance of Multiple Active Solar Stills is investigated in this research. To do so, four similar samples of this device with one, two, three and four stages, were constructed on which many experiments were conducted for 24 hours periods. Experiments were conducted in both continuous (several days) and...
Design, Manufacture, and Investigation of the Desalination System Using Direct Absorption Solar Collector with Organic Colloids and External Condenser, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad
The use of nanofluids for direct absorption of solar irradiance to produce freshwater has received much attention. Water-based nanofluids include metals, metal oxides, and nanocarbon-based fluids, which increase collector efficiency. On the other hand, the production cost of nanofluids is high, and when discharging the brine after the desalination process, these nanofluids cause environmental issues. Therefore, water-based organic colloids of coffee, walnut shell, black tea, and madder have been studied to overcome these problems. To accurately measure the behavior of colloids, laboratory single slope solar still was used in laboratory conditions. Also, two single slope solar stills with the...
Nano-coated condensation surfaces enhanced the productivity of the single-slope solar still by changing the condensation mechanism, Article Journal of Cleaner Production ; Volume 265 , 2020 ; Soltani Goharrizi, A ; Ayatollahi, S ; Feilizadeh, M ; Sharif University of Technology
Elsevier Ltd 2020
Solar stills are considered an environmentally friendly technique to produce fresh water. The condensation surface plays an essential role in controlling the efficiency of the solar still. This main parameter is critically affected by the wettability of the condensation surface that affects the condensation mechanism, namely drop-wise or film-wise condensation. This study aims to enhance the efficiency of solar stills by altering the surface wettability hence changing the condensation mechanism using nanomaterials. In this experimental work, different condensation surfaces were coated by silicone nanoparticles to change the condensation mechanism from film to dropwise. Scanning electron...
Modeling and Experimental Investigation of a solar Hybrid System to Produce Freshwater from Waste Heat of Photovoltaic Module by Using Thermosyphon heat pipes with different Configurations, M.Sc. Thesis Sharif University of Technology ; Behshad Shafii, Mohammad ; Roshandel, Ramin
With regard to an increasing world population and the constant capacity of water resources, new and valid methods should be implemented to preserve freshwater resources and accordingly produce drinking water. In the present study, a solar hybrid system was studied by experimental and theoretical means to facilitate the transformation of waste heat from photovoltaic module (PV module) into useful heat that can be used in a solar desalination (SD) system for freshwater production purposes. The study aimed to fabricate a SD system by using both PV module and thermosyphon heat pipes (THPs) technologies in a single system. In the modeling section, the goal is to present a comprehensive model...