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Pure drinking water sources are continuously decreasing day by day in the world and in contrast requirement is continuously increasing. Solar still is a device, which converts the saline water into pure form at a lower cost and is useful in the remote areas. But its less productivity and low efficiency is a significant issue to use it as potable water provider. Solar still productivity can be increased by using flat plate collectors, fins, evacuated tubes, different absorbing, and nanomaterials, but the major problem on its productivity is heat loss from glass cover to the ambient. Condenser reduces the temperature of the water vapor and maintain the condensation to enhance the productivity. This review shows different modification in the design of condenser attached with solar still to enhance the yield. At last the future work on the condenser is also discussed here. [ABSTRACT FROM AUTHOR]

In the present work, a new thermosyphon active solar still is presented and experimentally investigated. To propose a simple and reliable alternative for remote regions, evacuated tube solar collectors were used to adsorb solar energy, and an enhanced condenser was employed to increase the rate of distillate production. Taking advantage of a special design, in addition to the collector, water could be poured into the basin and/or condenser. Accordingly, four possible conditions of performance were studied in this work; BECE: empty basin empty condenser, BFCE: filled basin empty condenser, BECF: empty basin filled condenser, BFCF: filled basin filled condenser. Analysis of the results showed the BECE, BFCE, BECF and BFCF cases produced 10.22, 11.86, 15.25 and 16.98 kg/(m2. day) of distillate, respectively. Consequently, it was concluded that filling the condenser effectively decreased the condenser temperature (increased temperature difference between basin and condenser), and caused 46% increase of distillate production. However, filling the basin (increasing evaporation area) enhanced the distillate production by only 14%. In overall, filling both of the basin and condenser simultaneously increased distillate production around 66%. In addition, it was revealed that the efficiencies of BECE, BFCE, BECF and BFCF cases, were 28.2, 34.7, 43.9 and 49.9%, respectively. Image 1 • A new thermosyphon active solar still was presented and investigated. • Enhanced condenser increased distillate production by 46%. • Increasing evaporation surface increased distillate production by 14%. • Production of optimized device increased 66% and reached 16.98 kg/(m2. day). • The temperature of enhanced condenser was around ambient temperature. [ABSTRACT FROM AUTHOR]

Summary: In terms of reducing the environmental pollution caused by effluent water from typical condensers and the water dependency of small modular reactors, indirect dry air‐cooled condensers (IDACs) are being considered an ultimate heat sink. While the performance of air‐cooled heat exchangers has been investigated thoroughly for decades, evaluations of the condenser performance rely primarily on empirical data. Thus, a method for precisely determining the performance of the IDAC under various environmental and thermal‐hydraulic conditions has not yet been understood. The objective of this study is to experimentally investigate the critical parameter that initiates the deterioration of the condenser performance by varying the cooling duty and water velocity. The investigation is also extended to a parametric study of the air‐cooling conditions using a best‐estimate thermal hydraulic analysis code called multi‐dimensional analysis of reactor safety (MARS‐KS) to suggest a method for designing an IDAC system. Results showed that, for a given cooling duty and water velocity, the condenser exhibited an insufficient performance above a certain cooling water temperature. The temperature was defined as the pressure transition temperature (PTT) that initiates the increase in pressure inside the condenser. The calculation results of MARS‐KS were analysed based on the PTT and was used to suggest methods for designing an appropriate IDAC for the cooling duty and environmental conditions of given target site. [ABSTRACT FROM AUTHOR]

This paper presents an experimental work to study the effect of the condenser and the medium of saline water types on the performance of the solar still. Single slope solar still facing the south is used in this work. Also, four types of the condenser are tested: (i) glass, (ii) aluminum plate, (iii) aluminum heat sink with pin fins, and (iv) aluminum plate covered with an umbrella. Moreover, four mediums of the saline water inside the basin are examined: (i) only saline water in the basin, (II) Layers of black steel fibers in the basin, (iii) saturated sand with saline water, and (iv) mixture of sand and black steel fibers saturated with saline water. The solar still of only glass walls and only saline water in the basin is taken as a reference case. The performance of the other cases is referred to the reference case. The results indicate that using heat sink condenser increases the temperature of the saline water. Also, it increases the temperature difference between the condenser and the saline water relative to using glass condenser. Also, using a glass condenser with black steel fibers inside the water basin increases the daily productivity of freshwater by 35%. Using the heat sink condenser increases the daily productivity from 31% in the case of using only saline water to 52% in the case of using black steel fibers in the basin. Using an umbrella of 20 cm wide at the top of the aluminum plate condenser decreases the daily productivity by 26%. Increasing the umbrella wide to 40 cm decreases the daily productivity by 31%. [ABSTRACT FROM AUTHOR]

This work presents a modified solar still with pin fins absorber and external condenser. An experimental comparative study is carried out between the modified solar still with pin fins absorber and condenser, still with pin fins absorber and conventional still. This experimental study is conducted to evaluate the thermal behavior (evolutions of absorber and glass temperatures) and the water production performance of the modified solar still with pin fins absorber and condenser compared to other designs. All experiments are carried out under the meteorological conditions of the region of Gafsa-Tunisia during the days 01/26/2016, 01/27/2016 and 01/29/2016. Experimental results are presented, quantified and discussed to show the utility of the proposed modified solar still. [ABSTRACT FROM AUTHOR]

Access to potable water to the people is narrowing down day after day all over the world. Most of the human diseases are caused by polluted or non-purified water resources. Water purification without affecting the ecosystem is the necessity of the hour. Solar distillation is one of the water purification techniques producing ultrapure distilled water. Solar still distillation systems offer sustainable tools for freshwater production. Numerous environmental and operational parameters attribute to optimize the still design. Different designs were tested by researchers to improve the productivity of solar still. In their experimentations, the solar still integrated with external or internal condenser is deemed to be effective and efficient design. In this detailed survey, we are seeking to introduce, explain and discuss the status of different solar stills integrated with different condensers arrangements. [ABSTRACT FROM AUTHOR]

This paper tackles an optimization approach in order to boost the fresh water production of a new design of a solar still which is located at Sfax engineering national school in Tunisia. This optimization approach is based upon the above mentioned design's improvement by coupling the conventional solar still into at a condenser, solar air and water collector and humidifier. This new concept of a distiller solar still using humidification- dehumidification processes (HD) is exploited for the desalination purpose. As a result of this work, the humidification- dehumidification processes have an essential effect in improving the solar still performance. Performance has been predicted theoretically in terms of water and inner glass cover temperatures, the inlet temperature of air and water of the new concept of distiller on water condensation rate and fresh water production. A general model based on heat and mass transfers in each component of the unit has been developed in steady dynamic regime. The developed model is used, simulating the HD system, to investigate the influence of the meteorological and operating parameters on the system productivity. The obtained set of ordinary differential equations has been converted to a set of algebraic system of equations by the functional approximation method of orthogonal collocation. The developed model is used to simulate the HD system in order to investigate the steady state behavior of each component of the unit and the entire system exposed to a variation of the entrance parameters and meteorological conditions. The obtained results were compared with those of other studies and the comparison gives a good validity of the present results. [ABSTRACT FROM AUTHOR]