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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,603 records · Page 89
All sourcesNASA NTRSDOE OSTI
NASA NTRS1970

The role of remotely sensed and relayed data in the Delaware River Basin

A discussion is presented of the planned integration of the existing Delaware River Basin water quality monitoring and data processing systems with a data relay experiment proposed for the Earth Resources Technology Satellite (ERTS)-A, which will be launched in 1972. The experiment is designed to use ERTS-A as a data relay link for a maximum of 20 hydrologic stations in the basin, including streamgaging, reservoir level, ground water level,and water quality monitoring stations. This experiment has the potential for reducing the timelag between data collection and dissemination to less than 12 hours. At present there is a significant timelag between the time when the data are recorded at a monitoring site and the water resources agencies receive the data. The timelag exists because most of these instruments operate in remote locations without telementry, and the data records are removed manually, generally at a weekly frequency. For most water quality monitoring, the data do not reach water resources agencies for a period of 2 weeks to 2 months.

Paulson, R. W.↗
NASA NTRS2013

Advanced Water Purification System for In Situ Resource Utilization

A main goal in the field of In Situ Resource Utilization is to develop technologies that produce oxygen from regolith to provide consumables to an extraterrestrial outpost. The processes developed reduce metal oxides in the regolith to produce water, which is then electrolyzed to produce oxygen. Hydrochloric and hydrofluoric acids are byproducts of the reduction processes, which must be removed to meet electrolysis purity standards. We previously characterized Nation, a highly water selective polymeric proton-exchange membrane, as a filtration material to recover pure water from the contaminated solution. While the membranes successfully removed both acid contaminants, the removal efficiency of and water flow rate through the membranes were not sufficient to produce large volumes of electrolysis-grade water. In the present study, we investigated electrodialysis as a potential acid removal technique. Our studies have shown a rapid and significant reduction in chloride and fluoride concentrations in the feed solution, while generating a relatively small volume of concentrated waste water. Electrodialysis has shown significant promise as the primary separation technique in ISRU water purification processes.

Anthony, Stephen M.↗
NASA NTRS2014

Advanced Water Purification System for In Situ Resource Utilization Project

A main goal in the field of In Situ Resource Utilization is to develop technologies that produce oxygen from regolith to provide consumables to an extratrrestrial outpost. The processes developed reduce metal oxides in the regolith to produce water, which is then electrolyzed to produce oxygen. Hydrochloric and hydrofluoric acids are byproducts of the reduction processes, which must be removed to meet electrolysis purity standards. We previously characterized Nation, a highly water selective polymeric proton-exchange membrane, as a filtrtion material to recover pure water from the contaminated solution. While the membranes successfully removed both acid contaminants, the removal efficiency of and water flow rate through the membranes were not sufficient to produce large volumes of electrolysis-grade water. In the present study, we investigated electrodialysis as a potential acid removable technique. Our studies have show a rapid and significant reduction in chloride and fluoride concentrations in the feed solution, while generating a relatively small volume of concentrated waste water. Electrodialysis has shown significant promise as the primary separation technique in ISRU water purification processes.

Technology Portfolio System↗
NASA NTRS2011

Electrostatic Precipitation of Dust in the Martian Atmosphere: Implications for the Utilization of Resources During Future Manned Exploration Missions

Future human missions to Mars will require the utilization of local resources for oxygen, fuel. and water. The In Situ Resource Utilization (ISRU) project is an active research endeavor at NASA to develop technologies that can enable cost effective ways to live off the land. The extraction of oxygen from the Martian atmosphere. composed primarily of carbon dioxide, is one of the most important goals of the Mars ISRU project. The main obstacle is the relatively large amount of dust present in the Martian atmosphere. This dust must be efficiently removed from atmospheric gas intakes for ISRU processing chambers. A common technique to achieve this removal on earth is by electrostatic precipitation, where large electrostatic fields are established in a localized region to precipitate and collect previously charged dust particles. This technique is difficult to adapt to the Martian environment, with an atmospheric pressure of about one-hundredth of the terrestrial atmosphere. At these low pressures. the corona discharges required to implant an electrostatic charge to the particles to be collected is extremely difficult to sustain and the corona easily becomes biopolar. which is unsuitable for particle charging. In this paper, we report on our successful efforts to establish a stable corona under Martian simulated conditions. We also present results on dust collecting efficiencies with an electrostatic precipitator prototype that could be effectively used on a future mission to the red planet

Calle, Carlos I.↗
NASA NTRS2016

Monitoring Drought Conditions in the Navajo Nation Using NASA Earth Observations

The Navajo Nation, a 65,700 sq km Native American territory located in the southwestern United States, has been increasingly impacted by severe drought events and changes in climate. These events are coupled with a lack of domestic water infrastructure and economic resources, leaving approximately one-third of the population without access to potable water in their homes. Current methods of monitoring drought are dependent on state-based monthly Standardized Precipitation Index value maps calculated by the Western Regional Climate Center. However, these maps do not provide the spatial resolution needed to illustrate differences in drought severity across the vast Nation. To better understand and monitor drought events and drought regime changes in the Navajo Nation, this project created a geodatabase of historical climate information specific to the area, and a decision support tool to calculate average Standardized Precipitation Index values for user-specified areas. The tool and geodatabase use Tropical Rainfall Monitoring Mission (TRMM) and Global Precipitation Monitor (GPM) observed precipitation data and Parameter-elevation Relationships on Independent Slopes Model modeled historical precipitation data, as well as NASA's modeled Land Data Assimilation Systems deep soil moisture, evaporation, and transpiration data products. The geodatabase and decision support tool will allow resource managers in the Navajo Nation to utilize current and future NASA Earth observation data for increased decision-making capacity regarding future climate change impact on water resources.

Ly, Vickie↗
DOE OSTI2024

Multistage Stochastic optimization for mid-term integrated generation and maintenance scheduling of cascaded hydroelectric system with renewable energy uncertainty

The uncertainties resulting from the escalating penetration of renewable energy resources pose severe challenges to the efficient operation of modern power systems. Hydroelectricity is characterized by its flexibility, controllability, and reliability, and thus becomes one of the most ideal energy resources to hedge against such uncertainties. This paper studies the mid-term integrated generation and maintenance scheduling of a cascaded hydroelectric system (CHS) consisting of multiple cascaded reservoirs and hydroelectric units. To precisely describe the mid-term water regulation policies, the hydraulic coupling relationship and water-energy nexus of CHS are incorporated into the proposed optimization model. The uncertainties of natural water inflow and the power outputs of wind/solar energy generation are taken into consideration and captured via a stochastic process modeled by a scenario tree. A multistage stochastic optimization (MSO) approach is developed to coordinate the complementary operations of multiple energy resources, by optimizing the mid-term water resource management, generation scheduling, and maintenance scheduling of CHS. The proposed MSO model is formulated as a large-scale mixed-integer linear program that presents significant computational intractability. To address this issue, a tailored Benders decomposition algorithm is developed. Two real-world case studies are conducted to demonstrate the capability and characteristics of the proposed model and algorithm. The computational results show that the proposed MSO model can exploit the flexibility of hydroelectricity to efficiently respond to variable wind and solar power, and reserve water resources for the generation in peak months to reduce the consumption of fossil fuel. Furthermore, the proposed solution approach also exhibits promising computational efficiency when handling large-scale models.

13 HYDRO ENERGY↗
DOE OSTI2023

Moisture Absorbing and Water Self‐Releasing from Hybrid Hydrogel Desiccants

Abstract Atmospheric moisture is a valuable resource for fresh water and potentially sustainable energy. However, direct harvesting water from moisture (the vapor form) remains the most challenging. Hybrid desiccants made from hydrogels embedded with salt offer promise in absorbing moisture. However, the desorption process often requires additional energy to heat the samples. Here, poly(acrylic acid) (PAA) hydrogels embedded with lithium chloride are prepared, demonstratng simultaneous moisture absorption and self‐release of liquid water at room temperature with 50–90% relative humidity. The water self‐releasing process can be separated into two distinct stages: 1) surface release, where water droplets grow on the hydrogel surface due to differences in nucleation and diffusion rates, and 2) bulk release, triggered by the collapse of polymer chains, subsequently releasing water from the hydrogel network. Factors such as salt concentration, hydrogel crosslinking density, and film thickness are investigated to better understand the moisture absorption and water‐releasing processes. Moreover, hydrophobic domains are introduced onto the salt‐embedded PAA films, creating an edge effect that enhances the droplet growth rates. When the hydrophobic domains are patterned, the movement of released water can be guided, resulting in a threefold increase in water removal rate attributed to gravitational force.

Chemistry↗
NASA NTRSDate not supplied

A Lunar Water ISRU System Study for Human-Scale Propellant Production

NASA’s plans to return to the moon in the Artemis campaign include intentions for sustainable surface operations. In-Situ Resource Utilization (ISRU) is key to enabling sustainability. The use of water, which has been identified in the lunar polar regions [1-4], could be pivotal to a sustainable architecture. While water has been identified, there is limited information regarding its form and distribution. The Lunar Water ISRU Measurement Study (LWIMS) [5] outlined the current state of knowledge regarding water resources on the moon, what information is lacking, and how to approach a measurement campaign to close those knowledge gaps. However the NASA timeline necessitates that lunar surface water prospecting, or reconnaissance, efforts and ISRU system design to occur in parallel. ISRU hardware and systems development must proceed without key resource knowledge. Yet, engineering design requires come constraints and targets to work to. The goal of this study was to define a set of lunar water reference cases, based on the cur-rent lunar water information, to help focus ISRU de-sign and planning. This approach is similar to an study focused on Mars resources called Mars Water ISRU Planning (MWIP) [6].

Lunar Water↗
DOE OSTI2021

Simulated Adhesive Response to Aging (CRADA 453 Final Report)

The goal of this project was to develop a suite of molecular models to investigate adhesive performance as a result of the presence of different levels of moisture. These different levels of moisture are accepted in the adhesives community to represent different states of aging. First, our team modeled the adhesive’s crosslinked structure. Next, we modeled adding water to the crosslinked structure and used high performance computing resources to simulate water diffusion through the bulk adhesive and possible sites for chain scission. Finally, we modeled the response of the simulated adhesive to tensile loads at various levels of moisture content. These simulations were validated by experimental characterization by the industry partner. We found that the Young’s modulus of the adhesive decreased by about 30% when the water content increased to 3 wt.%. Our simulations also identified the likely site where the polymer chain could break. Our integration of molecular level simulations and mechanical property predictions using high performance computing with experimental studies of a hydrated epoxy system has yielded fundamental insights that will help industry advance lightweight joining technologies.

36 MATERIALS SCIENCE↗
NASA NTRSDate not supplied

Using Open Standards and NASA Open Source Simulation Tools to Model Artemis Base Camp Mission Timelines

The United States’ National Aeronautics and Space Administration (NASA) has announced that the Artemis Program will return humans to the Moon, establishing a persistent presence with the Artemis Base Camp (ABC), and extend human exploration to Mars. The NASA Exploration Systems Simulations (NExSyS) team at NASA’s Johnson Space Center is using internationally developed simulation interoperability standards and NASA open source simulation tools to support Artemis concept, analysis, designs, development, training, and ultimately operations. The NExSyS team has been tasked to support early ABC architecture and mission analysis using mission time lines developed by the crew operations mission planning team. The NExSyS team is developing a distributed simulation framework with initial Artemis element implementations to model the ABC mission timelines using the international simulation interoperability standard High Level Architecture (HLA), the Simulation Interoperability Standards Organization’s Space Reference Federation Object Model (SpaceFOM), the NASA open source Trick Simulation Environment, and another NASA open source interface package called TrickHLA. The ABC architecture is composed of a number of key surface elements and resources. Some examples of modeled elements (also known as entities) are landers, habitats, rovers, logistics carriers, and astronauts. Some examples of modeled transferable and consumable resources are power, water, oxygen, nitrogen, scientific samples, and food. These entities and resources are modeled in a collection of individual simulations called Federates. A coordinated collection of interoperable federates is called a Federation and when these federates are tied together in a coordinated simulation run, it is referred to as a Federation Execution. The federates communicate through HLA using data exchange formats defined by a collection of machine readable files called Federation Object Models (FOMs). These FOM files are based on extensions to the SpaceFOM. This enables the instantiation and sharing of objects and interactions between federates in the federation. These provide for entity and resource tracking, object transfer, and data collection. Federate interactions are used to trigger events and notify federates of entity or resource transfers. For the initial implementation, the constituent federates are Trick-based simulations that use TrickHLA to provide the required HLA-base interoperability. These Trick-based simulations provide the required modeling for the individual Artemis elements along with the associated element resources. These federates provide a means to explore traverses between surface elements and exploration sites as scheduled in a mission timeline and explore the affects traverse times have on the overall mission timeline. The mission time lines are modeled using a Trick input file event handling capabilities. Each timeline operation is handled as individual simulation events, and triggered based on previous event status, time of operation, and simulated task completions. In addition, the ABC Federation can be used to perform Monte Carlo analysis. The Monte Carlo tool can vary the inputs, timings, and malfunctions to show how various contingencies in the mission can affect the mission timeline.

Keaton Craig Dodd↗
NASA NTRS2014

Gas Chromatograph Method Optimization Trade Study for RESOLVE: 20-meter Column v. 8-meter Column

RESOLVE is the payload on a Class D mission, Resource Prospector, which will prospect for water and other volatile resources at a lunar pole. The RESOLVE payload's primary scientific purpose includes determining the presence of water on the moon in the lunar regolith. In order to detect the water, a gas chromatograph (GC) will be used in conjunction with a mass spectrometer (MS). The goal of the experiment was to compare two GC column lengths and recommend which would be best for RESOLVE's purposes. Throughout the experiment, an Inficon Fusion GC and an Inficon Micro GC 3000 were used. The Fusion had a 20m long column with 0.25mm internal diameter (Id). The Micro GC 3000 had an 8m long column with a 0.32mm Id. By varying the column temperature and column pressure while holding all other parameters constant, the ideal conditions for testing with each column length in their individual instrument configurations were determined. The criteria used for determining the optimal method parameters included (in no particular order) (1) quickest run time, (2) peak sharpness, and (3) peak separation. After testing numerous combinations of temperature and pressure, the parameters for each column length that resulted in the most optimal data given my three criteria were selected. The ideal temperature and pressure for the 20m column were 95 C and 50psig. At this temperature and pressure, the peaks were separated and the retention times were shorter compared to other combinations. The Inficon Micro GC 3000 operated better at lower temperature mainly due to the shorter 8m column. The optimal column temperature and pressure were 70 C and 30psig. The Inficon Micro GC 3000 8m column had worse separation than the Inficon Fusion 20m column, but was able to separate water within a shorter run time. Therefore, the most significant tradeoff between the two column lengths was peak separation of the sample versus run time. After performing several tests, it was concluded that better detection via good peak separation with a longer run time is a better asset than moderate peak separation with a shorter run time. Even given that RESOLVE is highly interested in water and that mission timeline is of significant importance given the short seven-to-ten-day mission timeline, worse detection with an 8m column may lead to overlooking other substances existing on the moon that could advance planetary science. Thus, I recommend the 20m column. However, if mission timeline and water separation are deemed the highest priority, the 8m column should be selected due to its ability to separate water within a shorter run time than the 20m column.

Column↗
NASA NTRS2020

Searching for Hyperspectral Optical Proxies to Aid Chesapeake Bay Resource Managers in the Detection of Poor Water Quality

Shellfish aquaculture is a growing industry in the Chesapeake Bay. As population grows near the coast, extreme weather events cause a greater volume of pollutant runoff from impervious surfaces and agricultural lands. Resource managers who monitor shellfish beds need reliable information on a variety of water quality indicators at higher frequency than is possible through field monitoring programs and at a higher level of detail than current satellite products can provide. Although many factors causing degraded water quality that can impact human health are not currently discernable by traditional multispectral techniques, hyperspectral imagery offers a new opportunity to detect phytoplankton communities associated with harmful algal blooms and biotoxin production. Together with resource managers in their routine monitoring of sites around the bay from small boats, we have been exploring remotely sensed optical proxies for the detection of harmful algal blooms and sewage. Early warning by remote sensing could guide sampling and improve the efficiency of shellfish bed closures, ultimately improving health outcomes for humans and animals. An extensive network of routine sampling by Chesapeake Bay Program managers makes this is an ideal location to develop and test future satellite data products to support management decisions. Next generation hyperspectral measurements from the future Plankton Aerosol Cloud ocean Ecosystem (PACE) mission at nearly daily frequency, combined with the potential of higher spatial resolution from the Surface Biology and Geology (SBG) observing system recommended in the recent Decadal Survey, along with high frequency observations from the newly selected Geostationary Littoral Imaging and Monitoring Radiometer (GLIMR) Earth Venture Instrument make this a critical time for defining the needs of the aquaculture and resource management community to save lives, time, and money.

Schollaert Uz, Stephanie↗
DOE OSTI2020

Evaluating cross-sectoral impacts of climate change and adaptations on the energy-water nexus: a framework and California case study

Abstract Electricity and water systems are inextricably linked through water demands for energy generation, and through energy demands for using, moving, and treating water and wastewater. Climate change may stress these interdependencies, together referred to as the energy-water nexus, by reducing water availability for hydropower generation and by increasing irrigation and electricity demand for groundwater pumping, among other feedbacks. Further, many climate adaptation measures to augment water supplies—such as water recycling and desalination—are energy-intensive. However, water and electricity system climate vulnerabilities and adaptations are often studied in isolation, without considering how multiple interactive risks may compound. This paper reviews the fragmented literature and develops a generalized framework for understanding these implications of climate change on the energy-water nexus. We apply this framework in a case study to quantify end-century direct climate impacts on California’s water and electricity resources and estimate the magnitude of the indirect cross-sectoral feedback of electricity demand from various water adaptation strategies. Our results show that increased space cooling demand and decreased hydropower generation are the most significant direct climate change impacts on California’s electricity sector by end-century. In California’s water sector, climate change impacts directly on surface water availability exceed demand changes, but have considerable uncertainty, both in direction and magnitude. Additionally, we find that the energy demands of water sector climate adaptations could significantly affect California’s future electricity system needs. If the worst-case water shortage occurs under climate change, water-conserving adaptation measures can provide large energy savings co-benefits, but other energy-intensive water adaptations may double the direct impacts of climate change on the state’s electricity resource requirement. These results highlight the value of coordinated adaptation planning between the energy and water sectors to achieve mutually beneficial solutions for climate resilience.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2017

Extraction of Volatiles from Regolith or Soil on Mars, the Moon, and Asteroids

NASA's Advanced Exploration Systems ISRU Technology Project is evaluating concepts to extract water from all resource types Near-term objectives: Produce high-fidelity mass, power, and volume estimates for mining and processing systems Identify critical challenges for development focus Begin demonstration of component and subsystem technologies in relevant environment Several processor types: Closed processors either partially or completely sealed during processing Open air processors operates at Mars ambient conditions In-situ processors Extract product directly without excavation of raw resource Design features Elimination of sweep gas reduces dust particles in water condensate Pressure maintained by height of soil in hopper Model developed to evaluate key design parameters Geometry: conveyor diameter, screw diameter, shaft diameter, flight spacing and pitch Operational: screw speed vs. screw length (residence time) Thermal: Heat flux, heat transfer to soil Testing to demonstrate feasibility and performance Agglomeration, clogging Pressure rise forced flow to condenser.

Extration↗
NASA NTRSDate not supplied

ISRU: Using Biology to Produce Food and Oxygen from Resources on Mars

Any crewed mission to Mars is a “biological” mission. As we move farther away from Earth, we will have to produce the required food, water and nutrient resources to sustain the crew in route or on the surface of other planetary bodies. Critical nutrients, like vitamins, have been shown to degrade in our current food system and represent a risk to long term crew health. One way to address this problem is by developing reliable Biological Life Support Systems (BLSS) that can provide fresh, nutrient-rich foods. Much work in this area will be done as we learn to live and work on the Moon. Systems developed for the Moon should also work on Mars, but will not be designed to take advantage of resources that Mars offers: CO2, more abundant water, and a day length similar to Earth’s. The photosynthetic portion of a BLSS can act as an ISRU element on Mars by providing human life support needs. There is an urgent need to understand how to build components of a fully functional BLSS. One Mars Exploration Program Analysis Group (MEPAG) goal relates to this area.

B. M. Link↗
DOE OSTI2021

The implications of future climate change on the blue water footprint of hydropower in the contiguous US

As the largest renewable energy source, hydropower is essential to the sustainability of the global energy market. However, a considerable amount of water can be lost in the form of evaporation from the associated multipurpose reservoirs, and hence enlarge the blue water footprint (BWF) of hydropower in a warming climate. To facilitate the sustainable management of both water and energy resources under the impact of climate change in the contiguous United States (CONUS), the BWF values of 143 major multipurpose reservoirs were evaluated during the historical period (1985–2014) and two future periods (2020–2049 and 2070–2099). The historical reservoir evaporation loss was calculated using the Landsat-based reservoir surface area and a new evaporation rate algorithm that considers the heat storage effect. Future projections of runoff availability, hydropower generation, and reservoir evaporation were estimated based on the downscaled climate model ensemble from phase 5 of the Coupled Model Intercomparison Project (CMIP5). It was found that the BWF for the CONUS is highly spatially heterogeneous, with an average value of 26.2 m 3 /MWh in the historical period. In the future, the BWF values are projected to increase under both Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios. This is especially noticeable under RCP 8.5, which has an average BWF value of 30.2 m 3 /MWh for 2070–2099 (increasing by 15.3% from 26.2 m 3 /MWh). The uncertainty ranges increase even more, from 3.4 m 3 /MWh during 2020–2049 to 5.7 m 3 /MWh during 2070–2099. These findings can benefit water and energy resources management in identifying suitable environmental, economic, operational, and investment strategies for multipurpose reservoirs in a changing environment.

13 HYDRO ENERGY↗
NASA NTRS2014

Mass Reduction: The Weighty Challenge for Exploration Space Flight

Meeting nutritional and acceptability requirements is critical for the food system for an exploration class space mission. However, this must be achieved within the constraints of available resources such as water, crew time, stowage volume, launch mass and power availability.  Due to resource constraints, exploration class missions are not expected to have refrigerators or freezers for food storage, and current per person food mass must be reduced to improve mission feasibility.  The Packaged Food Mass Reduction Trade Study (Stoklosa, 2009) concluded that the mass of the current space food system can be effectively reduced by decreasing water content of certain foods and offering nutrient dense substitutes, such as meal replacement bars and beverages. Target nutrient ranges were established based on the nutritional content of the current breakfast and lunch meals in the ISS standard menu. A market survey of available commercial products produced no viable options for meal replacement bar or beverage products. New prototypes for both categories were formulated to meet target nutrient ranges. Samples of prototype products were packaged in high barrier packaging currently used for ISS and underwent an accelerated shelf life study at 31 degC and 41 degC (50% RH) for 24 weeks. Samples were assessed at the following time points: Initial, 6 weeks, 12 weeks, and 24 weeks. Testing at each time point included the following: color, texture, water activity, acceptability, and hexanal analysis (for food bars only). Proof of concept prototypes demonstrated that meal replacement food bars and beverages can deliver a comparable macronutrient profile while reducing the overall mass when compared to the ISS Standard Menu. Future work suggestions for meal replacement bars: Reformulation to include ingredients that reduce hardness and reduce browning to increase shelf life. Micronutrient analysis and potential fortification. Sensory evaluation studies including satiety tests and menu fatigue. Water Intake Analysis: The water in thermostabilized foods is considered as part of a crewmember's daily water intake. Extensive meal replacement would require further analyses to determine if additional water provisioning would be required per crewmember negating some of the mass savings.

Kloeris, Vickie L.↗
DOE OSTI2025

Optimization of Delignified Wood Rods for Interfacial Solar Evaporation

Interfacial solar evaporation using three-dimensional evaporator materials has shown promise to achieve high evaporation rates exceeding the photothermal limit for water treatment and resource recovery processes. However, challenges remain in optimizing the material geometry to balance the vertical capillary uptake of water and the rate of evaporation to achieve both stable and high evaporation rates. Delignified wood can serve as a highly porous and hydrophilic substrate material to achieve high evaporation rates. In this work, we designed a suspended biochar-coated delignified wood rod evaporator and investigated the influence of its geometric parameters on its evaporation performance. The height of the evaporator exposed to air for evaporation was observed to be an important parameter in governing the evaporation rate, as shorter evaporators limited the available surface area for evaporation, but taller evaporators could not achieve sufficient rates of capillary uptake to maintain stable evaporation rates over 24 h under 1-sun illumination (1 kW m –2 ). In conclusion, the exposed height of the evaporator was optimized to achieve an average hourly evaporation rate of 3.05 ± 0.23 kg m –2 h –1 , which could be maintained in saline solutions containing up to 5 wt % NaCl.

Coating materials↗