This article presents an adaptive intelligent control strategy applied to a lumped-parameter evaporator model,i.e.,a simplified dynamic representation treating the evaporator as a single thermal node with uniform temp...This article presents an adaptive intelligent control strategy applied to a lumped-parameter evaporator model,i.e.,a simplified dynamic representation treating the evaporator as a single thermal node with uniform temperature distribution,suitable for control design due to its balance between physical fidelity and computational simplicity.The controller uses a wavelet-based neural proportional,integral,derivative(PID)controller with IIR filtering(infinite impulse response).The dynamic model captures the essential heat and mass transfer phenomena through a nonlinear energy balance,where the cooling capacity“Qevap”is expressed as a non-linear function of the compressor frequency and the temperature difference,specifically,Q_(evap)=k_(1)u(T_(in)−T_(e))with u as compressor frequency,Te evaporator temperature,and Tin inlet fluid temperature.The operating conditions of the system,in general terms,focus on the following variables,the overall thermal capacity is 1000 J/K,typical for small-capacity heat exchangers,The mass flow is 0.05 kg/s,typical for secondary liquid cooling circuits,the overall loss coefficient of 50 W/K that corresponds to small evaporators with partial insulation,the temperatures(inlet)of 10℃and the temperature of environment of 25℃,thermal load of 200 W that corresponds to a small-scaled air conditioning applications.To handle system nonlinearities and improve control performance,aMorlet wavelet-based neural network(Wavenet)is used to dynamically adjust the PID gains online.An IIR filter is incorporated to smooth the adaptive gains,improving stability and reducing oscillations.In contrast to prior wavelet-or neural-adaptive PID controllers in HVAC applications,which typically adjust gains without explicit filtering or not tailored to evaporator dynamics,this work introduces the first PID–Wavenet scheme augmented with an IIR-based stabilization layer,specifically designed to address the combined challenges of nonlinear evaporator behavior,gain oscillation,and real-time implementability.The proposed controller(PID-Wavenet+IIR)is implemented and validated inMATLAB/Simulink,demonstrating superior performance compared to a conventional PID tuned using Simulink’s auto-tuning function.Key results include a reduction in settling time from 13.3 to 8.2 s,a reduction in overshoot from 3.5%to 0.8%,a reduction in steady-state error from 0.12℃ to 0.02℃and a 13%reduction in energy overall consumption.The controller also exhibits greater robustness and adaptability under varying thermal loads.This explicit integration of wavelet-driven adaptation with IIR-filtered gain shaping constitutes the main methodological contribution and novelty of the work.These findings validate the effectiveness of the wavelet-based adaptive approach for advanced thermal management in refrigeration and HVAC systems,with potential applications in controlling variable-speed compressors,liquid chillers,and compact cooling units.展开更多
The increasing scarcity of freshwater resources has driven the rapid emergence of solar-driven interfacial evaporators(SDIEs)as a sustainable approach to harvest fresh water by utilizing solar energy.Lignocellulosic b...The increasing scarcity of freshwater resources has driven the rapid emergence of solar-driven interfacial evaporators(SDIEs)as a sustainable approach to harvest fresh water by utilizing solar energy.Lignocellulosic biomass,featuring natural abundance,excellent renewability,unique natural structures,and superior biodegradability compared to the synthetic polymers,is highly attractive for constructing solar steam generators.This review aims to offer an innovative and in-depth insight into designing and optimizing highperformance integrated solar interfacial evaporators derived from renewable lignocellulosic biomass.First,the structural characteristics of lignocellulosic biomass are briefly introduced,serving as photothermal layer or supporting substrates in SDIEs.Secondly,the fabrication methods and processing technologies of lignocellulosic biomass-based evaporators are summarized from the perspective of photothermal layer and supporting substrates.Next,the most recent advances of regulation and optimization strategies are proposed to improve evaporation efficiency.Subsequently,this review summarizes the diverse functionalities of SDIEs,including desalination,power generation,wastewater treatment and antimicrobial,atmospheric water harvesting,and photocatalytic hydrogen production.Finally,the challenges in this field and outlook on the future development are discussed,which are anticipated to provide new opportunities for the advancement of lignocellulosic biomass-based SDIEs.展开更多
While desalination is a key solution for global freshwater scarcity,its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems.Solar interfa...While desalination is a key solution for global freshwater scarcity,its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems.Solar interfacial evaporation offers sustainable management potential,yet inevitable salt nucleation at evaporation interfaces degrades photothermal conversion and operational stability via light scattering and pathway blockage.Inspired by the mangrove leaf,we propose a photothermal 3D polydopamine and polypyrrole polymerized spacer fabric(PPSF)-based upward hanging model evaporation configuration with a reverse water feeding mechanism.This design enables zero-liquiddischarge(ZLD)desalination through phase-separation crystallization.The interconnected porous architecture and the rough surface of the PPSF enable superior water transport,achieving excellent solar-absorbing efficiency of 97.8%.By adjusting the tilt angle(θ),the evaporator separates the evaporation and salt crystallization zones via controlled capillary-driven brine transport,minimizing heat dissipation from brine discharge.At an optimal tilt angle of 52°,the evaporator reaches an evaporation rate of 2.81 kg m^(−2) h^(−1) with minimal heat loss(0.366 W)under 1-sun illumination while treating a 7 wt%waste brine solution.Furthermore,it sustains an evaporation rate of 2.71 kg m^(−2) h^(−1) over 72 h while ensuring efficient salt recovery.These results highlight a scalable,energy-efficient approach for sustainable ZLD desalination.展开更多
Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a ...Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a fabric-based Janus interracial evaporator is efficiently fabricated on a large scale by integrating an extremely innovative self-designed melt-centrifugal spinning technology with spray coating technology.The prepared fabric-based Janus interfacial evaporator has differential hydrophilicity,uneven surfaces,and channels that allow moisture escape.Benefiting from the excellent photothermai conversion of graphene oxide and the charge transfer actions of titanium dioxide,such a multifunction evaporator can reach a high evaporation rate of 1.72 kg m^(-2)h^(-1)under 1 sun irradiation,a superior antibacterial rate of 99%,excellent photocatalytic degradation,and effective thermoelectric ability simultaneously.Moreover,it also shows fantastic performance in salt resistance,recyclable evaporation,and real desalination,This work demonstrates a high-efficiency,cost-effective,multifunctional,and scalable strategy for high-performance fiber fabrics solar interfacial evaporation.展开更多
Enhancing wastewater treatment efficiency through innovative technologies is paramount in addressing global environmental challenges.This study explores utilizing stereoscopic hydrogel evaporators combined with renewa...Enhancing wastewater treatment efficiency through innovative technologies is paramount in addressing global environmental challenges.This study explores utilizing stereoscopic hydrogel evaporators combined with renewable energy sources to optimize wastewater treatment processes.A cross-linked super absorbent polymer(SAP)hydrogel was synthesized using acrylic acid and 2-hydroxyethyl methacrylate monomers and integrated with a light-absorbing carbon membrane to form a solar-assisted evaporator(MSAP).The MSAP achieved a high evaporation rate of 3.08 kg m^(-2)·h^(-1)and a photothermal conversion efficiency of 94.27%.It demonstrated excellent removal efficiency for dye-polluted wastewater,significantly reducing concentrations of pollutants.The MSAP maintained high performance in outdoor conditions,showcasing its potential for real-world applications.This approach,incorporating both solar and wind energy,significantly boosts water evaporation rates and presents a promising,eco-friendly solution for sustainable wastewater treatment within the circular development framework.展开更多
The solar interfacial evaporation has a broad application prospect in the fields of steam generation and seawater desalination to deal with the global shortage of fresh-water resources.Bamboo is a great material for s...The solar interfacial evaporation has a broad application prospect in the fields of steam generation and seawater desalination to deal with the global shortage of fresh-water resources.Bamboo is a great material for solar interface evaporators because of its low thermal conductivity and inherent micro-channel porous structure.In this paper,a novel bamboo-based solar interface evaporator with a bionic ripple wave surface structure has been proposed.The subsequent evaporation experiments have been conducted to investigate the salt resistance,stability and water absorption of the bionic ripple bamboo based solar interface evaporator.The results have exhibited that the bamboo's water absorption has been enhanced after carbonization modification.Besides,it should be pointed out that this bamboo-based evaporator’s evaporation rate has dropped during the prolonged simulated seawater evaporation experiment,yet it remained fairly consistent at approximately 1.626 kg·m^(-2)·h^(-1).The appearance for this experimental phenomenon is the decrease of the floatability of the evaporator constricted by the stored water body absorbed by the evaporator and the deposition of NaCl crystals at the photothermal interface.Besides,compared with the plate-structure evaporator,the salt deposition in the evaporator equipped with the bionic ripple wave surface structure is greatly improved.In regard to its advantages in low cost,environmental friendliness,good salt tolerance and high evaporation rate,the bamboo-based solar interface evaporator with a bionic ripple wave surface structure can provide a potential solution to the global problem of fresh-water shortage.展开更多
The dynamics of vapor−liquid−solid(V−L−S)flow boiling in fluidized bed evaporators exhibit inherent complexity and chaotic behavior,hindering accurate prediction of pressure drop signals.To address this challenge,this...The dynamics of vapor−liquid−solid(V−L−S)flow boiling in fluidized bed evaporators exhibit inherent complexity and chaotic behavior,hindering accurate prediction of pressure drop signals.To address this challenge,this study proposes an innovative hybrid approach that integrates wavelet neural network(WNN)with chaos analysis.By leveraging the Cross-Correlation(C−C)method,the minimum embedding dimension for phase space reconstruction is systematically calculated and then adopted as the input node configuration for the WNN.Simulation results demonstrate the remarkable effectiveness of this integrated method in predicting pressure drop signals,advancing our understanding of the intricate dynamic phenomena occurring with V−L−S fluidized bed evaporators.Moreover,this study offers a novel perspective on applying advanced data-driven techniques to handle the complexities of multi-phase flow systems and highlights the potential for improved operational prediction and control in industrial settings.展开更多
Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a n...Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a new two-dimensional hydrogel evaporator is urgently needed to alleviate this problem.Here,a double layer hydrogel evaporator was designed by twice vacuum filtration.Furthermore,through the arched design and the introduction of concentrated brine drainage system,the hydrogel evaporator has enhanced water transportation and tailored water transportation path.Such a unique drainage evaporation system greatly improves the stability of the evaporator.Thereby,a good balance is established between photothermal conversion and water supply,and solar energy is utilized efficiently.It can remain stable in continuous evaporation for up to 12 h with an excellent evaporation rate of 2.70 kg m^(-2)h^(-1)under 1 sun irradiation.Meanwhile,the drainage system realized the 1.8×10^(-10)mol m^(-2)s^(-1)diffusion flux of concentrated brine.Through one-time freeze-drying preparation,an arch-shaped drainage evaporator was used to prepare an evaporation area of more than 20 cm^(2).With the self-made condensate collecting device in outdoor environment,the fresh water yield reaches 7.5 L m^(-2)d^(-1).This provides a new scheme for building a new hydrogel evaporator and solving the fresh water crisis.展开更多
Global freshwater scarcity and energy shortages demand integrated solutions.To overcome limitations of traditional solar evaporators,such as salt accumulation,thermal dissipation,and material scalability issues,this s...Global freshwater scarcity and energy shortages demand integrated solutions.To overcome limitations of traditional solar evaporators,such as salt accumulation,thermal dissipation,and material scalability issues,this study presents a biomass-derived three-dimensional(3D)aerogel-based dual-function solar evaporator that simultaneously achieves ultra-high freshwater production and continuous electricity generation.By ingeniously integrating a superhydrophobic inner layer for thermal insulation and buoyancy with a hydrophilic photothermal outer layer for rapid water transport and solar absorption,our design overcomes the trade-offs between evaporation efficiency,salt resistance,and energy loss.The evaporator exhibits exceptional dual performance:an evaporation rate of 3.87 kg m^(-2)h-1(1 sun)and a sustained open-circuit voltage of 222.6 mV,surpassing most reported systems.This synergy originates from ion gradient-driven streaming potentials enabled by selective Na^(+) transport through–COOH/C–OH functionalized microchannels,as verified by molecular dynamics simulations.Crucially,the fabrication process utilizes low-cost biomass materials and scalable techniques,demonstrating significant potential for commercialization.This work not only provides a mechanistic understanding of ion-selective transport in dual-function evaporators but also establishes a paradigm for sustainable co-production of clean water and renewable energy,addressing two pressing global challenges through a single and scalable platform.展开更多
The agitated thin-film evaporator(ATFE)plays a crucial role in evaporation and concentration processes.The design of the scraper for processing high-viscosity non-Newtonian fluids in the ATFE is complex.The intricate ...The agitated thin-film evaporator(ATFE)plays a crucial role in evaporation and concentration processes.The design of the scraper for processing high-viscosity non-Newtonian fluids in the ATFE is complex.The intricate scraping action of the scraper introduces gas into the liquid film,leading to the formation of a gas ring along the wall.This process subsequently reduces wall heat flow,thereby affecting heat transfer.Computational fluid dynamics(CFD)is used to simulate the flow field of the non-Newtonian fluid in the ATFE.The investigation focuses on understanding the mechanism behind the formation of gas rings in the liquid film and proposes methods to prevent their formation.The results demonstrate a transition of the gas from a gas ring suspended in the liquid to a gas ring attached to the wall after entering the liquid film.The scraping action around the circumference of the scraper helps to expel gas rings,indicating the necessity of adjusting the scraper arrangement and increasing the frequency of scraping to enhance gas ring expulsion.The spiral motion of the bow wave serves as the source of gas entry into the liquid film.Therefore,the rotation speed can appropriately increase to reduce the size of the bow wave,thereby inhibiting the formation of the gas ring from the source.This research investigates the mechanism of gas ring generation and expulsion,offering theoretical guidance for processing high-viscosity non-Newtonian materials in the flow field of the ATFE.展开更多
Frost accumulation on the evaporator fins of air source heat pumps(ASHPs)severely degrades heat transfer performance and overall system efficiency.To address this,the present study employs computational fluid dynamics...Frost accumulation on the evaporator fins of air source heat pumps(ASHPs)severely degrades heat transfer performance and overall system efficiency.To address this,the present study employs computational fluid dynamics(CFD)to investigate how fin spacing influences frosting behavior,emphasizing the coupled evolution of frost thickness,density,airflow,and temperature distribution within fin channels.Results reveal that fin spacing is a key parameter governing both the extent and rate of frost growth.Wider fin spacing enhances frost accumulation,with a final frost mass of 6.41 g at 12 mm,about 71.8%higher than at 4 mm.In contrast,narrower spacing suppresses frost formation by accelerating airflow.The frost layer exhibits a distinct two-stage growth pattern:at 12 mm spacing,the early-stage average thickness growth rate reaches 0.021 mm/min,nearly 4.3 times that at 4 mm.Frost density follows similar initial trends across different spacings but diverges later due to thermal resistance and airflow variations.展开更多
The loop heat pipe with a flat evaporator is mainly divided into two forms:rectangular evaporator and disk-shaped evaporator.The rectangular evaporator has advantages such as low heat leakage,a thin shell,and a large ...The loop heat pipe with a flat evaporator is mainly divided into two forms:rectangular evaporator and disk-shaped evaporator.The rectangular evaporator has advantages such as low heat leakage,a thin shell,and a large contact area compared to the disk-shaped evaporator.However,most of the research on rectangular evaporators focuses onworking fluids such as water,methanol,and acetone,when theseworking fluids are in operation,the internal pressure of the evaporator is less than atmospheric pressure.Ammonia,propylene,and other working fluids can also be utilized in the loop heat pipe,these working fluids demonstrate better performance when operating within other temperature intervals,for example,the operating temperature range of ammonia is−20℃to 50℃,however,in an atmospheric pressure environment,it is very difficult for the shell of the rectangular evaporator to withstand the saturated vapor pressure of the working fluid.This paper designs a rectangular flat plate loop heat pipe that can use ammonia as the working fluid.The internal reinforcing structure is used to improve the pressure strength of the shell.The secondary wick connects the compensation chamber and the capillary wick hydraulically.The experiment indicates that this kind of rectangular evaporator is unaffected by the position,and the secondary wick can effectively supply liquid under different angles.The thermal resistance of the evaporator wall was analyzed,and it was found that the thermal resistance of the evaporator wall was the main component of the thermal resistance of the system.The heat transfer capacities of 460 W@0.5 m and 200W@10 m were tested.The test results indicate that by setting a reinforcing structure inside the flat plate evaporator,the evaporator can withstand internal pressure.Combined with the design of the secondary wick,the flat plate evaporator can use working fluids with different pressures,expanding the range of available working fluids.展开更多
文摘This article presents an adaptive intelligent control strategy applied to a lumped-parameter evaporator model,i.e.,a simplified dynamic representation treating the evaporator as a single thermal node with uniform temperature distribution,suitable for control design due to its balance between physical fidelity and computational simplicity.The controller uses a wavelet-based neural proportional,integral,derivative(PID)controller with IIR filtering(infinite impulse response).The dynamic model captures the essential heat and mass transfer phenomena through a nonlinear energy balance,where the cooling capacity“Qevap”is expressed as a non-linear function of the compressor frequency and the temperature difference,specifically,Q_(evap)=k_(1)u(T_(in)−T_(e))with u as compressor frequency,Te evaporator temperature,and Tin inlet fluid temperature.The operating conditions of the system,in general terms,focus on the following variables,the overall thermal capacity is 1000 J/K,typical for small-capacity heat exchangers,The mass flow is 0.05 kg/s,typical for secondary liquid cooling circuits,the overall loss coefficient of 50 W/K that corresponds to small evaporators with partial insulation,the temperatures(inlet)of 10℃and the temperature of environment of 25℃,thermal load of 200 W that corresponds to a small-scaled air conditioning applications.To handle system nonlinearities and improve control performance,aMorlet wavelet-based neural network(Wavenet)is used to dynamically adjust the PID gains online.An IIR filter is incorporated to smooth the adaptive gains,improving stability and reducing oscillations.In contrast to prior wavelet-or neural-adaptive PID controllers in HVAC applications,which typically adjust gains without explicit filtering or not tailored to evaporator dynamics,this work introduces the first PID–Wavenet scheme augmented with an IIR-based stabilization layer,specifically designed to address the combined challenges of nonlinear evaporator behavior,gain oscillation,and real-time implementability.The proposed controller(PID-Wavenet+IIR)is implemented and validated inMATLAB/Simulink,demonstrating superior performance compared to a conventional PID tuned using Simulink’s auto-tuning function.Key results include a reduction in settling time from 13.3 to 8.2 s,a reduction in overshoot from 3.5%to 0.8%,a reduction in steady-state error from 0.12℃ to 0.02℃and a 13%reduction in energy overall consumption.The controller also exhibits greater robustness and adaptability under varying thermal loads.This explicit integration of wavelet-driven adaptation with IIR-filtered gain shaping constitutes the main methodological contribution and novelty of the work.These findings validate the effectiveness of the wavelet-based adaptive approach for advanced thermal management in refrigeration and HVAC systems,with potential applications in controlling variable-speed compressors,liquid chillers,and compact cooling units.
基金supported by grants from National Natural Science Foundation of China(224708046,22508229,22278049)Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)+1 种基金Xingliao Talent Program-Young Top Talent(XLYC2403126)Liaoning Provincial Basic Scientific Research Project for Higher Education(LJ212510152013)。
文摘The increasing scarcity of freshwater resources has driven the rapid emergence of solar-driven interfacial evaporators(SDIEs)as a sustainable approach to harvest fresh water by utilizing solar energy.Lignocellulosic biomass,featuring natural abundance,excellent renewability,unique natural structures,and superior biodegradability compared to the synthetic polymers,is highly attractive for constructing solar steam generators.This review aims to offer an innovative and in-depth insight into designing and optimizing highperformance integrated solar interfacial evaporators derived from renewable lignocellulosic biomass.First,the structural characteristics of lignocellulosic biomass are briefly introduced,serving as photothermal layer or supporting substrates in SDIEs.Secondly,the fabrication methods and processing technologies of lignocellulosic biomass-based evaporators are summarized from the perspective of photothermal layer and supporting substrates.Next,the most recent advances of regulation and optimization strategies are proposed to improve evaporation efficiency.Subsequently,this review summarizes the diverse functionalities of SDIEs,including desalination,power generation,wastewater treatment and antimicrobial,atmospheric water harvesting,and photocatalytic hydrogen production.Finally,the challenges in this field and outlook on the future development are discussed,which are anticipated to provide new opportunities for the advancement of lignocellulosic biomass-based SDIEs.
基金supported by National Key Research and Development Program of China(2022YFB3804902,2022YFB3804900)the National Natural Science Foundation of China(52203226,52161145406,42376045)the Fundamental Research Funds for the Central Universities(2232024Y-01,2232025D-02).
文摘While desalination is a key solution for global freshwater scarcity,its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems.Solar interfacial evaporation offers sustainable management potential,yet inevitable salt nucleation at evaporation interfaces degrades photothermal conversion and operational stability via light scattering and pathway blockage.Inspired by the mangrove leaf,we propose a photothermal 3D polydopamine and polypyrrole polymerized spacer fabric(PPSF)-based upward hanging model evaporation configuration with a reverse water feeding mechanism.This design enables zero-liquiddischarge(ZLD)desalination through phase-separation crystallization.The interconnected porous architecture and the rough surface of the PPSF enable superior water transport,achieving excellent solar-absorbing efficiency of 97.8%.By adjusting the tilt angle(θ),the evaporator separates the evaporation and salt crystallization zones via controlled capillary-driven brine transport,minimizing heat dissipation from brine discharge.At an optimal tilt angle of 52°,the evaporator reaches an evaporation rate of 2.81 kg m^(−2) h^(−1) with minimal heat loss(0.366 W)under 1-sun illumination while treating a 7 wt%waste brine solution.Furthermore,it sustains an evaporation rate of 2.71 kg m^(−2) h^(−1) over 72 h while ensuring efficient salt recovery.These results highlight a scalable,energy-efficient approach for sustainable ZLD desalination.
基金the National Key Research and Development Program of China(Grant No.2022YFC3901902)the National Natural Science Foundation of China(Grant Nos.52203037,52103031,and 52073107)。
文摘Fiber fabrics have been wildly utilized for solar interracial evaporators to address freshwater scarcity.However,the complex and expensive manufacturing processes remain limited to their scalable development.Herein,a fabric-based Janus interracial evaporator is efficiently fabricated on a large scale by integrating an extremely innovative self-designed melt-centrifugal spinning technology with spray coating technology.The prepared fabric-based Janus interfacial evaporator has differential hydrophilicity,uneven surfaces,and channels that allow moisture escape.Benefiting from the excellent photothermai conversion of graphene oxide and the charge transfer actions of titanium dioxide,such a multifunction evaporator can reach a high evaporation rate of 1.72 kg m^(-2)h^(-1)under 1 sun irradiation,a superior antibacterial rate of 99%,excellent photocatalytic degradation,and effective thermoelectric ability simultaneously.Moreover,it also shows fantastic performance in salt resistance,recyclable evaporation,and real desalination,This work demonstrates a high-efficiency,cost-effective,multifunctional,and scalable strategy for high-performance fiber fabrics solar interfacial evaporation.
基金financially supported by the“Qing-Lan”Project of Jiangsu ProvinceTop-notch Academic Programs Project of Jiangsu Higher Education Institutions(TAPP)the start-up fund from Yangzhou University。
文摘Enhancing wastewater treatment efficiency through innovative technologies is paramount in addressing global environmental challenges.This study explores utilizing stereoscopic hydrogel evaporators combined with renewable energy sources to optimize wastewater treatment processes.A cross-linked super absorbent polymer(SAP)hydrogel was synthesized using acrylic acid and 2-hydroxyethyl methacrylate monomers and integrated with a light-absorbing carbon membrane to form a solar-assisted evaporator(MSAP).The MSAP achieved a high evaporation rate of 3.08 kg m^(-2)·h^(-1)and a photothermal conversion efficiency of 94.27%.It demonstrated excellent removal efficiency for dye-polluted wastewater,significantly reducing concentrations of pollutants.The MSAP maintained high performance in outdoor conditions,showcasing its potential for real-world applications.This approach,incorporating both solar and wind energy,significantly boosts water evaporation rates and presents a promising,eco-friendly solution for sustainable wastewater treatment within the circular development framework.
基金financially supported by the National Natural Science Foundation of China(12,405,179)the Natural Science Foundation of Hunan Province(2023JJ40744)+1 种基金the Natural Science Foundation of Hunan Province(2025JJ50227)the High Performance Computing Center of Central South University(2025JJ50226).
文摘The solar interfacial evaporation has a broad application prospect in the fields of steam generation and seawater desalination to deal with the global shortage of fresh-water resources.Bamboo is a great material for solar interface evaporators because of its low thermal conductivity and inherent micro-channel porous structure.In this paper,a novel bamboo-based solar interface evaporator with a bionic ripple wave surface structure has been proposed.The subsequent evaporation experiments have been conducted to investigate the salt resistance,stability and water absorption of the bionic ripple bamboo based solar interface evaporator.The results have exhibited that the bamboo's water absorption has been enhanced after carbonization modification.Besides,it should be pointed out that this bamboo-based evaporator’s evaporation rate has dropped during the prolonged simulated seawater evaporation experiment,yet it remained fairly consistent at approximately 1.626 kg·m^(-2)·h^(-1).The appearance for this experimental phenomenon is the decrease of the floatability of the evaporator constricted by the stored water body absorbed by the evaporator and the deposition of NaCl crystals at the photothermal interface.Besides,compared with the plate-structure evaporator,the salt deposition in the evaporator equipped with the bionic ripple wave surface structure is greatly improved.In regard to its advantages in low cost,environmental friendliness,good salt tolerance and high evaporation rate,the bamboo-based solar interface evaporator with a bionic ripple wave surface structure can provide a potential solution to the global problem of fresh-water shortage.
基金supported by the open foundation of State Key Laboratory of Chemical Engineering(SKL-ChE-22B01)the Natural Science Foundation of China(22008169).
文摘The dynamics of vapor−liquid−solid(V−L−S)flow boiling in fluidized bed evaporators exhibit inherent complexity and chaotic behavior,hindering accurate prediction of pressure drop signals.To address this challenge,this study proposes an innovative hybrid approach that integrates wavelet neural network(WNN)with chaos analysis.By leveraging the Cross-Correlation(C−C)method,the minimum embedding dimension for phase space reconstruction is systematically calculated and then adopted as the input node configuration for the WNN.Simulation results demonstrate the remarkable effectiveness of this integrated method in predicting pressure drop signals,advancing our understanding of the intricate dynamic phenomena occurring with V−L−S fluidized bed evaporators.Moreover,this study offers a novel perspective on applying advanced data-driven techniques to handle the complexities of multi-phase flow systems and highlights the potential for improved operational prediction and control in industrial settings.
基金the financial support of the National Natural Science Foundation of China(No.52075309)the Youth Innovation Team of Shaanxi Universities(21JP021)。
文摘Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a new two-dimensional hydrogel evaporator is urgently needed to alleviate this problem.Here,a double layer hydrogel evaporator was designed by twice vacuum filtration.Furthermore,through the arched design and the introduction of concentrated brine drainage system,the hydrogel evaporator has enhanced water transportation and tailored water transportation path.Such a unique drainage evaporation system greatly improves the stability of the evaporator.Thereby,a good balance is established between photothermal conversion and water supply,and solar energy is utilized efficiently.It can remain stable in continuous evaporation for up to 12 h with an excellent evaporation rate of 2.70 kg m^(-2)h^(-1)under 1 sun irradiation.Meanwhile,the drainage system realized the 1.8×10^(-10)mol m^(-2)s^(-1)diffusion flux of concentrated brine.Through one-time freeze-drying preparation,an arch-shaped drainage evaporator was used to prepare an evaporation area of more than 20 cm^(2).With the self-made condensate collecting device in outdoor environment,the fresh water yield reaches 7.5 L m^(-2)d^(-1).This provides a new scheme for building a new hydrogel evaporator and solving the fresh water crisis.
文摘Global freshwater scarcity and energy shortages demand integrated solutions.To overcome limitations of traditional solar evaporators,such as salt accumulation,thermal dissipation,and material scalability issues,this study presents a biomass-derived three-dimensional(3D)aerogel-based dual-function solar evaporator that simultaneously achieves ultra-high freshwater production and continuous electricity generation.By ingeniously integrating a superhydrophobic inner layer for thermal insulation and buoyancy with a hydrophilic photothermal outer layer for rapid water transport and solar absorption,our design overcomes the trade-offs between evaporation efficiency,salt resistance,and energy loss.The evaporator exhibits exceptional dual performance:an evaporation rate of 3.87 kg m^(-2)h-1(1 sun)and a sustained open-circuit voltage of 222.6 mV,surpassing most reported systems.This synergy originates from ion gradient-driven streaming potentials enabled by selective Na^(+) transport through–COOH/C–OH functionalized microchannels,as verified by molecular dynamics simulations.Crucially,the fabrication process utilizes low-cost biomass materials and scalable techniques,demonstrating significant potential for commercialization.This work not only provides a mechanistic understanding of ion-selective transport in dual-function evaporators but also establishes a paradigm for sustainable co-production of clean water and renewable energy,addressing two pressing global challenges through a single and scalable platform.
基金National Natural Science Foundation of China(No.51905089)Fundamental Research Funds for the Central Universities,China(No.2232020D-31)。
文摘The agitated thin-film evaporator(ATFE)plays a crucial role in evaporation and concentration processes.The design of the scraper for processing high-viscosity non-Newtonian fluids in the ATFE is complex.The intricate scraping action of the scraper introduces gas into the liquid film,leading to the formation of a gas ring along the wall.This process subsequently reduces wall heat flow,thereby affecting heat transfer.Computational fluid dynamics(CFD)is used to simulate the flow field of the non-Newtonian fluid in the ATFE.The investigation focuses on understanding the mechanism behind the formation of gas rings in the liquid film and proposes methods to prevent their formation.The results demonstrate a transition of the gas from a gas ring suspended in the liquid to a gas ring attached to the wall after entering the liquid film.The scraping action around the circumference of the scraper helps to expel gas rings,indicating the necessity of adjusting the scraper arrangement and increasing the frequency of scraping to enhance gas ring expulsion.The spiral motion of the bow wave serves as the source of gas entry into the liquid film.Therefore,the rotation speed can appropriately increase to reduce the size of the bow wave,thereby inhibiting the formation of the gas ring from the source.This research investigates the mechanism of gas ring generation and expulsion,offering theoretical guidance for processing high-viscosity non-Newtonian materials in the flow field of the ATFE.
基金supported by the Shandong Provincial Natural Science Foundation(ZR2023QE325).
文摘Frost accumulation on the evaporator fins of air source heat pumps(ASHPs)severely degrades heat transfer performance and overall system efficiency.To address this,the present study employs computational fluid dynamics(CFD)to investigate how fin spacing influences frosting behavior,emphasizing the coupled evolution of frost thickness,density,airflow,and temperature distribution within fin channels.Results reveal that fin spacing is a key parameter governing both the extent and rate of frost growth.Wider fin spacing enhances frost accumulation,with a final frost mass of 6.41 g at 12 mm,about 71.8%higher than at 4 mm.In contrast,narrower spacing suppresses frost formation by accelerating airflow.The frost layer exhibits a distinct two-stage growth pattern:at 12 mm spacing,the early-stage average thickness growth rate reaches 0.021 mm/min,nearly 4.3 times that at 4 mm.Frost density follows similar initial trends across different spacings but diverges later due to thermal resistance and airflow variations.
基金Science Foundation for Distinguished Young Scholars 2020-JCJQ-ZQ-042.
文摘The loop heat pipe with a flat evaporator is mainly divided into two forms:rectangular evaporator and disk-shaped evaporator.The rectangular evaporator has advantages such as low heat leakage,a thin shell,and a large contact area compared to the disk-shaped evaporator.However,most of the research on rectangular evaporators focuses onworking fluids such as water,methanol,and acetone,when theseworking fluids are in operation,the internal pressure of the evaporator is less than atmospheric pressure.Ammonia,propylene,and other working fluids can also be utilized in the loop heat pipe,these working fluids demonstrate better performance when operating within other temperature intervals,for example,the operating temperature range of ammonia is−20℃to 50℃,however,in an atmospheric pressure environment,it is very difficult for the shell of the rectangular evaporator to withstand the saturated vapor pressure of the working fluid.This paper designs a rectangular flat plate loop heat pipe that can use ammonia as the working fluid.The internal reinforcing structure is used to improve the pressure strength of the shell.The secondary wick connects the compensation chamber and the capillary wick hydraulically.The experiment indicates that this kind of rectangular evaporator is unaffected by the position,and the secondary wick can effectively supply liquid under different angles.The thermal resistance of the evaporator wall was analyzed,and it was found that the thermal resistance of the evaporator wall was the main component of the thermal resistance of the system.The heat transfer capacities of 460 W@0.5 m and 200W@10 m were tested.The test results indicate that by setting a reinforcing structure inside the flat plate evaporator,the evaporator can withstand internal pressure.Combined with the design of the secondary wick,the flat plate evaporator can use working fluids with different pressures,expanding the range of available working fluids.
