Stefan flow induced natural convection suppression on high-flux evaporators

Zhang, Lenan; Zhao, Lin; Wang, Evelyn N.

doi:10.1016/j.icheatmasstransfer.2019.03.020

Cited by 9 publications

(7 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This evaporative heat transfer coefficient was calibrated from experiments. An additional heat transfer coefficient h natutral = 5 W m −2 K −1 was also applied to the water-air interface to quantify the heat loss due to natural convection 45 .…”

Section: Salt Transport Modelingmentioning

confidence: 99%

Highly efficient and salt rejecting solar evaporation via a wick-free confined water layer

et al. 2022

Self Cite

View full text Add to dashboard Cite

Recent advances in thermally localized solar evaporation hold significant promise for vapor generation, seawater desalination, wastewater treatment, and medical sterilization. However, salt accumulation is one of the key bottlenecks for reliable adoption. Here, we demonstrate highly efficient (>80% solar-to-vapor conversion efficiency) and salt rejecting (20 weight % salinity) solar evaporation by engineering the fluidic flow in a wick-free confined water layer. With mechanistic modeling and experimental characterization of salt transport, we show that natural convection can be triggered in the confined water. More notably, there exists a regime enabling simultaneous thermal localization and salt rejection, i.e., natural convection significantly accelerates salt rejection while inducing negligible additional heat loss. Furthermore, we show the broad applicability by integrating this confined water layer with a recently developed contactless solar evaporator and report an improved efficiency. This work elucidates the fundamentals of salt transport and offers a low-cost strategy for high-performance solar evaporation.

show abstract

Section: Salt Transport Modelingmentioning

confidence: 99%

Highly efficient and salt rejecting solar evaporation via a wick-free confined water layer

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…Realizing solar-vapor conversion efficiency > 90% requires not only an ultralow (e.g., ≈ 5 -10 W m -2 ℎ K -1 ) but also a relatively low (e.g., ≈ 5 -15 ℃) which is challenging, especially considering Δ the fact that convective heat loss coefficient is already 5 -15 W m -2 K -1 in a quiescent ℎ 11 ambient air. [72][73][74] The most effective path to optimize evaporator performance should be along the trajectory A-B in Fig. 3a where and are reduced simultaneously.…”

Section: Factors Limiting Evaporator Performancementioning

confidence: 99%

“…Similar to most studies on evaporator design, we consider an evaporator as an open system, i.e., vapor transport is from the evaporator to the far-field air ambient. [72][73][74][75][76] According to the energy balance, the total input solar energy (units: W) is converted into thermal energy driving evaporation and heat loss ,…”

Section: δ ℎmentioning

confidence: 99%

Passive, high-efficiency thermally-localized solar desalination

Zhang

Zhao

et al. 2021

Energy Environ. Sci.

Self Cite

209

114

View full text Add to dashboard Cite

show abstract

“…Although high-temperature solar steam generation has been demonstrated in recent studies, their solar-to-steam conversion efficiency is limited (z 20%) due to higher heat losses at elevated temperatures (>100 C). [19][20][21][22] Therefore, new strategies are required to enable efficient solar steam generation processes at high temperatures.…”

Section: Context and Scalementioning

confidence: 99%

A Passive High-Temperature High-Pressure Solar Steam Generator for Medical Sterilization

Zhao

Bhatia

Zhang

et al. 2020

Joule

Self Cite

View full text Add to dashboard Cite

Solar steam generation at the sterilization condition suffers from low efficiency, especially in passive solar thermal devices. We developed a stationary solar collector with a transparent aerogel layer to achieve efficient solar steam generation via thermal concentration. In field tests performed in Mumbai, India, the device generated steam at 100 C with 56% efficiency and successfully powered a sterilization cycle following the standard sterilization protocol. Our work shows the potential of solar thermal technology in steam generation and other applications.

show abstract

Stefan flow induced natural convection suppression on high-flux evaporators

Cited by 9 publications

References 32 publications

Highly efficient and salt rejecting solar evaporation via a wick-free confined water layer

Highly efficient and salt rejecting solar evaporation via a wick-free confined water layer

Passive, high-efficiency thermally-localized solar desalination

A Passive High-Temperature High-Pressure Solar Steam Generator for Medical Sterilization

Contact Info

Product

Resources

About