In this study,the flow pattern and bubble behavior of R1233zd(E)during subcooled flow boiling in parallel channels are experimentally investigated with visualization and thermal *** test section is composed of 21 rect...
详细信息
In this study,the flow pattern and bubble behavior of R1233zd(E)during subcooled flow boiling in parallel channels are experimentally investigated with visualization and thermal *** test section is composed of 21 rectangular mini channels with the hydraulic diameter of 1.5 mm and the length of 140 *** flow,slug flow,churn flow and wavy-annular flow occur in sequence with the increase of vapor quality,while transient flow pattern transition process involving multiple flow patterns are also *** distribution of flow pattern is non-synchronized and axial-asymmetric,with earlier flow pattern transitions observed in peripheral channels away from the center *** initial nucleate site in each channel also show a random and axial-asymmetric distribution,while faster bubble growth can be noted in some channel under the comprehensive effects of liquid evaporation and bubble *** variation of heat transfer coefficient is correspondence to the flow pattern transition,showing different trends along the flow *** increase of mass flux can lead to delayed flow pattern transition and variation of heat transfer *** addition,higher heat transfer coefficient can be noted in channels away from the center axis.
Refrigerant flash spray cooling, which offers high heat flux dissipation at low temperatures, holds significant potential for thermal management of high-power electronic devices. While surface structure design can fur...
详细信息
Electrocatalysts with optimal efficiency and durability for the oxygen evolution reaction(OER)are becoming increasingly important as the demand for alkaline water/seawater electrolysis technology ***,a novel rose-shap...
详细信息
Electrocatalysts with optimal efficiency and durability for the oxygen evolution reaction(OER)are becoming increasingly important as the demand for alkaline water/seawater electrolysis technology ***,a novel rose-shaped NiFe-layered double hydroxide(LDH)/NiCo_(2)O_(4)composed of amorphous wrinkled NiFe-LDH and highly crystalline NiCo_(2)O_(4)was synthesized with rich *** unsaturated metal sites are generated due to significant charge reconstruction at the heterointerface between the crystalline and amorphous *** metal sites could trigger and provide more active *** density functional theory(DFT)reveals that a new charge transfer channel(Co-Fe)was formed at the heterointerface between NiFe-LDH as electron acceptor and NiCo_(2)O_(4)as electron *** new charge transfer channel boosts interfacial charge transfer and enhances catalytic *** NiFe-LDH/NiCo_(2)O_(4)/nickel foam(NF)drives current densities of 10 and 100 mA·cm−2 with overpotentials of 193 and 236 mV,*** composite electrode demonstrates a fast turnover frequency(0.0143 s−1)at 1.45 V ***(RHE=reversible hydrogen electrode),which is 5.5 times greater than pure NiCo_(2)O_(4),suggesting its superior intrinsic ***,NiFe-LDH/NiCo_(2)O_(4)/NF electrode exhibited negligible degradation after 150 h of uninterrupted running in alkaline seawater *** study introduces a method for preparing high-efficiency electrocatalysts utilized in alkaline water/seawater electrolysis.
The high penetration of renewable energy introduces increased volatility into the power system, presenting more challenging peak shaving and frequency modulation missions for thermal power plants that serve as schedul...
详细信息
Supercritical water fluidized bed(SCWFB)reactors are designed to gasify biomass or coal with high *** this paper,the wall-to-bed heat transfer characteristics in SCWFB are studied using the computational fluid dynamic...
详细信息
Supercritical water fluidized bed(SCWFB)reactors are designed to gasify biomass or coal with high *** this paper,the wall-to-bed heat transfer characteristics in SCWFB are studied using the computational fluid dynamics and discrete element method(CFD-DEM)coupled with a constant heat flux *** different methods are considered to deal with the multiphase heat flux boundary in CFD-DEM because there is currently no single widely accepted ***’s method predicts a more accurate wall-to-bed heat transfer coefficient in SCWFB than Lattanzi’s method according to comparisons of the simulation results with an empirical *** influences of temperature,pressure,velocity,and the solid phase properties,such as the particle diameter,particle heat capacity,particle thermal conductivity,and particle density,on the SCWFB wall-to-bed heat transfer characteristics are studied based on Zhang’s *** simulation results help reveal the SCWFB heat transfer characteristics.
Here,a metal-organic framework(MOF)-templated strategy was applied to synthesize the CoCeO_(x) bimetallic catalysts by calcining Co partially-substituted *** is indicated that the substituted Co limited Ce cations in ...
详细信息
Here,a metal-organic framework(MOF)-templated strategy was applied to synthesize the CoCeO_(x) bimetallic catalysts by calcining Co partially-substituted *** is indicated that the substituted Co limited Ce cations in Ce-UiO-66 framework,which affects its growth and structure crystallinity to some *** pyrolysis treatment,the derived bimetallic oxide(CoCeO_(x)-M)can basically keep the octahedral structure and the surface area is much higher than the bulk metal composite oxide(CoCeO_(x)-B)prepared by traditional *** reveal that CoCeO_(x)-M performs the best chlorobenzene degradation capacity,superior stability and vapor tolerance compared with those of CeO_(2)-M(derived from Ce-UiO-66)and CoCeO_(x)-*** the same time,it is favorable to inhibit the formation of CO during the oxidation *** superior catalytic performance of CoCeO_(x)-M is attributed to a good dispersion of metal cations,high surface area and active oxygen concentration,and good redox ***,the formation of organic byproducts especially chlorinated organics can be obviously prohibited over CoCeO_(x)-M compared with that of CeO_(2)-*** study reveals that chlorobenzene dissociates on the surface of CoCeO_(x)-M to form carboxylates such as acetate species,maleate and phenolate before finally oxidized into CO_(2),H_(2)O,and *** present work poses new insights into the fabrication of efficient catalysts for industrial CVOC purification.
t A series of inline pico hydropower systems,which could be used in confined space,especially for water distribution networks(WDNs),was designed and *** turbine with an eye-shaped vertical water baffle was developed t...
详细信息
t A series of inline pico hydropower systems,which could be used in confined space,especially for water distribution networks(WDNs),was designed and *** turbine with an eye-shaped vertical water baffle was developed to evaluate the hydraulic performance.A three-dimensional dynamic mesh was employed and the inlet velocity was considered as the inlet boundary condition,whereas the outlet boundary was set as the ***,numerical simulations were conducted and the standard k-εturbulence model was found to be the best capable of predicting flow features through the comparison with the experimental *** effects of the opening diameter of the water baffle and installation angle of the rotor on the flow field in the turbine were *** results suggested that the water baffle opening at d=30 mm and the rotor at a 52°angle could achieve the highest efficiency of 5.93%.The proper eye-shaped baffle not only accelerates the fluid flow and generates positive hydrodynamic torque,but also eliminates the flow *** scheme proposed in this paper can be exploited for practical applications in the water pipelines at various conditions and power requirements.
Plasmonic nanomaterial catalysis is currently at the frontier of photocatalysis,overcoming the limitations of wide bandgap semiconductors for light *** localized surface plasmon resonance(LSPR)properties allow broad u...
详细信息
Plasmonic nanomaterial catalysis is currently at the frontier of photocatalysis,overcoming the limitations of wide bandgap semiconductors for light *** localized surface plasmon resonance(LSPR)properties allow broad ultraviolet-visible-near infrared ray(UV-vis-NIR)absorption,making it an ideal material for solar energy *** plasmonic nanostructures rely on precious *** noble metal plasmonic nanomaterials have proven to be one of the strategies for enhancing photocatalytic activity,their expensive cost and limitations in light absorption range have hindered their practical *** a result,noble-metal free plasmonic nanomaterials have risen to the top of the research priority ***,this paper reviews the fundamental principles and classification of the LSPR effect of noble-metal free plasmonic nanomaterials in photocatalytic and their recent applications in hydrogen generation,carbon dioxide reduction,and pollutant *** cases elucidate the possible working mechanism of enhanced photocatalysis by noble-metal free plasmonic ***,the challenges and future opportunities for noble-metal free plasmonic nanomaterials in energy conversion and storage are discussed and envisioned.
Coal consumption leads to over 15 billion tons of global CO_(2) emissions annually,which will continue at a considerable intensity in the foreseeable *** remove the huge amount of CO_(2),a practically feasible way of ...
详细信息
Coal consumption leads to over 15 billion tons of global CO_(2) emissions annually,which will continue at a considerable intensity in the foreseeable *** remove the huge amount of CO_(2),a practically feasible way of direct carbon mitigation,instead of capturing that from dilute tail gases,should be developed;as intended,we developed two innovative supporting technologies,of which the status,strengths,applications,and perspective are discussed in this *** is supercritical water gasification-based coal/biomass utilization technology,which orderly converts chemical energy of coal and low-grade heat into hydrogen energy,and can achieve poly-generation of steam,heat,hydrogen,power,pure CO_(2),and *** other one is the renewables-powered CO_(2) reduction techniques,which uses CO_(2) as the resource for carbon-based fuel *** combining the above two technical loops,one can achieve a full resource utilization and zero CO_(2) emission,making it a practically feasible way for China and global countries to achieve carbon neutrality while creating substantial domestic benefits of economic growth,competitiveness,well-beings,and new industries.
The problem of droplets impacting rough wall has always been a hot spot in the engineering field. In this paper, the single-component multiphase lattice Boltzmann method is used to construct the wall microstructure, a...
详细信息
暂无评论