The optimal design of solid-state hydrogen storage devices is crucial for their effectiveness. This study investigates the thermal management of LaNi 5 -based metal hydride reactors for solid-state hydrogen storage by...
The optimal design of solid-state hydrogen storage devices is crucial for their effectiveness. This study investigates the thermal management of LaNi 5 -based metal hydride reactors for solid-state hydrogen storage by incorporating various fin materials: copper, aluminum nitride (AlN), and Aluminum Silicon Magnesium (AlSi10Mg). Utilizing ANSYS FLUENT 15.0 for simulations within a 2D numerical model, User-Defined Functions (UDFs) were employed to access the dehydrogenation process over a half-hour period. The reactor is subjected to an initial temperature of 363 K and heating oil is introduced at a speed of 1 m/s pressures ranging from 1 to 2 bar. The impact of different fin materials on enhancing the reactor's desorption properties was evaluated through key metrics such as hydrogen concentration, forced convection heat transfer coefficient, and average reactor temperature. Results demonstrate a remarkable improvement in hydrogen desorption rates, where copper fins achieve up to 67.6 % reduction in time to reach equilibrium at 1 bar compared to the reactor without fins. Similarly, AlN and AlSi10Mg fins exhibit a 64 % and 62 % reduction, respectively, highlighting their contributions to improved reactor performance. This research contributes to the advancement of hydrogen storage technologies by offering insights into the selection of fin materials and design for efficient.
Slug flow is one of the commonly encountered liquid and gas two-phase flow patterns. The accurate prediction of its behaviours is crucial for practical engineering applications. Liquid viscosity and pipe diameter are ...
详细信息
Based on the existing energy-minimization multi-scale(EMMS)model for turbulent flow in pipe,an improved version is proposed,in which not only a new radial velocity distribution is introduced but also the quantificatio...
详细信息
Based on the existing energy-minimization multi-scale(EMMS)model for turbulent flow in pipe,an improved version is proposed,in which not only a new radial velocity distribution is introduced but also the quantification of total dissipation over the cross-section of pipe is improved for the dominant mechanism of fully turbulent flow in *** four dynamic equality constraints and some other constraints are constructed but there are five parameters involved,leading to one free variable *** the compromise in competition between dominant mechanisms for laminar and fully turbulent flow in pipe respectively,the above four constructed dynamic equality constraints can be ***,the cases for turbulent flow in pipe with low,moderate and high Reynolds number are simulated by the improved EMMS *** numerical results show that the model can obtain reasonable results which agree well with the data computed by the direct numerical simulation and those obtained by *** illustrates that the improved EMMS model for turbulent flow in pipe is reasonable and the compromise in competition between dominant mechanisms is indeed a universal governing principle hidden in complex ***,one more EMMS model for a complex system is offered,pro-moting the further development of mesoscience.
This study investigates the integration of an amine-based CO2 capture system with a municipal solid waste incineration (MSWI) plant in Germany, focusing on mitigating CO2 emissions from flue gas. Using operational dat...
详细信息
In this work, a Cu/Fe2O3@g-C3N4 nanocomposite was synthesed using the thermal decomposition of urea as a carbon and nitrogen precursor to remove the reactive blue 19 (RB-19) in aqueous solution by the Fenton process. ...
详细信息
The principal cause of reverse osmosis (RO) system failures is membrane fouling, which results from the accumulation of water-formed or water-borne deposits that impede the flow of fluid and increase the pressure diff...
详细信息
The principal cause of reverse osmosis (RO) system failures is membrane fouling, which results from the accumulation of water-formed or water-borne deposits that impede the flow of fluid and increase the pressure differential across a membrane. Anti-scalant chemicals have been used for many years in RO units to minimize fouling, prevent scaling, and improve RO plant performance. The conventional method for controlling scale formation on membranes involves addition of sulfuric acid and a scale inhibitor to the feed water. However, the desire for improved chemical treatment programs to prevent scaling and fouling in RO units brought Saudi Aramco and Specialty Chemical Suppliers together. The challenge to produce a chemical treatment program that was simpler, safer, and more economical than the traditional sulfuric acid treatment and a scale inhibitor was identified as a mutual goal. This paper presents the results of intensive trials conducted by Saudi Aramco and the chemical suppliers to evaluate commercially available chemical formulations.
Hierarchically ordered macro-mesoporous TiO2 films (Ti-Ma-Me) were fabricated on fluorine-doped tin oxide (FTO) substrates through the confinement self-assembly method. The prepared Ti-Ma-Me possesses periodically ord...
详细信息
Hierarchically ordered macro-mesoporous TiO2 films (Ti-Ma-Me) were fabricated on fluorine-doped tin oxide (FTO) substrates through the confinement self-assembly method. The prepared Ti-Ma-Me possesses periodically ordered structure and a large specific surface area, which was applied as an interfacial layer between the nanocrystalline TiO2 film (P25-TiO2) and FTO electrode in the dye-sensitized solar cell (DSSC). The introduction of a Ti-Ma-Me interfacial layer increased the shortcircuit current density (Jsc) from 7.49 to 10.65 mA/cm2 and the open-circuit voltage (Voc) from 0.65 to 0.70 V as the result of its improved light harvesting efficiency by allowing for the high roughness factor and enhanced multiple internal reflection or scattering as well as reducing the back-transport reaction by blocking direct contact between the electrolyte and FTO electrode. Therefore, the photovoltaic conversion efficiency (η) was improved by 83% from 3.04% to 5.55%, as compared to a device using a bare P25 TiO2 photoanode.
A four step method is presented for the formal specification and synthesis of procedural controllers. These controllers are used in the process industries for safety and alarm operations, interlocking, batch sequencin...
详细信息
A four step method is presented for the formal specification and synthesis of procedural controllers. These controllers are used in the process industries for safety and alarm operations, interlocking, batch sequencing, etc. The procedural controller is based on a process model that takes the form of a labelled finite state machine, termed a-machine. Desired process behaviour specifications are constructed using Predicate (PL) and Linear Temporal Logic (LTL) formalisms. The resulting controller structure can then be translated into a target sequential control language for implementation. The method is demonstrated with a small example.
Ionic liquids(ILs)have attracted intensive attention and have been used widely in many applications because of their diversified properties,which are caused by the special structure of the *** clusters are one of the ...
详细信息
Ionic liquids(ILs)have attracted intensive attention and have been used widely in many applications because of their diversified properties,which are caused by the special structure of the *** clusters are one of the typical structures that exist widely in the IL *** are stable under certain conditions and change under other *** clusters are a typical mesoscale phenomenon in *** this review,we summarize our recent progress related to ionic clusters,including the ionic-cluster structure,changing mechanisms,and their effect on the physicochemical *** cluster investigation based on mesoscience is very important,will provide new insight into the structures and properties of ILs,and will boost further exploration of IL applications.
The residence time distribution (RTD) of solids and the fluidized structure of a bubbling fluidized bed were investigated numerically using computational fluid dynamics simulations coupled with the modified structur...
详细信息
The residence time distribution (RTD) of solids and the fluidized structure of a bubbling fluidized bed were investigated numerically using computational fluid dynamics simulations coupled with the modified structure-based drag model. A general comparison of the simulated results with theoretical values shows reasonable agreement. As the mean residence time is increased, the RTD initial peak intensity decreases and the RTD curve tail extends farther. Numerous small peaks on the RTD curve are induced by the back- mixing and aggregation of particles, which attests to the non-uniform flow structure of the bubbling fluidized bed. The low value of t50 results in poor contact between phases, and the complete exit age of the overflow particles is much longer for back-mixed solids and those caught in dead regions. The formation of a gulf-stream flow and back-mixing for solids induces an even wider spread of RTD.
暂无评论