检索结果-南通市图书馆

Enhanced solid-electrolyte interface efficiency for practically viable hydrogen-air fuel cell systems

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 356-368页

作者： Venkitesan Sakthivel dong Jin Yoo Graduate School Department of Energy Storage/Conversion Engineering (BK21 FOUR) Hydrogen and Fuel Cell Research Center Jeonbuk National University Jeonju Department of Life Science Jeonbuk National University

Proton exchange membrane fuel cells （PEmFCs） provide an appealing sustainable energy system,with the solid-electrolyte membrane playing a crucial role in its overall ***,sulfonated poly（1,4-phenylene ether-ether sulfone）(SPEES),an aromatic hydrocarbon polymer,has garnered considerable attention as an alternative to Nafion ***,the long-term durability and stability of SPEES present a significant *** this context,we introduce a potential solution in the form of an additive,specifically a core–shell-based amine-functionalized iron titanate （A–Fe2TiO5）,which holds promise for improving the lifetime,proton conductivity,and power density of SPEES in *** modified SPEES/A–Fe2TiO5composite membranes exhibited notable characteristics,including high water uptake,enhanced thermomechanical stability,and oxidative ***,the SPEES membrane loaded with 1.2 wt%of A–Fe2TiO5demonstrates a maximum proton conductivity of 155 mS cm-1,a twofold increase compared to the SPEES membrane,at 80°C under 100%relative humidity （RH）.Furthermore,the 1.2 wt%of A–Fe2TiO5/SPEES composite membranes exhibited a maximum power density of 397.37 mW cm-2and a current density of 1148 mA cm-2at 60°C under 100%RH,with an opencircuit voltage decay of 0.05 m V/h during 103 h of continuous *** study offers significant insights into the development and understanding of innovative SPEES nanocomposite membranes for PEmFC applications.

关键词： Acid-base Hybrid membrane Proton conductivity Polymer electrolyte fuel cell Single-cell performance

Study on the Wiping Gas Jet in Continuous Galvanizing Line

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2011年第3期20卷 242-247页

作者： Yong-Hun kweon heuy-dong k.m POSCO Technical Research Laboratories 699 Gumho-dong GwangyangJeonnam 545-090 Korea School of mechanical Engineering Andong National UniversityAndong 760-749 Korea

In the continuous hot-dip galvanizing process, the gas-jet wiping is used to control the coating thickness of moving steel strip. The high speed gas-jet discharged from the nozzle slot impinges on the strip, and at this moment, wipes the liquid coating layer dragged by a moving strip. The coating thickness is generally influenced on the flow characteristics of wiping gas-jet such as the impinging pressure distribution, pressure gradient and shear stress distribution on the surface of strip. The flow characteristics of wiping gas-jet mentioned above depends upon considerably both the process operating conditions such as the nozzle pressure, nozzle-to-strip distance and line speed, and the geometry of gas-jet wiping apparatus such as the height of nozzle slot. In the present study, the effect of the geometry of nozzle on the coating thickness is investigated with the help of a computational fluid dynamics method. The height of nozzle slot is varied in the range of 0.6mm to 1.7mm. A finite volume method (FVm) is employed to solve two-dimensional, steady, compressible Navier-Stokes equations. Based upon the results obtained, the effect of the height of nozzle slot in the gas-jet wiping process is discussed in detail. The computational results show that for a given standoff distance between the nozzle to the strip, the effective height of nozzle slot exists in achieving thinner coating thickness.

关键词： Gas-Jet Wiping Hot-Dip Galvanizing Impact Pressure Coating Thickness

Numerical Simulation of Flow Characteristics in micro Shock Tubes

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2015年第3期24卷 246-253页

作者： Guang Zhang Toshiaki Setoguchi heuy dong k.m Department of mechanical Engineering Andong National University Department of mechanical Engineering Saga University

Recently micro shock tubes have been widely used in many engineering and industrial fields, but the characteristics of unsteady flow are not well known to date in micro shock tubes. Compared to conventional shock tubes with macro scales, flows related to shock waves in micro shock tubes are highly complicated. Stronger viscous and dissipative interactions make shock wave dynamic behaviors significantly different from theoretical predictions. In the present study, a CFD work was applied to the unsteady compressible Navier-Stokes equations which were solved using a fully implicit finite volume scheme. The diaphragm pressure ratio and shock tube diameter were varied to investigate their effects on micro shock tube flows. Different wall boundary conditions were also performed to observe shock wave and contact surface propagation with no slip and slip walls. Detailed flow characteristics at the foot of shock wave and contact surface propagation were known from the present numerical simulations.

关键词： micro shock tube Shock wave propagation Slip wall Unsteady flow CFD

Computational Study of Performance Characteristics for Truncated Conical Aerospike Nozzles

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2017年第6期26卷 483-489页

作者： Prasanth P Nair Abhilash Suryan heuy dong k.m Department of mechanical Engineering College of Engineering Trivandrum Department of mechanical Engineering Andong National University

Aerospike nozzles are advanced rocket nozzles that can maintain its aerodynamic efficiency over a wide range of altitudes. It belongs to class of altitude compensating nozzles. A vehicle with an aerospike nozzle uses less fuel at low altitudes due to its altitude adaptability, where most missions have the greatest need for thrust. Aerospike nozzles are better suited to Single Stage to Orbit （SSTO） missions compared to conventional nozzles. In the cur- rent study, the flow through 20% and 40% aerospike nozzle is analyzed in detail using computational fluid dy- namics technique. Steady state analysis with implicit formulation is carried out. Reynolds averaged Navier-Stokes equations are solved with the Spalart-AUmaras turbulence model. The results are compared with experimental results from previous work. The transition from open wake to closed wake happens in lower Nozzle Pressure Ratio for 20% as compared to 40% aerospike nozzle.

关键词： aerospike nozzle plug nozzle advanced rocket nozzles thrust coefficient base pressure.

Experimental Study on the Inlet Fogging System Using Two-Fluid Nozzles

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2010年第2期19卷 132-135页

作者： Abhilash Suryan dong Sun k.m heuy dong k.m School of mechanical Engineering Andong National University FmTRC Daejoo Machinery Co.

Large-capacity compressors in industrial plants and the compressors in gas turbine engines consume a considerable amount of power. The compression work is a strong fimction of the ambient air temperature. This increase in compression work presents a significant problem to utilities, generators and power producers when electric demands are high during the hot months. In many petrochemical process industries and gas turbine engines, the in- crease in compression work curtails plant output, demanding more electric power to drive the system. One way to counter this problem is to directly cool the inlet air. Inlet fogging is a popular means of cooling the inlet air to air compressors. In the present study, experiments have been performed to investigate the suitability of two-fluid nozzle for inlet fogging. Compressed air is used as the driving working gas for two-fluid nozzle and water at am- bient conditions is dragged into the high-speed air jet, thus enabling the entrained water to be atomized in a very short distance from the exit of the two-fluid nozzle. The air supply pressure is varied between 2.0 and 5.0 bar and the water flow rate entrained is measured. The flow visualization and temperature and relative humidity measurements are carried out to specify the fogging characteristics of the two-fluid nozzle.

关键词： Evaporative Cooling Inlet Fogging Energy Savings Two-fluid Nozzles

Supersonic Cavity Based Combustion with kerosene/Hydrogen Fuel

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2015年第2期24卷 164-172页

作者： Rajarshi Das Jeong Soo k.m heuy dong k.m Department of mechanical Engineering Andong National University School of mechanical Engineering Pukyong National University

A comparative study with kerosene and hydrogen fuel in a model scramjet combustor has been carried out nu- merically. The effect of fuel-air equivalence ratio on the flow field properties in a cavity based mixing mechanism at a freestream math number of 2.08 has been probed. The investigation has been carried out in a two dimension- al numerical model where a cavity of length to depth ratio of 2 is mounted on one of the walls of the flow channel The flow field shock structure is observed to change with the change in fuel-air equivalence ratio. Total pressure loss is observed to depend both on fuel air equivalence ratio and the fuel type. The spread of fuel in the test sec- tion shows marked variation with the equivalence ratio. Performance of injector location on the fuel-air mixing is also probed during the course of the investigation.

关键词： Scramjet fuel-air mixing kerosene hydrogen equivalence ratio

Low-temperature chlorination roasting technology for the simultaneous recovery of valuable metals from spent LiCoO_(2)cathode material

在线全文

学校读者我要写书评

暂无评论

International Journal of minerals,metallurgy and materials 2025年第1期32卷 80-91页

作者： Junjie Shi Changle Hou Jingjing dong dong Chen Jianzhong Li key Laboratory for Ecological metallurgy of multimetallic mineral(ministry of Education) Northeastern UniversityShenyang 110819China School of metallurgy Northeastern UniversityShenyang 110819China

With the continuous increase in the disposal volume of spent lithium-ion batteries(LIBs),properly recycling spent LIBs has become essential for the advancement of the circular *** study presents a systematic analysis of the chlorination roasting kinetics and proposes a new two-step chlorination roasting process that integrates thermodynamics for the recycling of LIB cathode *** activation energy for the chloride reaction was 88.41 kJ/mol according to thermogravimetric analysis–derivative thermogravimetry data obtained by using model-free,model-fitting,and Z(α)function(αis conversion rate).Results indicated that the reaction was dominated by the first-order(F1)model when the conversion rate was less than or equal to 0.5 and shifted to the second-order(F2)model when the conversion rate exceeded *** conditions were determined by thoroughly investigating the effects of roasting temperature,roasting time,and the mass ratio of NH_(4)Cl to LiCoO_(2).Under the optimal conditions,namely 400℃,20 min,and NH_(4)Cl/LiCoO_(2)mass ratio of 3:1,the leaching efficiency of Li and Co reached 99.43% and 99.05%,*** of the roasted products revealed that valuable metals in LiCoO_(2)transformed into CoCl_(2) and ***,the reaction mechanism was elucidated,providing insights for the establishment of a novel low-temperature chlorination roasting technology based on a crystal structure *** technology can guide the development of LIB recycling processes with low energy consumption,low secondary pollution,high recovery efficiency,and high added value.

关键词： spent lithium-ion battery thermodynamics chlorination roasting kinetics circular economy

The Effect of Diffuser Angle on the Discharge Coefficient of a miniature Critical Nozzle

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2010年第3期19卷 222-227页

作者： Jae Hyung k.m heuy dong k.m Toshiaki Setoguchi School of mechanical Engineering Andong National UniversityAndong760-749Korea Department of mechanical Engineering Saga University1HonjoSagaJapan

many researches on critical nozzles have been performed to accurately measure the mass flow rate of gas flow,and to standardize the performance as a flow ***,much interest is being paid on the measurement of very small mass flow rate in industry fields such as mEmS ***,the design and performance data of the critical nozzles obtained so far have been applied mainly to the critical nozzles with comparatively large diameters,and the works available on miniature critical nozzles are *** the present study,a computational fluid dynamics method has been applied to investigate the influence of the diffuser angle on discharge coefficient of the miniature critical *** computations,the throat diameter of critical nozzle is varied from 0.2 mm to 5.0 mm and the diffuser angle is changed from 2 deg to 8 *** computational results are validated with some experimental data *** results show that the present computational results predict appropriately the discharge coefficient of the gas flows through miniature critical *** is known that the discharge coefficient is considerably influenced by the diffuser angle,as the throat diameter of nozzle becomes small below a certain *** implies that the miniature critical nozzles should be carefully designed.

关键词： Compressible Flow Critical Nozzle Compressible Flow Discharge Coefficient Diffuser Configuration Reynolds Number

Transonic moist Air Flow around a Circular Arc Blade with Bump

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2009年第4期18卷 325-331页

作者： A.B.m.Toufique HASAN Shigeru mATSUO Toshiaki SETOGUCHI heuy dong k.m Department of mechanical Engineering Bangladesh University of Engineering and Technology Department of mechanical Engineering Saga University School of mechanical Engineering Andong National University

The unsteady phenomena in the transonic flow around airfoils are observed in the flow field of fan, compressor blades and butterfly valves, and this causes often serious problems such as aeroacoustic noise and the vibration. In recent years, the effect of bump wall on the flow field around an airfoil has been investigated experimentally and as a result, it was observed that the bump wall is effective for the control of shock wave on the airfoil. In the transonic or supersonic flow field, a rapid expansion of moist air or steam gives rise to non-equilibrium condensation. In the present study, the effect of non-equilibrium condensation of moist air on the self-excited shock wave oscillation around a circular arc blade with or without a bump on the blade was investigated numerically. The results showed that the non-equilibrium condensation significantly reduced the flow field unsteadiness such as root mean of pressure oscillation and frequency compared to the case without the non-equilibrium condensation.

关键词： transonic flow moist air shock wave oscillation non-equilibrium condensation