检索结果-内蒙古大学图书馆

Simultaneous Analysis of Liquid Film Instabilities and Properties of Swirl Sprays by Telecentric Shadowgraphy

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Machado, Danilo Almeida Costa, Fernando S. Dias, Gabriel Silva Mota, Fábio A.S. Combustion and Propulsion Laboratory National Institute for Space Research SP Cachoeira Paulista12630-000 Brazil State Key Laboratory of Multiphase Flows in Power Engineering Xi’an Jiaotong University Shanxi Xi’an710049 China

A telecentric shadowgraphy optical system was utilized to determine macroscopic and microscopic parameters of sprays and the measurement of conical liquid films formed by dual pressure swirl injectors. Spray cone angles, breakup lengths, mean droplet velocities, momentum flows, wave amplitude ratios and maximum wave growth rates were simultaneously measured using high-speed images with kHz frequencies. Two injectors were tested with inner nozzles having Abramovich geometric constants Kint = 2 and 2.125 and external nozzles with geometric constants Kext = 2.9 and 1.9792, respectively. Injection pressures were varied from 0.05 to 0.5 MPa and water was used as test fluid. The experimental data indicate that the breakup length, droplet velocity, flow momentum and disturbance amplitude ratio are higher for injectors with larger mass flow rates, for a given injection pressure. The maximum amplitude ratios of the conical liquid film disturbances varied in the range 2.32 © 2023, The Authors. All rights reserved.

关键词： Liquid films

Simultaneous Analysis of Swirl Spray Dynamics Using a Telecentric System

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Machado, Danilo Almeida de Souza Costa, Fernando Dias, Gabriel Silva Mota, Fábio A.S. Combustion and Propulsion Laboratory National Institute for Space Research SP Cachoeira Paulista12630-000 Brazil State Key Laboratory of Multiphase Flows in Power Engineering Xi’an Jiaotong University Shanxi Xi’an710049 China

关键词： Liquid films

Simultaneous Analysis of Liquid Film Instabilities and Properties of Swirl Sprays by Telecentric Shadowgraphy

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Machado, Danilo Almeida Costa, Fernando S. Dias, Gabriel Silva Mota, Fábio A.S. Combustion and Propulsion Laboratory National Space Research Institute SP Cachoeira Paulista12630-000 Brazil State Key Laboratory of Multiphase Flows in Power Engineering Xi’an Jiaotong University Shanxi Xi’an710049 China

A telecentric shadowgraphy optical system was utilized to determine macroscopic and microscopic parameters of sprays and the measurement of conical liquid films formed by dual pressure swirl injectors. Spray cone angles, breakup lengths, mean droplet velocities, momentum flows, wave amplitude ratios and maximum wave growth rates were simultaneously measured using high-speed images with kHz frequencies. Two injectors were tested with inner nozzles having Abramovich geometric constants Kint = 2 and 2.125 and external nozzles with geometric constants Kext = 2.9 and 1.9792, respectively. Injection pressures were varied from 0.05 to 0.5 MPa and water was used as test fluid. The experimental data indicate that the breakup length, droplet velocity, flow momentum and disturbance amplitude ratio are higher for injectors with larger mass flow rates, for a given injection pressure. On the other hand, the maximum wave growth rate of the liquid film is higher for injectors with smaller mass flow rates. The maximum amplitude ratios of the conical liquid film disturbances varied in the range 2.32 © 2023, The Authors. All rights reserved.

关键词： Liquid films

Evaluation on Hydrothermal Gasification of Styrene-Butadiene Rubber with Oxidants Via Reaxff-Md Simulation

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Nie, Shaoqiang Chen, Meiqian Li, Qinghai Institute of Thermal Engineering School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing100044 China Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale Beijing100044 China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power Engineering Tsinghua University Beijing100084 China

Styrene-butadiene rubber (SBR) is widely used in tires, which brings great challenge to the disposal and reclaiming of the used tires. The ring-opening reaction pathways of benzene rings in hydrothermal gasification of styrene-butadiene rubber were revealed based on reactive force field molecular dynamics (ReaxFF-MD) simulation. H-abstraction reaction that OH radicals capture H atom from the vinyl group of styrene was critical to degrade styrene monomers. The energy barrier of H2O2 converted to OH radicals was lower than that of O2 and pure water converted to OH radicals. The oxidants that can urge OH radical formed in reaction were beneficial to SBR degradation, which could be assigned to confirm that SBR degradation with H2O2 was better than that with oxygen at the same concentration. The addition of oxidant could be helpful for decreasing the degradation temperature of styrene monomers. At oxygen equivalent ratio (ER) of 0.1, H2 yield at 2500 K lifted after 135 ps and increased by 75% at 500 ps compared with that without oxidants. According to chemical equilibrium analysis, the optimal ER for H2 was 0.4 between 350-600 ºC (real temperatures). The results could provide theoretic support and experiment guidance for adding oxidants in reclaiming waste rubber products. © 2023, The Authors. All rights reserved.

关键词： Oxygen

Suppressing Condensation Frosting Using Micropatterned Ice Walls

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Zuo, Zichao Zhao, Yugang Li, Kang Zhang, Hua Yang, Chun Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering School of Energy and Power Engineering University of Shanghai for Science and Technology Shanghai200093 China Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development Center Sichuan Mianyang621000 China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore639798 Singapore

Condensation frosting is encountered ubiquitously in our daily life and numerous industrial applications, rooting many detrimental consequences in heat transfer and mechanical stabilities. In latest decades, both active de-frosting and passive anti-frosting methods have been developed. In this work, we adopt the concept of three-dimensional overlapping dry zones by patterning microscopic ice walls on a smooth substrate, engendering a sustainable frost coverage of less than 10%. Patterned ice walls prevent vapor deposition on the substrate base by absorbing all incoming moisture on upper sidewalls, leaving the substrate base free of contaminates from both frost and condensate. To ensure vapor preferentially depositing on upper sidewalls, a critical ice wall height exists, below which fine ice grains initiate in the adjacent of the substrate base and grow substantially faster, compromising the anti-frosting performance. The proposed surface shows reasonable durability when exposed to varying substrate supercooling, and frost coverage may increase due to covering and fracturing of the out-of-plane growth of feather-like ice clusters at large substrate supercooling. Our findings provide an effective anti-frosting surface design that doesn’t require any chemical or mechanical modifications on the targeted surfaces, showing great advantages compared to conventional icephobic surface designs. © 2022, The Authors. All rights reserved.

关键词： Ice

Hierarchical growth of a novel Mn-Bi coupled BiVO4 arrays for enhanced photoelectrochemical water splitting

学校读者我要写书评

暂无评论

Nano Research 2019年第3期12卷 575-580页

作者： Lu Wang Jinzhan Su Liejin Guo International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering School cf Energy & Power Engineering Xian Jiaotong University Xian 710049 China

Oxygen evolving catalyst (OEC) is a critical determinant for the efficiency of photoelectrochemical (PEC) water splitting. Here we report an approach to depositing a novel manganese borate (Mn-Bi) OER catalyst on BiVO4 nanocone photoanode by photodeposition in sodium borate buffer solution containing Mn(Ⅱ) ions. Due to the spontaneous photo-electric-field-enhancement effect at the vertically oriented BiVO4 nanocone structure, spherical Mn-Bi nanoparticle was selectively photodeposited at the apex of BiVO4 nanocone. Significant improvement of photocurrent was observed for the obtained hierarchical Mn-Bi/BiVO4 photoanode which could be ascribed to enhanced hole injection efficiency, especially in low bias region. It was observed that the injection efficiency of Mn-Bi/BiVO4 is 98% which gave a photocurrent of 0.94 mA/cm^2 at 1.5 V vs. RHE.

关键词： bismuth vanadate photoelectrochemistry solar water splitting oxygen evolution

Theoretical study on flow and radiation in tubular solar photocatalytic reactor

学校读者我要写书评

暂无评论

Frontiers in Energy 2021年第3期15卷 687-699页

作者： Qingyu WEI Yao WANG Bin DAI Yan YANG Haijun LIU Huaijie YUAN Dengwei JING Liang ZHAO International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Powering EngineeringXi’an Jiaotong UniversityXi’an 710049China Beijing Aerospace Propulsion Institute Beijing 100076China School of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai 200093China

In this paper,based on the mixture flow model,an optimized six-flux model is first established and applied to the tubular solar photocatalytic *** influencing photocatalyst distribution and radiation distribution at the reactor outlet,*** concentration and circulation speed,are also *** is found that,at the outlet of the reactor,the optimized six-flux model has better performances(the energy increase by 1900%and 284%,respectively)with a higher catalyst concentration(triple)and a lower speed(one third).

关键词： photocatalytic hydrogen photoreactor numerical simulation solar energy flow model radiation model

Zif-L(Co) Derived Cobalt Doped In2o3 Hollow Nanofibers with High Surface Activity for Efficient Formaldehyde Gas Sensing

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Zhu, Lei Wang, Jianan Liu, Jianwei Wang, Ze Sun, Shiyi Li, Mingtao Yan, Wei Xi’an Key Laboratory of Solid Waste Resource Regeneration and Recycling State Key Laboratory of Multiphase Flow Engineering Xi’an Jiaotong University Xi’an710049 China School of Physics and Electrical Engineering Weinan Normal University Chaoyang Street Weinan714099 China School of Chemistry and Chemical Engineering Xi’an University of Science & Technology Xi’an710054 China

Gas sensors based on semiconductor metal oxides are identified as a highly promising candidate for toxic gas detection, yet they still suffer from high operating temperature due to low surface activity at low temperature. To address this issue, we present an elaborate design for the homogeneous functionalization of ZIF-L(Co) derived cobalt (Co) catalysts into hollow In2O3 frameworks, aiming to highly activate the redox capacity and catalytic efficacy of the In2O3 sensor to HCHO gas. Benefiting from the Co catalysts doping boosts the catalytic activity and generates abundant oxygen vacancies, the optimized 1 wt% Co-doped In2O3 HNFs sensor exhibits a high response of 40.4 toward 100 ppm HCHO at a moderately low temperature of 180 ℃, which is 4 times higher than that of pristine In2O3 HNFs. Moreover, 1 wt% Co-doped In2O3 HNFs sensor has virtues of high selectivity and excellent long-term stability for HCHO sensing. This study highlights the important influence of Co catalyst on the modulation of surface active sites of metal oxides-based sensors, inspiring the development of cost-effective sensors for indoor hazardous gas monitoring. © 2023, The Authors. All rights reserved.

关键词： Cost effectiveness

Investigation of the Effect of Phosphate in Wastewater on the Electrochemical Performance of Cofe-Ldh@Ni Foam Adsorbents as Supercapacitor Electrode Materials

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Hong, Xianyong Shi, Mingxing Li, Jinghua Xia, Mingzhu Du, Ping Wang, Fengyun School of Chemistry and Chemical Engineering Nanjing University of Science and Technology Nanjing210094 China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China

Reducing P(V) in the environment is the key to solving the problem of eutrophication in water bodies. In this work, CoFe-LDH@NF composites were successfully prepared by a simple one-step hydrothermal method and efficiently obtained P(V) from wastewater. The P(V) in the phosphate undergoes a reduction reaction under a high temperature H2 atmosphere and reacts with the metal salt to form a metal phosphide (Co-Fe-P@NF). The electrochemical analysis shows that the reaction of P with metal elements to form the corresponding phosphide can effectively enhance the electrochemical properties of the composite. The specific capacitance of Co-Fe-P@NF is as high as 3.71 F/cm2 at a current density of 1 mA/cm2 and the specific capacitance retention rate is 81.7% after 2000 cycles of charging and discharging at a current density of 10 mA/cm2 . Furthermore, asymmetric supercapacitors (ASCs) were assembled with activated carbon (AC) as the negative electrode and Co-Fe-P@NF as the positive electrode with a voltage window of up to 1.6 V. Co-Fe-P@NF//AC ASC device allows the timer to operate generally for more than 75 mins. The excellent energy storage performance on the supercapacitor electrode material provides an effective solution for recycling the adsorbent. © 2022, The Authors. All rights reserved.

关键词： Supercapacitor