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Articles 1 - 27 of 27
Full-Text Articles in Engineering
Reduced-Order Dynamic Modeling And Robust Nonlinear Control Of Fluid Flow Velocity Fields, Anu Kossery Jayaprakash, William Mackunis, Vladimir Golubev, Oksana Stalnov
Reduced-Order Dynamic Modeling And Robust Nonlinear Control Of Fluid Flow Velocity Fields, Anu Kossery Jayaprakash, William Mackunis, Vladimir Golubev, Oksana Stalnov
Publications
A robust nonlinear control method is developed for fluid flow velocity tracking, which formally addresses the inherent challenges in practical implementation of closed-loop active flow control systems. A key challenge being addressed here is flow control design to compensate for model parameter variations that can arise from actuator perturbations. The control design is based on a detailed reduced-order model of the actuated flow dynamics, which is rigorously derived to incorporate the inherent time-varying uncertainty in the both the model parameters and the actuator dynamics. To the best of the authors’ knowledge, this is the first robust nonlinear closed-loop active flow …
Coupling Simulation Of Groundwater Dynamics And Solute Transfer In The Process Of Deep Reinjection Of Mine Water, Zhao Chunhu, Yang Jian, Wang Shidong, Zhou Jianjun, Xu Feng, Liu Ji
Coupling Simulation Of Groundwater Dynamics And Solute Transfer In The Process Of Deep Reinjection Of Mine Water, Zhao Chunhu, Yang Jian, Wang Shidong, Zhou Jianjun, Xu Feng, Liu Ji
Coal Geology & Exploration
The deep well reinjection of mine water is a main form of "transfer storage" treatment of mine water. According to the geological and mine water characteristics of the coal mine area in Ordos Basin, the paper puts forward the basis for selecting the target layer of mine water reinjection from the perspective of good matching between groundwater and mine water in the target layer of reinjection, the water isolation of upper and lower strata, permeability and sealing of the reinjection layer. Based on Darcy's law of groundwater and Dupuit's theory, a mathematical model of steady flow of water injection well …
Simple, Cost-Effective Fabrication, And Flow Dynamics Analysis Of A Passive Microfluidic Mixer Using 3d Printing And Soft Lithography, Md Fazlay Rubby, Mohammad Salman Parvez, Nazmul Islam
Simple, Cost-Effective Fabrication, And Flow Dynamics Analysis Of A Passive Microfluidic Mixer Using 3d Printing And Soft Lithography, Md Fazlay Rubby, Mohammad Salman Parvez, Nazmul Islam
Electrical and Computer Engineering Faculty Publications and Presentations
Simple and low-cost fabrication of microfluidic devices has attracted considerable attention among researchers. The traditional soft lithography fabrication method requires expensive equipment like a UV exposure system and mask fabrication facility. In this work, an alternative and low-cost UV exposure system was introduced along with an alternative mask fabrication system. A previously reported passive microfluidic mixer was fabricated successfully using this modified soft lithography method. Challenges were presented during this modified fabrication method. Another emerging potential alternative for the fabrication of microfluidic mixers is 3D printing. It was also used in this experiment to fabricate a passive micromixer. This method …
Editorial: Development And Application Of Bituminous Materials For Civil Infrastructures, Zhanping You, Jie Ji, Dawei Wang, Feng Li, Hui Yao, Yue Hou
Editorial: Development And Application Of Bituminous Materials For Civil Infrastructures, Zhanping You, Jie Ji, Dawei Wang, Feng Li, Hui Yao, Yue Hou
Michigan Tech Publications
No abstract provided.
Effect Of Deposition Conditions On Properties Of Molybdenum Back Electrode For Cu(In,Ga)Se2 Solar Cell And Cu(In,Ga)Se2 Performance Analysis Through Numerical Simulation, Meah Imtiaz Zulkarnain
Effect Of Deposition Conditions On Properties Of Molybdenum Back Electrode For Cu(In,Ga)Se2 Solar Cell And Cu(In,Ga)Se2 Performance Analysis Through Numerical Simulation, Meah Imtiaz Zulkarnain
Theses and Dissertations
In the first part of this research, the effect of the deposition conditions on properties of molybdenum thin-film were investigated to achieve desired characteristics for its application as the back electrode of Cu(In,Ga)Se2 solar cell. DC and RF magnetron sputtering modes were employed and two sputtering parameters namely, working pressure and sputtering power, were varied to determine the sputtering mode and the sputtering conditions best suited for Mo thin-films having required properties. Sputtered Mo samples were characterized to determine their structural and mechanical properties such as preferred growth orientation, crystallinity, grain size, dislocation density, adhesion, and micro strain, and electrical …
Prediction Model For Compressive Strength Of Rock-Steel Fiber Reinforced Concrete Composite Layer, Meng Chen, Xiu-Wen Cui, Xin Yan, Hao Wang, Er-Lei Wang
Prediction Model For Compressive Strength Of Rock-Steel Fiber Reinforced Concrete Composite Layer, Meng Chen, Xiu-Wen Cui, Xin Yan, Hao Wang, Er-Lei Wang
Rock and Soil Mechanics
To study the uniaxial compressive strength calculation method of rock-steel fiber reinforced concrete (R-SFRC) composite layer, uniaxial compression test was carried out on rock, steel fiber reinforced concrete and R-SFRC composite layer specimens. The influence of concrete strength grades (C30, C40 and C50) and fiber contents (0, 40, 60 and 80 kg/m3) on the uniaxial compressive strength of steel fiber reinforced concrete and composite layers was analyzed. RFPA2D was utilized to simulate the damage process and stress-strain curve of the composite layer under uniaxial compression. The compressive strength prediction model of R-SFRC composite layer was established based on Mohr-Coulomb yield …
Numerical Simulation Of Aerodynamic Characteristics For Double-All-Wing Unmanned Aerial Vehicle Based On Computational Fluid Dynamics Theory, Kuizhi Yue, Zhang Yuan, Liangliang Cheng, Dazhao Yu
Numerical Simulation Of Aerodynamic Characteristics For Double-All-Wing Unmanned Aerial Vehicle Based On Computational Fluid Dynamics Theory, Kuizhi Yue, Zhang Yuan, Liangliang Cheng, Dazhao Yu
Journal of System Simulation
Abstract: Follow the rapid progress of the nation's blue ocean strategic projection capability of sea power, an Unmanned Aerial Vehicle (UAV) with double-all-wing configuration is studied to match the trend. The UAV is conceptually designed by CATIA software, the aerodynamic characteristic of the model is numerically simulated by computational fluid dynamics (Computational Fluid Dynamics, CFD) theory, and the performance of the UAV to take off from the aircraft carrier is also analyzed. The lift coefficient, drag coefficient and lift-drag ratio of the double-all-wing UAV model with a angle of attack of 0 can reach 0.596 2, 0.037 6 and 15.824 …
Research On The Evolution Law Of Roadway Surrounding Rock Fissure Based On Fractal Dimension, Ding Wanqi, Ma Zhenqian, Zu Ziyin, Xie Hongfei, Yang Wei, Chen Chuan
Research On The Evolution Law Of Roadway Surrounding Rock Fissure Based On Fractal Dimension, Ding Wanqi, Ma Zhenqian, Zu Ziyin, Xie Hongfei, Yang Wei, Chen Chuan
Coal Geology & Exploration
To explore the evolution law of surrounding rock fissures under the influence of horizontal stress and dynamic disturbance in argillaceous roadways, the deformation and failure characteristics of argillaceous roadways, the evolution law of surrounding rock fissures and the fractal evolution characteristics of surrounding rock fissures under dynamic disturbance are studied by such methods as field investigation, numerical simulation and fractal theory analysis, with the 226 track gate of Shanjiaoshu Mine in Panzhou City as the engineering background. The results show that before dynamic disturbance, the expansion range of fracture zone and plastic zone of roadways gradually increases with the increase …
Quantitative Study Of 3d Numerical Simulation On Optimizing Borehole Layout Spacing Of Gas Drainage, Chen Yuexia, Chu Tingxiang, Chen Peng, Tang Yang
Quantitative Study Of 3d Numerical Simulation On Optimizing Borehole Layout Spacing Of Gas Drainage, Chen Yuexia, Chu Tingxiang, Chen Peng, Tang Yang
Coal Geology & Exploration
In order to optimize the spacing of boreholes and realize efficient drainage, based on the fluid solid coupling model, a three-dimensional geometric model was established to make it closer to the field reality, the gas drainage processes of a coal mine with different borehole spacing were simulated using COMSOL software. The results show that: the effective drainage area was visualized by the three-dimensional diagram of the isobaric surface with gas pressure of 0.74 MPa, and the influence of borehole spacing on the extraction efficiency was discussed. The results show that: the effective extraction radius is about 1.5 m during gas …
Mining Subsidence Analysis Of Gently Inclined Coal Seams Based On Flac3d And Dem Data, Gan Zhihui, Shang Hui, Du Rongjun, Zhan Huizhu
Mining Subsidence Analysis Of Gently Inclined Coal Seams Based On Flac3d And Dem Data, Gan Zhihui, Shang Hui, Du Rongjun, Zhan Huizhu
Coal Geology & Exploration
Shizuishan Mining Area in Ningxia Province is located in the western Yellow River. The subsidence of the mined-out area causes frequent surface ecological and environmental problems. The analysis of coal mining subsidence will play a positive role in environmental remediation the Yellow River Basin. Taking Shizuishan Coal Mine as an object to study the evolution characteristics of surrounding rock stress and displacement field of gently inclined coal seam, a three-dimensional numerical model of the gently inclined coal seam based on the numerical simulation software FLAC3D was established. The variation of stress, plastic zone, and displacement in the surrounding rocks …
Numerical Simulation Of Open-Pit Mine Slope Based On Unmanned Aerial Vehicle Photogrammetry, Ai-Bing Jin, Shuai-Jun Chen, An-Yu Zhao, Hao Sun, Yu-Shuai Zhang
Numerical Simulation Of Open-Pit Mine Slope Based On Unmanned Aerial Vehicle Photogrammetry, Ai-Bing Jin, Shuai-Jun Chen, An-Yu Zhao, Hao Sun, Yu-Shuai Zhang
Rock and Soil Mechanics
Numerical simulation is a normal method for slope stability analysis in open-pit mines. Slope model construction is the basis of numerical simulation, and the accuracy of topographic measurement data has an important influence on the accuracy of slope stability analysis. In recent years, low-altitude and low-speed small unmanned aerial vehicles (UAVs) have been widely used in geological surveys, which provide a feasible method for rapid terrain measurement under complex conditions. Considering the situation of the rapid change of slope shape of the open-pit mine, the complex terrain, and the difficulty of manual measurement, a single-lens small unmanned aerial vehicle (UAV) …
Research On Random Propagation Method Of Hydraulic Fracture Based On Zero-Thickness Cohesive Element, Jun Li, Wen-Bao Zhai, Zhao-Wei Chen, Gong-Hui Liu, Ying-Cao Zhou
Research On Random Propagation Method Of Hydraulic Fracture Based On Zero-Thickness Cohesive Element, Jun Li, Wen-Bao Zhai, Zhao-Wei Chen, Gong-Hui Liu, Ying-Cao Zhou
Rock and Soil Mechanics
In order to effectively simulate the process of random propagation of hydraulic fractures in fractured shale reservoirs, a new method of random propagation of hydraulic fractures based on the finite element mesh embedded with zero-thickness cohesive elements is proposed. This new method is based on the topological data structure of element nodes and the splitting mode of mesh nodes. The accuracy and effectiveness of the random propagation method are verified by comparing with the analytical solution of KGD model and two kinds of laboratory experiments. Meanwhile, the influences of horizontal in-situ stress difference and reservoir heterogeneity on the process of …
Improving The 2d Numerical Simulations On Local Scour Hole Around Spur Dikes, Chung Ta Liao, Keh Chia Yeh, Yin Chi Lan, Ren Kai Jhong, Yafei Jia
Improving The 2d Numerical Simulations On Local Scour Hole Around Spur Dikes, Chung Ta Liao, Keh Chia Yeh, Yin Chi Lan, Ren Kai Jhong, Yafei Jia
Faculty and Student Publications
Local scour is a common threat to structures such as bridge piers, abutments, and dikes that are constructed on natural rivers. To reduce the risk of foundation failure, the understanding of local scour phenomenon around hydraulic structures is important. The well-predicted scour depth can be used as a reference for structural foundation design and river management. Numerical simulation is relatively efficient at studying these issues. Currently, two-dimensional (2D) mobile-bed models are widely used for river engineering. However, a common 2D model is inadequate for solving the three-dimensional (3D) flow field and local scour phenomenon because of the depth-averaged hypothesis. This …
Mechanism Research Of A New Constant Resistance Yielding Device For Tunnels, Chuan-Qing Zhang, Hao-An L, Xiao-Yan Liu, Hui Zhou, Yang Gao, Dong-Ming Yan
Mechanism Research Of A New Constant Resistance Yielding Device For Tunnels, Chuan-Qing Zhang, Hao-An L, Xiao-Yan Liu, Hui Zhou, Yang Gao, Dong-Ming Yan
Rock and Soil Mechanics
The constant resistance yielding support is the ideal form of support for squeezing tunnel. Current technology is difficult to satisfy the safety requirements of high bearing capacity, large deformation and load stability at the same time. In response to this problem, the constant resistance yielding device based on the principle of tension-compression conversion (CRYD-TCC) was developed inspired by the metal drawing process in combination with the working characteristics of steel arch support. In this paper, the working principle of the CRYD-TCC was discussed, and its mechanical response law and characteristics were analyzed. Through the indoor test and numerical simulation, the …
Numerical Simulation Of The Influence Of No-Flow Recharge Aquifer On Cbm Drainage, Liu Bing, Zhang Songhang, Tang Shuheng, Wang Pengfei, Zhai Jiayu, Ji Chaoqi
Numerical Simulation Of The Influence Of No-Flow Recharge Aquifer On Cbm Drainage, Liu Bing, Zhang Songhang, Tang Shuheng, Wang Pengfei, Zhai Jiayu, Ji Chaoqi
Coal Geology & Exploration
Coalbed methane wells in southern Qinshui Basin have the characteristics of high water yield and low gas yield, while some wells present high water yield and high gas yield characteristics. Generally speaking, the high water yield of coalbed methane wells is mostly related to the aquifer with recharge. In this case, based on the coal reservoir geological condition of Shizhuangnan Block and the actual situation of coalbed methane vertical well production, the influence of non-flow recharge aquifer on reservoir pressure variation and CBM outflow rule was simulated by using a three-dimensional coal reservoir simulation software (SIMEDWin) with gas and water …
Numerical Simulation And Test Of Gas Drainage With Water Jet Layered Pressure Relief And Permeability Enhancement In Soft Coal Seam, Liu Xiao, Li Yong, Xuan Dequan, Hu Shixiong, Jing Tianxiang, Xu Sen
Numerical Simulation And Test Of Gas Drainage With Water Jet Layered Pressure Relief And Permeability Enhancement In Soft Coal Seam, Liu Xiao, Li Yong, Xuan Dequan, Hu Shixiong, Jing Tianxiang, Xu Sen
Coal Geology & Exploration
Hydraulic punching is the main technical measure to enhance permeability and drainage of coal seam gas. The pressure relief effect is mainly evaluated by the coal output. However, there are some problems such as large coal output, uneven pressure relief and easy stress concentration. Therefore, this paper puts forward the soft coal interlayer water jet layered pressure relief and permeability increasing gas drainage technology. Considering the influence of gas pressure compression and coal matrix adsorption gas expansion on the coal mass deformation, a multiphysics theoretical model under the coupling condition of stress field, fracture field and seepage field was established. …
Rock Breaking Mechanism Of Composite Impact Of Full-Size Pdc Bit Based On Finite Element Analysis, Peng Xu, Hao Shijun
Rock Breaking Mechanism Of Composite Impact Of Full-Size Pdc Bit Based On Finite Element Analysis, Peng Xu, Hao Shijun
Coal Geology & Exploration
In order to solve the problems of low rock breaking efficiency in hard formation and the decrease of bit life caused by stick-slip vibration of drilling tools, the full-size bit composite impact rock breaking mechanism was studied by finite element method(ANSYS). The effects of impact frequency, WOB(weight on bit) and rotational speed on the efficiency of rock breaking were analyzed. It was found that both tensile and compressive stresses existed in rock during bit rock breaking, and rock failure was manifested in comprehensive failure of “tensile & compressive shear”. It is concluded that under the condition of torsional impact frequency …
Numerical Simulation Of Safe Distance Through Roadway Drilling Under Dynamic Load Of Large Diameter Rescue Well, Li Bizhi, Hao Shijun, Liu Mingjun, Zhang Qiang, Bai Gang, Mo Haitao
Numerical Simulation Of Safe Distance Through Roadway Drilling Under Dynamic Load Of Large Diameter Rescue Well, Li Bizhi, Hao Shijun, Liu Mingjun, Zhang Qiang, Bai Gang, Mo Haitao
Coal Geology & Exploration
Aiming at the sudden inburst of formation water and drilling fluid into a roadway along the borehole during through roadway drilling operation, which results in the secondary injury of the trapped personnel, ABAQUS geotechnical numerical simulation method was adopted, the model was established with the surface rescue well of the roadway of No.3 coal seam in Pingshang Coal Mine as an example, the plastic deformation characteristics of the surrounding rock of the roadway roof and the optimization of safe through roadway distance under drilling dynamic disturbance were studied. The results show that the dynamic disturbance caused displacement deformation and plastic …
Development Of Deep Geothermal Energy And Its Influence On Geothermal Water Flow Field: Taking The Development Of Deep Geothermal Energy In Lankao County For An Example, Song Qianjin, Wang Gang, Xu Yichuan, Cheng Lei
Development Of Deep Geothermal Energy And Its Influence On Geothermal Water Flow Field: Taking The Development Of Deep Geothermal Energy In Lankao County For An Example, Song Qianjin, Wang Gang, Xu Yichuan, Cheng Lei
Coal Geology & Exploration
In order to study the influence of deep geothermal energy development on the flow field of thermal reservoir, deep geothermal energy development in Lankao County is selected as the research object. The geological structure and regional structure of the study area since Cenozoic are analyzed, and the of geothermal exploitation and existing problems in the area are investigated. According to the types of geothermal energy, the characteristics of the Quaternary(Q), Neogene Minghuazhen Formation(N2) and Neogene Guantao Formation(N1) are analyzed. The conditions of fault distribution, thermal reservoir development and water-resisting boundary in the area are found out …
Study On Tunnel Water Inrush Mechanism And Simulation Of Seepage Failure Process, Zong-Qing Zhou, Li-Ping Li, Shao-Shuai Shi, Cong Liu, Cheng-Lu Gao, Wen-Feng Tu, Mei-Xia Wang
Study On Tunnel Water Inrush Mechanism And Simulation Of Seepage Failure Process, Zong-Qing Zhou, Li-Ping Li, Shao-Shuai Shi, Cong Liu, Cheng-Lu Gao, Wen-Feng Tu, Mei-Xia Wang
Rock and Soil Mechanics
In view of the two typical modes of water inrush disasters, progressive fracturing of rock mass and seepage failure of filling structure, the mechanism of progressive fracturing of rock mass under the combined effects of dynamic disturbance, excavation unloading and high water pressure is described. The seepage failure mechanism of the variable strength-variable permeability-variable viscosity of the filling structure under osmotic pressure is also expounded. For the variable viscosity mechanism of water inrush caused by seepage failure of filling structure, a qualitative simulation study on the effect of fluid viscosity on seepage failure mechanism is carried out using the DEM-CFD …
Study On Navigation Simulation Method Of Crude Oil Fleet In Bridge Area, Chunhui Zhou, Hongxun Huang, Wanxia Yi, Lijia Chen, Yuanqiao Wen, Linxu Tan
Study On Navigation Simulation Method Of Crude Oil Fleet In Bridge Area, Chunhui Zhou, Hongxun Huang, Wanxia Yi, Lijia Chen, Yuanqiao Wen, Linxu Tan
Journal of System Simulation
Abstract: In view of the safety of over-scale fleet sailing through bridge, the water area of Wuhan Yangtze River Bridge is taken as the research area. Numerical simulation of flow field is conducted based on MIKE software to analyze the changes of water flow in different water periods and their effects on ship navigation. On this basis, according to the simulation results of the flow field, several test conditions are set up by using the Large Ship Maneuvering Simulator to carry out the simulation test of over-scale fleet sailing through the bridge. The results show that under the preset wind …
Numerical Simulation Of Pore Structure Stress Characteristics Of Coal And Rock Mass, Wang Gang, Jiang Chenghao, Chen Xuechang
Numerical Simulation Of Pore Structure Stress Characteristics Of Coal And Rock Mass, Wang Gang, Jiang Chenghao, Chen Xuechang
Coal Geology & Exploration
In order to explore the stress distribution around the pores of coal and rock mass under different loading modes, the skeleton model of coal and rock mass with different pore shapes was constructed through CT three-dimensional reconstruction technology, and uniaxial and triaxial compression experiment simulations were conducted using ABAQUS software. The results showed that under uniaxial compression, the upper and lower regions of spherical pores showed tensile stress concentration, while the left and right regions showed compressive stress concentration. The stress concentration types in the long and short axis of elliptic pores were distinct with different dip angles. Under uniaxial …
Numerical Analysis On Csw Fracturing Behavior Of Coal Seam Under Constraint Of Geological And Engineering Conditions, Qin Yong, Li Hengle, Zhang Yongmin, Zhao Youzhi, Zhao Jincheng, Qiu Aici
Numerical Analysis On Csw Fracturing Behavior Of Coal Seam Under Constraint Of Geological And Engineering Conditions, Qin Yong, Li Hengle, Zhang Yongmin, Zhao Youzhi, Zhao Jincheng, Qiu Aici
Coal Geology & Exploration
As a revolutionary technology for rock stratum reformation, the controllable shock wave(CSW) fracturing technology has achieved remarkable effect in coal seam reconstruction, and application exploration in the field of coal safety mining has been carried out. However, the previous understanding of the basic CWS fracturing rules under the constraints of geological engineering factors is insufficient due to the limitation of experimental and field monitoring conditions, which restricts the exploration of the fracturing mechanism and the optimization of the field operation parameters. In view of this, based on the description of CSW coal seam reformation and its engineering scientific problems, the …
Investigation And Simutation On The Model And Prevention Technology Of Water Inrush From Roof Bed Separation, Zhang Wenquan, Wang Zaiyong, Wu Xintao, Shao Jianli, Lei Yu, Wu Xunan
Investigation And Simutation On The Model And Prevention Technology Of Water Inrush From Roof Bed Separation, Zhang Wenquan, Wang Zaiyong, Wu Xintao, Shao Jianli, Lei Yu, Wu Xunan
Coal Geology & Exploration
In order to prevent water inrush from roof separation, a partial backfill scheme is proposed for simulation study. First of all, based on the existing data, many kinds of separation water inrush accidents occurred in China were summarized and analyzed, and the disaster model of separation water accumulation was studied deeply. Then, taking the separation water accident of 1307 working face in the first mining area of a mine in Shaanxi Province as an example, the hydrogeological conditions and the relationship between upper aquifer and separation water inrush were analyzed, and the development characteristics of roof separation space of working …
Single-Particle Crushing Test And Numerical Simulation Of Coarse Grained Soil Based On Size Effect, Min-Qiang Meng, Lei Wang, Xiang Jiang, Cheng-Gui Wang, Han-Long Liu, Yang Xiao
Single-Particle Crushing Test And Numerical Simulation Of Coarse Grained Soil Based On Size Effect, Min-Qiang Meng, Lei Wang, Xiang Jiang, Cheng-Gui Wang, Han-Long Liu, Yang Xiao
Rock and Soil Mechanics
The coarse-grained soil is prone to particle breakage under external loads and other factors. A series of single-particle fragmentation tests is conducted for mudstone and sandstone particles. Based on the size effect and fractal model of particle fragmentation, the relationships between the fractal dimension and single-particle crushing strength, fragmentation energy, and Weibull modulus are investigated. A single particle crushing process is analyzed using PFC3D and the modelling results are compared with that from the experimental data to verify the reliability of numerical code. The crushing strength and crushing energy of large particle size are then analyzed by numerical models. The …
Time Domain Boundary Element Method Prediction Of Noise Shielding By A Naca 0012 Airfoil, Douglas M. Nark, Fang Q. Hu
Time Domain Boundary Element Method Prediction Of Noise Shielding By A Naca 0012 Airfoil, Douglas M. Nark, Fang Q. Hu
Mathematics & Statistics Faculty Publications
As aircraft noise constraints become more stringent and the number/mixture of aircraft configurations grows, it becomes more important to understand the interaction of individual aircraft noise sources with nearby aircraft structures. Understanding these interactions and exploring possible approaches to mitigate or exploit their acoustic impact is essential for overcoming key noise barriers. This paper describes the further validation of a time domain boundary element approach for the prediction of the interactions between incident noise sources and nearby aircraft structures. Predictions were completed for multiple source locations and comparisons of these results with measured data are presented. Overall, very good agreement …
Numerical Assessment Of The Overall Heat Transfer And Pressure Drop Performances Of An Aqueous Ammonia Base-Nanofluids In Rectangular Microchannel Heat Sinks, Ahmed Mohammed Adham, Hussein A. Mohammed
Numerical Assessment Of The Overall Heat Transfer And Pressure Drop Performances Of An Aqueous Ammonia Base-Nanofluids In Rectangular Microchannel Heat Sinks, Ahmed Mohammed Adham, Hussein A. Mohammed
Research outputs 2014 to 2021
In this paper, the thermal and hydrodynamic performances of an aqueous ammonia base-nanofluid (Al2O3-NH3(aqu)) cooled in a rectangular microchannel heat sink was numerically investigated. The range of Reynolds number used in the investigation were between 140-1400. In order to assess the performance of the system during the employment of the proposed nanofluid, H2O and Al2O3-H2O were also tested and their performances were compared to Al2O3-NH3(aqu) performance in terms of thermal resistance and pressure drop. Results from the simulation showed that the proposed nanofluid outperformed pure water and slightly higher than Al2O3-H2O in terms of thermal resistance (for Re = 1400, …