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Heat Transfer Enhancement of an Automobile Engine Radiator using ZnO Water Base Nanofluids

Journal of Thermal Science 2020年第4期29卷 1010-1024页

作者： muhammad QASIM muhammad SAJID KAMRAN muhammad AMMAR muhammad ali jamal muhammad YASAR JAVAID Department of Mechanical Engineering University of Engineering and TechnologyLahore 54890Pakistan Department of Chemical Engineering Technology Government College UniversityFaisalabad 38000Pakistan Department of Mechanical Engineering Technology Government College UniversityFaisalabad 38000Pakistan

In this research paper, the forced convective heat transfer enhancement of a Suzuki Mehran(VXR) 2016 radiator(heat exchanger) along with pressure drop and friction factor by utilizing Zinc oxide(Zn O) water based nanofluids has been experimentally studied. Three types of nanofluids with different volumetric concentrations of Zn O nanoparticles(0–0.3%) were employed in order to understand its effect on heat transfer enhancement. The experimental setup was completely designed as closely as possible to the car cooling system. The experimentation has been done under laminar flow conditions(186≤Re≤1127) at different fluid volume flow rates(2–12 L/min) and constant fluid inlet temperature(70°C) to the automobile radiator. A maximum enhancement in heat transfer rate, overall heat transfer coefficient and Nusselt number was obtained up to 41%, 50% and 31% by using nanofluid with 0.2% volumetric concentration of nanoparticles respectively. On the other hand, the mean enhancement in pressure drop and friction factor was obtained up to 47% and 46% by using nanofluid with the same volumetric concentration of nanoparticles i.e. 0.2% respectively. The experimental results also revealed that the heat transfer rate, overall heat transfer coefficient and Nusselt number of nanofluids increases by increasing the volume flow rates and volumetric concentration of nanoparticles. However, these thermal performance parameters of nanofluids started to decline when the volumetric concentration of nanoparticles was increased from 0.2% to 0.3%. Furthermore, pressure drop and friction factor of nanofluids increase by increasing the volumetric concentration of nanoparticles, while pressure drop increases and friction factor decreases by increasing the volume flow rate of nanofluids respectively. At the end, the thermal efficiency of automobile radiator with high cooling rates was obtained by using nanofluid with 0.2% volumetric concentration of nanoparticles.

关键词： ZnO nanoparticles heat transfer enhancement thermal efficiency automobile radiator

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Numerical and experimental investigations of liquid mixing in two-stage micro-impinging stream reactors

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Chinese Journal of Chemical Engineering 2017年第4期25卷 391-400页

作者： Tianyu Guo Bin Ruan Zhiwei Liu muhammad ali jamal Lixiong Wen Jianfeng Chen State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China

A two-stage micro-impinging stream reactor(TS-MISR) that combined a first pre-mixing stage with a second micro-impinging stream reacting stage for continuous multi-component reacting systems has been built from commercial T-junctions and steel micro-capillaries. Both of operating parameters and reactor configurations,such as jet Reynolds number(Rej), volumetric flow ratio(R), the first-stage junction angle(φ), the connecting capillary length(Lc) and connecting capillary diameter(dc), had significant effects on the micromixing efficiency of the reactor. Such effects were investigated for both of the two stage structures, respectively, by experimental and CFD methods and were optimized for the best micromixing performance. Intensified micromixing among at least three reacting components can be achieved in a continuous mode by using TS-MISR; therefore, it is expected that the TS-MISR will produce products of higher quality with more uniform and stable element distribution.

关键词： mixing junction volumetric connecting reacting capillary length turbulence viscosity outlet

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多通道撞击流微反应器微观混合性能的CFD模拟研究

多通道撞击流微反应器微观混合性能的CFD模拟研究

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作者： muhammad ali jamal 北京化工大学

学位级别：硕士

反应器是化学工业中最重要的工具。几十年来,反应器的强化过程已经吸引了广泛的关注。反应器强化的关键是强化其在分子尺度上的混合性能,因为它决定了所有化学反应的各种参数,如选择性、产量、副产物的生成和放热等。人们做了大量的工... 详细信息

反应器是化学工业中最重要的工具。几十年来,反应器的强化过程已经吸引了广泛的关注。反应器强化的关键是强化其在分子尺度上的混合性能,因为它决定了所有化学反应的各种参数,如选择性、产量、副产物的生成和放热等。人们做了大量的工作以达到同时减小反应器尺寸和增强其混合性能的目的,其中所涉及到的反应器有微通道反应器、毛细管反应器、撞击流反应器和旋转反应器等。这些反应器的设计原则是改善其传质效率。通常增强反应器传质效率的途径是通过增大流体间的接触面积或者增大流体的初始速度来形成撞击。与传统的化学反应器相比,这些新型的反应器在改善混合性能方面表现卓越并被应用到一系列的化工过程,如聚合物、催化剂和纳米粉体的制备、萃取过程和吸收过程等。然而,这些反应器依然存在着一些问题,如处理量不大、通道堵塞、难以制造和组装、价格昂贵和难以放大等,这些问题严重限制了其在大型化学工业中的应用。本文提出了一种多通道微撞击流反应器。它具有四个通道和一个大的反应区。反应器的出口很大以确保反应后的流体能平滑地流出。反应器的进口可以根据需要灵活地调整为一、二或四个。通过增强各组分间的相互作用使得该反应器的混合性能和传质效率得到显著提升。流体由四个入口以较高的流速分别进入反应器并在混合区域强烈撞击,这就使得流体破碎程度加强从而增强了组分间在分子尺度上的相互作用。多通道微撞击流反应器的微观混合性能相当优良。本论文的主要研究内容如下:(1)提出了一种多通道微撞击流反应器,借助“碘化物-碘酸盐”平行竞争反应体系以离集指数为评价指标研究了反应器的微观混合性能,考察了雷诺数对微观混合的影响,结果表明离集指数随着雷诺数的增大而减小,当雷诺数大于3000时,离集指数的数量级达到10-5,表明反应器在此操作条件下具有较高的微观混合效率。(2)利用CFD技术研究了反应器的微观混合性能,其中采用了 k-ε湍流模型、欧拉多相模型和有限速率组分运输模型并考虑到了瞬态和重力因素的影响。CFD数值模拟结果与实验数据吻合良好。所得出的可视流场图能帮助我们更好地了解反应前和反应后的水-空气两相和流体间的相互作用。(3)通过增加反应前的入口数量考察了该反应器的放大规律,并且研究了进口数和流体流量对混合性能的影响。通过比较不同入口数的流场信息得出:增加该反应器的入口数量对其微观混合性能的改善并不明显。在雷诺数大于3000时,入口数为一、二或四个的反应器的离集指数几乎一致。这可能是因为高流速状态下两股流体已经形成了良好的撞击混合。与其他形式的微反应器相比,多通道微撞击流反应器有许多优势,如处理量大、无出口堵塞问题,较好的混合性能和传质效率等。这也为其应用于聚合反应和纳米材料的制备提供了便利。微反应器的工业化放大对于工程师而言一直是个难题,多通道微撞击流反应器的提出为研究者和工程师们提供了新思路。

关键词：多通道微撞击流反应器微观混合 CFD模拟欧拉模型

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Optimization of moderator assembly for neutron flux measurement:experimental and theoretical approaches

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Nuclear Science and Techniques 2017年第5期28卷 7-12页

作者： Abdul Waheed Nawab ali Muzahir A.Baloch Aziz A.Qureshi Eid A.Munem muhammad Usman Rajput Tauseef jamal Wazir muhammad Radiation Physics Laboratory Physics DepartmentCOMSATS Institute of Information Technology(CIIT)

A moderator of paraffin wax assembly has been demonstrated where its thickness can be optimized to thermalize fast neutrons. The assembly is used for measuring fast neutron flux of a neutron probe at different neutron energies, using BF03(U10and 200) and3He(U0.500)neutron detectors. The paraffin wax thickness was optimized at 6 cm for the neutron probe which contains an Am–Be neutron source. The experimental data are compared with Monte Carlo simulation results using MCNP5 version 1.4. Neutron flux comparison and neutron activation techniques are used for measuring neutron flux of the neutron probe to validate the optimum paraffin moderator thickness in the assembly. The neutron fluxes are measured at(1.17 ± 0.09) 9 105 and(1.19 ± 0.1) 9 105n/s, being in agreement with the simulated values. The moderator assembly can easily be utilized for essential requirements of neutron flux measurements.

关键词： Am–Be and 252Cf neutron sources BF3&3He detectors Paraffin wax Neutron flux Monte Carlo simulation

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Exploring multi-level risk factors and post-war burdens of trachomatous trichiasis among displaced population in Raya Kobo districts, implication for urgent action

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International Journal of Ophthalmology(English edition) 2023年第8期16卷 1299-1308页

作者： muhammad jamal Fassikaw Kebede Mersa Health Center Habru Woreda North WolloWoldiaAmhara 400Ethiopia School of Public Health College of Health ScienceWoldia UniversityWoldiaAmhara 400Ethiopia

AIM:To estimate post-war burdens of trachomatous trichiasis(TT)and multi-level risk factors among displaced population in Raya Kobo districts,implication for urgent ***:A community-based cross-sectional study was conducted among 603 participants from randomly selected 14 displaced slums in the Raya Kobo *** data was collected from February 16th to March 30th,*** participants were selected using the multistage sampling technique.A structured questionnaire and ophthalmic loupe with×2.5 magnificence were used to collect from ***-level binary logistic regression was used to determine associated factors with TT *** odds ratio(AOR)with 95%confidence interval(CI)were claimed for the strength of association at Paling up surgery,antibiotics,facial cleanliness,and environmental improvement(SAFE)strategies,strategy for high-risk ***≥45y,distance from the clean water source,poor wealth indexes,and eye infection are identified to be risk factors for TT ***,community-level preventative factors for TT infection are found as latrine availability and face washing practice.

关键词： trachoma risk factor displaced population

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Trihydrazinotrazine-grafting Fe_(3)O_(4)/SiO_(2) core-shell nanoparticles with expanded porous structure for organic reactions

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Frontiers of Chemical Science and Engineering 2021年第4期15卷 1008-1020页

作者： jamal Rahimi Seyedeh Shadi Mirmohammadi ali Maleki Catalysts and Organic Synthesis Research Laboratory Department of ChemistryIran University of Science and TechnologyTehran 16846-13114Iran

This study focuses on the synthesis and characterization of a novel magnetic nanocomposite 2,4,6-trihydrazino-1,3,5-triazine(THDT)-fimctionalized with silica-coated iron oxide magnetic nanoparticles(MNPs).This nanocomposite has porous morphology decorated with the spherical *** co-precipitation of iron salts,MNPs were *** prepared THDT was placed on the chlorine surface-modified *** present environment-friendly nanocatalyst intensely accelerated the synthesis of highly functionalized tetra-hydrobenzo[b]pyran derivatives as well as reduced the reaction times and increased yields of the products.

关键词： trihydrazino-triazine porous magnetic nanocatalyst green chemistry tetrahydrobenzo[b]pyrans

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Brain Tumor Detection and Classification Using PSO and Convolutional Neural Network

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Computers, Materials & Continua 2022年第12期73卷 4501-4518页

作者： muhammad ali jamal Hussain Shah muhammad Attique Khan Majed Alhaisoni Usman Tariq Tallha Akram Ye Jin Kim Byoungchol Chang Department of Computer Science COMSATS University IslamabadWah CampusPakistan Departmnt of Computer Science HITEC University TaxilaPakistan Computer Sciences Department College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia College of Computer Engineering and Sciences Prince Sattam bin Abdulaziz UniversityAl-KharjSaudi Arabia Department of EE COMSATS University IslamabadWah CampusPakistan Department of Computer Science Hanyang UniversitySeoul04763Korea Center for Computational Social Science Hanyang UniversitySeoul04763Korea

Tumor detection has been an active research topic in recent years due to the high mortality *** vision(CV)and image processing techniques have recently become popular for detecting tumors inMRI *** automated detection process is simpler and takes less time than manual *** addition,the difference in the expanding shape of brain tumor tissues complicates and complicates tumor detection for *** proposed a newframework for tumor detection aswell as tumor classification into relevant categories in this *** tumor segmentation,the proposed framework employs the Particle Swarm Optimization(PSO)algorithm,and for classification,the convolutional neural network(CNN)*** preprocessing techniques such as noise removal,image sharpening,and skull stripping are used at the start of the segmentation ***,PSO-based segmentation is *** the classification step,two pre-trained CNN models,alexnet and inception-V3,are used and trained using transfer *** a serial approach,features are extracted from both trained models and fused features for final *** classification,a variety of machine learning classifiers are *** dice values on datasets BRATS-2018 and BRATS-2017 are 98.11 percent and 98.25 percent,respectively,whereas average jaccard values are 96.30 percent and 96.57%(Segmentation Results).The results were extended on the same datasets for classification and achieved 99.0%accuracy,sensitivity of 0.99,specificity of 0.99,and precision of ***,the proposed method is compared to state-of-the-art existingmethods and outperforms them.

关键词： Magnetic resonance imaging(MRI) tumor segmentation deep learning features extraction classification

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Airship aerodynamic model estimation using unscented Kalman filter

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1318-1329页

作者： WASIM muhammad ali Ahsan Department of Electrical Engineering University of Engineering and TechnologyTaxila 47080Pakistan

An airship model is made-up of aerostatic,aerodynamic,dynamic,and propulsive forces and *** others,the computation of aerodynamic forces and torques is ***,wind tunnel experimentation and potential flow theory are used for their ***,the limitations of these methods pose difficulties in their accurate *** this work,an online estimation scheme based on unscented Kalman filter(UKF)is proposed for their *** proposed method introduces six auxiliary states for the complete aerodynamic *** uses an extended model and provides an estimate of a complete state vector along with auxiliary *** proposed method uses the minimum auxiliary state variables for the approximation of the complete aerodynamic model that makes it computationally less *** estimation performance is evaluated by developing a nonlinear simulation environment for University of Engineering and Technology,Taxila(UETT)*** performance is vali􀅫dated by performing the error analysis based on estimation error and 2-σ uncertainty *** the same problem,the extended Kalman filter(EKF)is also implemented and its results are compared with *** simulation results show that UKF successfully estimates the forces and torques due to the aerodynamic model with small estimation error and the comparative analysis with EKF shows that UKF improves the estimation re􀅫sults and also it is more suitable for the under-consideration problem.

关键词： airship unscented Kalman filter(UKF) extend Kalman filter(EKF) state estimation aerodynamic model estimation

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Compact Multibeam Array with Miniaturized Butler Matrix for 5G Applications

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Computers, Materials & Continua 2022年第7期72卷 925-937页

作者： Suleiman A.Babale muhammad K.Ishfaq ali Raza jamal Nasir Ahmad Fayyaz Umer Ijaz Department of Electrical Engineering Bayero UniversityKanoNigeria Department of Electrical Engineering Government College University FaisalabadPakistan Department of Electrical and Computer Engineering COMSATS University IslamabadAbbottabad CampusPakistan

This paper presents the design and implementation of a miniaturized beam steering network that produces broadside beams when it is fed with a compact antenna *** Matrix(BM)was used as the beam steering *** was completely built from a miniaturized 3 dB hybrid-couplers in planar microstrip *** was configured by feeding the BM with a Planar Inverted-E Antenna(PIEA)array separated at 0.3λas against the 0.5λ*** makes the BM produce a major radiation pattern at the *** from the miniaturization,no modification was made from the BM ***,employing effective mutual coupling reduction techniques helped to design the compact PIEA *** validity of this BM based multibeam PIEA array was demonstrated by comparing the simulation results of the reflection coefficients,transmissions coefficients and the radiation pattern with *** measurement results showed good agreement with simulations.

关键词： Beam steering compact butler matrix grating lobe and mutual coupling PIEA array

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Enhancing Secure Development in Globally Distributed Software Product Lines: A Machine Learning-Powered Framework for Cyber-Resilient Ecosystems

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Computers, Materials & Continua 2024年第6期79卷 5031-5049页

作者： Marya Iqbal Yaser Hafeez Nabil Almashfi Amjad Alsirhani Faeiz Alserhani Sadia ali Mamoona Humayun muhammad jamal University Institute of Information Technology PMAS-Arid Agriculture UniversityRawalpindiPakistan Department of Software Engineering College of Computer and Information SciencesJouf UniversityAl Jouf72388Saudi Arabia Department of Computer Science College of Computer and Information SciencesJouf UniversityAl Jouf72388Saudi Arabia Department of Computer Engineering&Networks College of Computer and Information SciencesJouf UniversityAl Jouf72388Saudi Arabia Department of Information Systems College of Computer and Information SciencesJouf UniversitySakakaAl Jouf72388Saudi Arabia Department of Mathematics Pir Mehr Ali Shah Arid Agriculture UniversityRawalpindiPakistan

Embracing software product lines(SPLs)is pivotal in the dynamic landscape of contemporary software ***,the flexibility and global distribution inherent in modern systems pose significant challenges to managing SPL variability,underscoring the critical importance of robust cybersecurity *** paper advocates for leveraging machine learning(ML)to address variability management issues and fortify the security of *** the context of the broader special issue theme on innovative cybersecurity approaches,our proposed ML-based framework offers an interdisciplinary perspective,blending insights from computing,social sciences,and ***,it employs ML for demand analysis,dynamic feature extraction,and enhanced feature selection in distributed settings,contributing to cyber-resilient *** experiments demonstrate the framework’s superiority,emphasizing its potential to boost productivity and security in *** digital threats evolve,this research catalyzes interdisciplinary collaborations,aligning with the special issue’s goal of breaking down academic barriers to strengthen digital ecosystems against sophisticated attacks while upholding ethics,privacy,and human values.

关键词： Machine Learning variability management cybersecurity digital ecosystems cyber-resilience

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