检索结果-南通市图书馆

SI Engine Fueled with Gasoline, CNG and CNG-HHO Blend: Comparative Evaluation of Performance, Emission and Lubrication Oil Deterioration

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2021年第4期30卷 1199-1211页

作者： USMAN Muhammad hayat Nasir BHUTTA Muhammad Mahmood Aslam Department of Mechanical Engineering University of Engineering and TechnologyLahore 54890Pakistan

Hydroxy gas (HHO) is one of the potential alternative fuels for spark ignition (SI) engine,notably due to simultaneous increase in engine performance and reduction in exhaust ***,impact of HHO gas on lubrication oil for longer periods of engine operation has not yet been *** study focuses on investigation of the effect of gasoline,CNG and CNG-HHO blend on lubrication oil deterioration along with engine performance and emissions in SI *** unit produces HHO gas at 4.72 L/min by using 6 g/L of KOH in the aqueous *** was supplied to the test engine at a pressure of 0.11 MPa using an electronically controlled solenoid *** tests were carried out at different speeds at 80%open throttle condition and various performance parameters such as brake power (BP),brake specific fuel consumption(BSFC),brake thermal efficiency (BTE),exhaust gas temperature and exhaust emissions (HC,CO_(2),CO and NO_(x))were *** addition,various lubrication oil samples were extracted over 120 h of engine running while topping for drain out volume and samples were analyzed as per ASTM ***-HHO blend exhibited better performance i.e.,15.4%increase in average BP in comparison to CNG,however,15.1%decrease was observed when compared to ***-HHO outperformed gasoline and CNG in the case of HC,CO_(2),CO and brake specific fuel consumption (31.1%decrease in comparison to gasoline).On the other hand,CNG-HHO produced higher average NO_(x) (12.9%) when compared to CNG ***,lubrication oil condition(kinematic viscosity,water contents,flash point and total base number (TBN)),wear debris (Iron (Fe),Aluminum(Al),Copper (Cu),Chromium (Cr)) and additives depletion (Zinc (Zn),Calcium (Ca)) presented a significant degradation in the case of CNG-HHO blend as compared to gasoline and *** oil analyses illustrated 19.6%,12.8%and 14.2%decrease in average viscosity,flash point and TBN for CNG-HHO blend ***,

关键词： spark ignition engine compressed natural gas hydrogen lubrication oil deterioration emission

Solitary Wave Solutions of Some Nonlinear Physical Models Using Riccati Equation Approach

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2020年第2期36卷 401-418页

作者： Zaid ODIBAT Ahmed ALSAEDI Tasawar hayat School of Basic Sciences and umanities German Jordanian UniversityAmman 11180Jordan Nonlinear Analysis and Applied Mathematics(NAAM)Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics Quaid-I-Azam UniversityIslamabad 44000Pakistan

Riccati equation approach is used to look for exact travelling wave solutions of some nonlinear physical *** wave solutions are established for the modified KdV equation,the Boussinesq equation and the Zakharov-Kuznetsov *** generalized solitary wave solutions with some free parameters are *** obtained solutions,which includes some previously known solitary wave solutions and some new ones,are expressed by a composition of Riccati differential equation solutions followed by a *** employed approach,which is straightforward and concise,is expected to be further employed in obtaining new solitary wave solutions for nonlinear physical problems.

关键词： solitary wave solution Riccati equation the modified KdV equation the Boussinesq equation the Zakharov-Kuznetsov equation

Flow of Burgers' fluid over an inclined stretching sheet with heat and mass transfer

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2015年第8期22卷 3180-3188页

作者： T.hayat Sadia Asad A.Alsaedi Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Department of Mathematics Faculty of Science King Abdulaziz University

Effects of heat and mass transfer in the flow of Burgers fluid over an inclined sheet are discussed. Problems formulation and relevant analysis are given in the presence of thermal radiation and non-uniform heat source/sink. Thermal conductivity is taken temperature dependent. The nonlinear partial differential equations are simplified using boundary layer approximations. The resultant nonlinear ordinary differential equations are solved for the series solutions. The convergence of series solutions is obtained by plotting theη-curves for the velocity, temperature and concentration fields. Results of this work describe the role of different physical parameters involved in the problem. The Deborah numbers corresponding to relaxation time(β1 and β2) and angle of inclination(α) decrease the fluid velocity and concentration field. Concentration field decays as Deborah numbers corresponding to retardation time(β3) and mixed convection parameter(G) increase. Large values of heat generation/absorption parameters A/B, and the temperature distribution across the boundary layer increase. Numerical values of local Nusselt number,-θ′(0), and local Sherwood number,-f′(0), are computed and analyzed. It is found that θ′(0) increases with an increase in β3.

关键词： Burgers' fluid thermal radiation inclined stretching sheet non-uniform heat source variable thermal conductivity

Variable viscosity in peristalsis of Sisko fluid

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2018年第4期39卷 501-512页

作者： A.TANVEER T.hayat A.ALSAEDI Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Department of Mathematics Faculty of Science King Abdulaziz University

This paper aims to examine variable viscosity effects on peristalsis of Sisko fluids in a curved channel with compliant characteristics. Viscous dissipation in a heat transfer is studied. The resulting problems are solved using perturbation and numerical schemes to show qualitatively similar responses for velocity and temperature. A streamline phenomenon is also considered.

关键词： peristalsis Sisko fluid curved channel numerical and perturbation solution wall property viscous dissipation

MHD boundary layer flow of Casson fluid passing through an exponentially stretching permeable surface with thermal radiation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2014年第10期23卷 306-314页

作者： Swati Mukhopadhyay Iswar Chandra Moindal Tasawar hayat Department of Mathematics The University of Burdwan Department of Mathematics Quaid-i-Azam University 45320 Islamabad Pakistan Department of Mathematics Faculty of Science King Abdulziz University Jeddah 21589 Saudi Arabia

This article numerically examines the boundary layer flow due to an exponentially stretching surface in the presence of an applied magnetic field. Casson fluid model is used to characterize the non-Newtonian fluid behavior. The flow is subjected to suction/blowing at the surface. Analysis is carded out in presence of thermal radiation and prescribed surface heat flux. In this study, an exponential order stretching velocity and prescribed exponential order surface heat flux are accorded with each other. The governing partial differential equations are first converted into nonlinear ordinary differential equations by using appropriate transformations and then solved numerically. The effect of increasing values of the Casson parameter is to suppress the velocity field. However the temperature is enhanced when Casson parameter increases. It is found that the skin-friction coefficient increases with increasing values of suction parameter. Temperature also increases for large values of power index n in both suction and blowing cases at the boundary. It is observed that the thermal radiation enhances the effective thermal diffusivity and hence the temperature rises.

关键词： exponential stretching suction/blowing prescribed heat flux thermal radiation

Laser-assisted ablation and plasma formation of titanium explored by LIBS,QCM, optical microscopy and SEM analyses along with mechanical modifications under different pressures of Ar and Ne

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2023年第3期25卷 181-192页

作者： Maryam RIAZ Shazia BASHIR Asma hayat Zarish NAZ Centre for Advanced Studies in Physics GC University Lahore

This study deals with the investigation of Nd:YAG laser-assisted ablation and plasma formation of Ti at irradiance of 0.85 GW cm-2 under Ar and Ne environment at various pressures ranging from 10-120 ***-induced breakdown spectroscopy is used to evaluate plasma parameters,whereas quartz crystal microbalance is used for ablation yield *** crater depth is evaluated by optical *** surface features are explored by scanning electron microscope(SEM) analysis and the micro-hardness is measured by a Vickers hardness *** is observed that the plasma parameters are higher in Ar than in Ne,and are strongly correlated with the ablation yield,ablation depth,surface features and hardness of laser-ablated *** parameters increase with increasing the pressure of environmental gases,attain their maxima at 40 Torr for Ar and at 60 Torr for ***,they show a decreasing trend up till a maximum pressure of 120 *** maximum value of the electron temperature(Te) is5480 K,number density(ne) is 1.46 × 1018 cm-3,ablation depth is 184 μm,ablation yield is3.9 × 1015 atoms/pulse and hardness is 300 HV in the case of Ar *** analysis reveals the growth of surface features,such as cones,ridges and pores,whose appearance is more distinct in Ar than Ne and is attributed to temperature,pressure and density gradients along with recoil pressure of the Ti plasma.

关键词： ablation plasma electron temperature electron density laser-induced breakdown spectroscopy surface structures

Flow of couple stress fluid with variable thermal conductivity

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2016年第3期37卷 315-324页

作者： S.ASAD A.ALSAEDI T.hayat Department of Mathematics COMSATS Institute of Information Technology Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of Science King Abdulaziz University Department of Mathematics Quaid-i-Azam University

The steady flow and heat transfer of a couple stress fluid due to an inclined stretching cylinder are analyzed. The thermal conductivity is assumed to be temperature dependent. The governing equations for the flow and heat transfer are transformed into ordinary differential equations. Series solutions of the resulting problem are computed. The effects of various interested parameters, e.g., the couple stress parameter, the angle of inclination, the mixed convection parameter, the Prandtl number, the Reynolds number, the radiation parameter, and the variable thermal conductivity parameter, are illustrated. The skin friction coefficient and the local Nusselt number are computed and analyzed. It is observed that the heat transfer rate at the surface increases while the velocity and the shear stress decrease when the couple stress parameter and the Reynolds number increase. The temperature increases when the Reynolds number increases.

关键词： couple stress fluid thermal radiation variable thermal conductivity

iRNA-PseTNC:identification of RNA 5-methylcytosine sites using hybrid vector space of pseudo nucleotide composition

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2020年第2期14卷 451-460页

作者： Shahid AKBAR Maqsood hayat Muhammad IQBAL Muhammad TAHIR Department of Computer Science Abdul Wali Khan University MardanKP 23200Pakistan

RNA 5-methylcytosine(m^5C)sites perform a major role in numerous biological processes and commonly reported in both DNA and RNA *** enzymatic mechanism and biological functions of m^5C sites in DNA remain the focusing area of researchers for last few ***,the investigators also targeted m^5C sites in RNA due to its cellular functions,positioning and formation ***,several rudimentary roles of the m^5C in RNA have been explored,but a lot of improvements are still under ***,the identification of RNA methylcytosine sites was carried out via experimental methods,which were very hard,erroneous and time consuming owing to partial availability of recognized *** at the significance of m^5C role in RNA,scientists have diverted their attention from structure to sequence-based *** this regards,an intelligent computational model is proposed in order to identify m^5C sites in RNA with high *** RNA sequences formulation methods namely:pseudo dinucleotide composition,pseudo trinucleotide composition and pseudo tetra nucleotide composition are applied to extract variant and high profound numerical *** a sequel,the vector spaces are fused to build a hybrid space in order to compensate the weakness of each *** learning hypotheses are examined to select the best operational engine,which can truly identify the pattern of the target *** strength and generalization of the proposed model are measured using two different cross validation *** reported outcomes reveal that the proposed model achieved 3%better accuracy than that of the highest present approach in the literature so far.

关键词： methylcytosine sites PseTNC PseTetraNC hybrid features SVM cross validation test

Three-dimensional mixed convection squeezing flow

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2015年第1期36卷 47-60页

作者： T.hayat A.QAYYUM A.ALSAEDI Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of Science King Abdulaziz University

The unsteady mixed convection squeezing flow of an incompressible Newtonian fluid between two vertical parallel planes is discussed. The fluid is electrically conducting. The governing equations are transformed into ordinary differential equations （ODEs） by appropriate transformations. The transformed equations are solved successfully by a modern and powerful technique. The effects of the emerging parameters on the flow and heat transfer characteristics are studied and examined. The values of the skin friction coefficient and the local Nusselt number are tabulated and analyzed.

关键词： squeezing flow, mixed convection, vertical rotating channel unsteadystretching porous sheet