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Multidimensional modeling of the effect of fuel injection pressure on temperature distribution in cylinder of a turbocharged DI diesel engine

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Propulsion and Power Research 2013年第2期2卷 162-175页

作者： Sajjad Emami Samad Jafarmadar Young Researchers and Elie Club Khoy BranchIslamic Azad UniversityKhoyWest Azerbaijian 58159-15149Iran Mechanical Engineering Department Technical Education FacultyUmia UniversityUmiaWest Azerbaijan 57561-15311Iran

In this study,maintaining a constant fuel rate,injection pressure of 275 bar to1000 bar(275 × 10^(2) kPa to 1000× 10^(2) kPa),has been *** of injection pressure,the pressure inside the cylinder on the free energy,power,engine indicators,particularlyindicators of fuel consumption,pollutants and their effects on parameters affecting the outputof the engine combustion chamber have been studied in droplet ***,the effects offuel mixture equivalence,Cantor temperature,soot and NO_(x),due to the increase of injectionpressure,engine efficiency and emissions have been examined.

关键词： injection pressure Indicated power Temperature contour Equivalence contour Soot NO_(x) Combustion modeling

Analysis of the Emissions and Performance of a Diesel Engine Using Pumpkin Seed Oil Methyl Ester with Different injection pressures

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Fluid Dynamics & Materials Processing 2023年第4期19卷 1003-1014页

作者： Surendrababu Kuppusamy Prabhahar Muthuswamy Muthurajan Kumarasamy Sendilvelan Subramanian Research Scholar Department of Mechanical EngineeringVinayaka Missions Research FoundationChennai603104India Department of Mechanical Engineering Aarupadai Veedu Institute of TechnologyVinayaka Missions Research FoundationChennai603104India Department of Mechanical Engineering Vinayaka Mission’s Kirupananda Variyar Engineering CollegeVinayaka Mission Research FoundationChennai636001India Department of Mechanical Engineering Dr.M.G.R.Educational and Research InstituteChennai600095India

Biodiesel fuel is a potential alternative energy source for diesel engines due to its physiochemical characteristics relatively similar to those of traditional diesel *** this study,the performance,emission,and combustion features of a mono cylinder DI diesel engine are assessed using 20%Pumpkin seed methyl ester(PSOME20)and considering varying injection pressures(200,220,240,and 260 bar).The considered Pumpkin seed oil is converted into pumpkin biodiesel by transesterification and then used as *** findings demonstrate that the Brake Thermal Efficiency(BTE)of PSOME20 can be raised by 1.68%,and the carbon monoxide(CO),hydrocarbon(HC),and smoke emanations can be lowered,while oxides of nitrogen(NOx)emissions are increased at an injection pressure(IP)of 240 bar compared to the standard IP of 200 *** cylinder pressure and the Heat Release Rate(HRR)become higher at 240 bar,whereas the ignition delay is shortened with respect to PSOME20 at a normal IP of 200 bar.

关键词： Pumpkin seed biodiesel performance emission diesel engine injection pressure

A Review on the Precise Control of the Liquid Nitrogen Supplying System in Transonic Cryogenic Wind Tunnel

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Journal of Thermal Science 2023年第2期32卷 692-707页

作者： ZHANG Wei GAO Rong CHENG Jun CHEN Wanhua SONG Yuanjia LIAO Daxiong College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Aerodynamics Research and Development Center Mianyang 621000China

The liquid nitrogen(LN2)supplying system,one of the four key systems of the cryogenic wind tunnel(CWT),is an essential guarantee for the precise control,fast and safe regulation of the wind tunnel’s total ***,the technical schemes,advantages and disadvantages of different LN2 supplying systems are discussed and analyzed based on the operation conditions and test requirements of different ***,together with the development of the pilot cryogenic transonic wind tunnel(PCTW),the key technologies of the system,including the supplying mode,rapid and accurate regulation of injection pressure,development of large scale cryogenic centrifugal pump,and matching technology between pumps and pipe network,have been summarized and the solutions to the existing issues are ***,a supplying process suitable for large-scale CWT is proposed,which has the ability of independent commissioning,rapid regulation,accurate control of injection pressure and transient response to the wind tunnel’s wide range of working *** breakthrough in LN2 supplying system enables China to construct a CWT for the future competitive high Reynolds number aircraft.

关键词： cryogenic wind tunnel liquid nitrogen supplying system working principle injection pressure dynamic simulation

Performance,combustion,and emission characteristics of on a diesel engine fuelled with hydrogen compressed natural gas and Kusum seed biodiesel

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Waste Disposal and Sustainable Energy 2023年第2期5卷 151-163页

作者： Krishna Bharathi Parimi Bhatti Sukhvinder Kaur Sathya Vara Prasad Lankapalli Jaikumar Sagari Department of Mechanical Engineering Andhra UniversityVisakhapatnamIndia Department of Mechanical Engineering GITAM Institute of TechnologyVisakhapatnamIndia

Renewable fuels have many advantages over fossil fuels because they are biodegradable and sustainable,and help mitigate social and environmental *** objective of the present study is to evaluate the performance,combustion,and emission characteristics of a compression–ignition engine using hydrogen compressed natural gas(HCNG)-enriched Kusum seed biodiesel blend(KSOBD20).The flow rate of HCNG was set at 5 L/min,10 L/min,and 15 L/min,and the injection pressure was varied in the range of 180 bar to 240 *** thermal efficiency(BTE)and brake-specific fuel consumption(BSFC)were improved when HCNG was added to the *** characteristics,namely,cylinder pressure(CP)and net heat release rate(NHRR),were also *** of carbon monoxide(CO),hydrocarbons(HC),and smoke were also reduced,with the exception of nitrogen oxides(NO_(x)).The higher injection pressure(240 bar)had a positive effect on the operating *** an injection pressure of 240 bar,for KSOB20+15 L/min HCNG,the highest BTE and the lowest BSFC were found to be 32.09%and 0.227 kg/kWh,***,the CP and NHRR were 69.34 bar and 66.04 J/°.CO,HC,and smoke levels were finally reduced to 0.013%,47×10^(-6)and 9%,respectively,with NO_(x)levels at 1623×10^(-6).For optimum results in terms of engine characteristics,the fuel combination KSOBD20+15 L/min HCNG at FIP 240 bar is recommended.

关键词： Biodiesel Compressed natural gas injection pressure Emission Cylinder pressure Brake thermal efficiency

Study of the expansion characteristics of a pulsed plasma jet in air

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Plasma Science and Technology 2017年第4期19卷 48-61页

作者：赵雪维余永刚莽珊珊薛晓春 School of Energy and Power Engineering Nanjing University of Science and Technology Nanjing 210094 People's Republic of China School of Science Nanjing University of Science and Technology Nanjing 210094 People's Republic of China

In the background of electrothermal-chemical （ETC） emission,an investigation has been conducted on the characteristics of a freely expanding pulsed plasma jet in *** evolutionary process of the plasma jet is experimentally investigated using a piezoelectric pressure sensor and a digital high-speed video *** variation relation in the extended volume,axial displacement and radial displacement of the pulsed plasma jet in atmosphere with time under different discharge voltages and jet breaking pressures is *** on experiments,a two-dimensional axisymmetric unsteady model is established to analyze the characteristics of the two-phase interface and the variation of flow-field parameters resulting from a pulsed plasma jet into air at a pressure of 1.5-3.5 MPa under three nozzle diameters （3 mm,4 mm and 5 ram,respectively）.The images of the plasma jet reveal a changing shape process,from a quasiellipsoid to a conical head and an elongated cylindrical *** axial displacement of the jet is always larger than that along the radial *** extended volume reveals a single peak distribution with *** to the experiment,the numerical simulation agrees well with the experimental *** parameters of the jet field mutate at the nozzle exit with a decrease in the parameter pulse near the nozzle,and become more and more gradual and close to environmental *** the injection pressure and nozzle diameter can increase the parameters of the flow field such as the expansion volume of the pulsed plasma jet,the size of the Mach disk and the *** addition,the turbulent mixing in the expansion process is also enhanced.

关键词： electrothermal-chemical propulsion pulsed plasma jet injection pressure nozzlediameter experiment numerical simulation

Simulating hydraulic fracturing processes in laboratory-scale geological media using three-dimensional TOUGH-RBSN

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第6期10卷 1102-1111页

作者： Daisuke Asahina Pengzhi Pan Kimikazu Tsusaka Mikio Takeda John E.Bolander Geological Survey of Japan IbarakiJapan State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China INPEX Corporation TokyoJapan University of California DavisUSA

In this context, recent developments in the coupled three-dimensional(3 D) hydro-mechanical(HM)simulation tool TOUGH-RBSN are presented. This tool is used to model hydraulic fracture in geological media, as observed in laboratory-scale tests. The TOUGH-RBSN simulator is based on the effective linking of two numerical methods: TOUGH2, a finite volume method for simulating mass transport within a permeable medium; and a lattice model based on the rigid-body-spring network(RBSN) concept. The method relies on a Voronoi-based discretization technique that can represent fracture development within a permeable rock matrix. The simulator provides two-way coupling of HM processes, including fluid pressure-induced fracture and fracture-assisted flow. We first present the basic capabilities of the modeling approach using two example applications, i.e. permeability evolution under compression deformation, and analyses of a static fracturing simulation. Thereafter, the model is used to simulate laboratory tests of hydraulic fracturing in granite. In most respects, the simulation results meet expectations with respect to permeability evolution and fracturing patterns. It can be seen that the evolution of injection pressure associated with the simulated fracture developments is strongly affected by fluid viscosity.

关键词： Hydraulic fracture Crack opening TOUGH Rigid-body-spring network(RBSN) Permeability injection pressure Fluid viscosity Hydro-mechanical(HM) processes

A Spiral History of the Development of Ways to Identify the Correct Position of the injection Needle in Relation to the Peripheral Nerve: A Brief Historical Essay

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Open Journal of Anesthesiology 2023年第5期13卷 95-100页

作者： Valery Piacherski Lidziya Muzyka Department of Anesthesiology and Intensive Care Mogilev Regional Clinical Hospital Mogilev Belarus Department of Anesthesiology and Intensive Care Сentral District Hospital of Krugloe Krugloe Belarus Department of Anesthesiology and Intensive Care Сentral District Hospital of Belynichi Belynichi Belarus

The first way to identify the needle in relation to the peripheral nerve W. Halsted and R. Hall in 1884 performed the first regional blockade (using direct visualization). However, Vassily von Anrep was a few months earlier described the blockade of the peripheral nerve by anatomical landmarks. In 1912, the blockade of the brachial plexus was first performed using electrical stimulation, but this technique has been widely used only since 1962. The most popular way to identify the needle relative to the nerve at the moment remains US guidance. A promising direction may be optical coherence tomography. But this method is under development. In the last decade, a method for determining the pressure of a local anesthetic has been introduced into practice to determine the position of the needle relative to the nerve.

关键词： Regional Anesthesia Electrical Nerve Stimulation Ultrasound Guidance Оptical Coherence Tomography Local Anesthetic pressure injection pressure

Sand production control mechanisms during oil well production and construction

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Petroleum Research 2021年第4期6卷 361-367页

作者： Arman Salahi Ali Naghi Dehghan Seyed Jamal Sheikhzakariaee Afshin Davarpanah Department of Petroleum and Chemical Engineering Science and Research BranchIslamic Azad UniversityTehranIran Department of Mining Engineering Science and Research BranchIslamic Azad UniversityTehranIran Department of Geology Faculty of SciencesIslamic Azad UniversityScience and Research BranchTehranIran Department of Mathematics Aberystwyth UniversityAberystwythSY233BZUK

Sand production is considered as one of the significant production issues that significantly reduce wellbore *** process of sand or solids production in production operations is one of the crucial operational inefficiencies that can lead to wells ***,the drilling mud might erupt through the ***,it is essential to properly determine what types of solids or sand are produced to correctly predict efficient sand control *** paper aimed to compare different sand production control mechanisms and how to control or minimize sand ***,we consider injection pressure and sand moisture on the sand production *** to this study’s findings,pressure injection and moisture increase had caused sand production increase,which should be considered in operational ***,chemical injection such as resin and hydrogel injection usually has efficient sand production control *** expandable sand screen is an expandable three-layer component that is driven into the well and expanded.

关键词： Sand production Expandable sand screen Chemical agents injection pressure Moisture

The effect of silica nanoparticle aggregates on wax dissolution in diesel oil

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Petroleum Science 2011年第2期8卷 207-210页

作者： Sun Renyuan Wang Lei Sun Chao Lin Lei Jiang Hanqiao School of Petroleum Engineering China University of Petroleum Qingdao Shandong 266555 China Institute of Drilling ＆ Production Technology Jidong Oilfield Tangshan Hebei 063004 China Xianhe Oil Production Plant Shengli Oilfield Dongying Shandong 257000 China School of Petroleum Engineering China University of Petroleum Beijing 102249 China

In recent years, silica nanoparticle aggregates （SNPAs） have been used to decrease the injection pressure of wells in low permeability reservoirs achieving good results. In order to study the mechanisms for reduction in the injection pressure of low permeability wells by the SNPA-diesel oil system injection, the microstructure of SNPAs was observed with a transmission electron microscope （TEM）. The particle size distribution of SNPAs was also measured by the laser scattering method. The viscosities of diesel oil and SNPA-diesel oil system were measured with a capillary viscometer. The effect of SNPAs on the solubility of wax in the diesel oil was experimentally studied. The influencing factors, including temperature and SNPA concentration in diesel oil, on wax solubility were analyzed. A pore-throat film displacement model （PTFDM） was built for mechanism explanation. The microstructure and size distribution analyses show that the SNPAs are in the nanometer size range. The viscosity of the SNPA-diesel oil system is lower than that of the diesel oil. The solubility of wax in the diesel oil increases greatly due to SNPA addition, the solubility ratio reaches 7.5. The solubility of wax in diesel oil increases with increases in the concentration of SNPAs in the diesel oil and with the temperature. It is proved that the addition of SNPAs to diesel oil helps remove the wax deposited near the wellbore. This maybe one of the main mechanisms for injection pressure decreases in low permeability reservoirs.

关键词： Silica nanoparticle aggregates solubility of wax low permeability reservoir pore-throatfilm displacement model injection pressure