Analysis of the Influence of Diesel Nozzle Geometry in the Injection Rate Characteristic

Benajes, Jesús; Pastor, Javier; Payri, Raúl; Plazas, Alejandro H.

doi:10.1115/1.1637636

Cited by 104 publications

(55 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This work is focused on the effects of flow along the cylindrical and conical injector nozzles. It is reported that grid size has a significant effect on the convergence and predicted results [5,6]. Grid sensitivity is tested on the model with different grid sizes as shown in Fig.…”

Section: Resultsmentioning

confidence: 99%

“…Han et al [3] found that the primary breakup region is relatively influenced by nozzle geometry when compared to the conical and cylindrical nozzles.In addition, velocity components act on the nozzle outlet plane are significant and appreciated since it contribute to the disintegration of the mixing fluids into droplets [7]. It is reported that grid size has a significant effect on the convergence and predicted results [5,6]. Obviously, conical nozzle with k-factor of 2 generates a sharp velocity graph to represent the highest velocity at nozzle outlet compared to another two nozzle holes.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effects of Nozzle Shape on the Flow Characteristics of Premix Injector Using Computational Fluid Dynamics (CFD)

Yii

Chin

Amirnordin

et al. 2015

AMM

View full text Add to dashboard Cite

Abstract. The burner system is a patented, unique, higher-efficiency and fuel-injector system that works with a specially designed oil burner to create ultra-efficient combustion that reduces oil use, greenhouse gases and other harmful emissions. This research shows the injector nozzle geometries play a significant role in flow characteristics, atomization and formation of fuel-air mixture in order to improve combustion performance, and reducesome pollutant products from burner system. The aim of this research is to determine the effects of nozzle hole shape on flowcharacteristics of the premix injector by using CFD. Multiphase of volume of fluid (VOF) cavitating flow inside nozzles are determined by means of steady simulations and Eulerian-Eulerian two-fluid approach is used for performing mixing of Jatropha oil and air. Nozzle flow simulations resulted that cavitation area is strongly dependent on the nozzle hole shape. Conical hole with k-factor of 2 provides higher flow velocity and turbulent kinetic energy compared with conical hole with k-factor of 1.3 and cylindrical hole. The results show that the premix injector nozzle hole shape gives impact to the flowcharacteristics and indirectly affects the emission of the burner system.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effects of Nozzle Shape on the Flow Characteristics of Premix Injector Using Computational Fluid Dynamics (CFD)

Yii

Chin

Amirnordin

et al. 2015

AMM

View full text Add to dashboard Cite

show abstract

“…reduced pressure, velocity, and promotion of cavitation along the nozzle length [9]. Also the divergent nozzle has a more acute inlet angle than the non-divergent case which may lead to increased flow separation at the nozzle inlet e.g.…”

Section: Scanning Electron Microscope Analysismentioning

confidence: 99%

Characterisation of Spray Development from Spark-Eroded and Laser-Drilled Multi-Hole Injectors in an Optical DISI Engine and in a Quiescent Injection Chamber

Butcher¹,

Aleiferis²,

Richardson³

2015

SAE Technical Paper Series

View full text Add to dashboard Cite

This paper addresses the need for fundamental understanding of the mechanisms of fuel spray formation and mixture preparation in direct injection spark ignition (DISI) engines. Fuel injection systems for DISI engines undergo rapid developments in their design and performance, therefore, their spray breakup mechanisms in the physical conditions encountered in DISI engines over a range of operating conditions and injection strategies require continuous attention. In this context, there are sparse data in the literature on spray formation differences between conventionally drilled injectors by spark erosion and latest Laser-drilled injector nozzles. A comparison was first carried out between the holes of sparkeroded and Laser-drilled injectors of same nominal type by analysing their in-nozzle geometry and surface roughness under an electron microscope. Then the differences in their spray characteristics under quiescent conditions, as well as in a motoring optical engine, are discussed on the basis of highspeed imaging experiments and image processing methods. Specifically, the spray development mechanism was quantified by spray tip penetration and cone angle data under a range of representative low-load and high-low engine operating conditions (0.5 bar and 1.0 bar absolute, respectively), as well as at low and high injector body temperatures (20 °C and 90 °C) to represent cold and warm engine-head conditions. Droplet sizing was also performed with the two injectors using Phase Doppler Anemometry in a quiescent chamber.

show abstract

“…The reasons for these discrepancies are: secondary-scale effects related to micro-geometrical differences, which are caused by wall roughness [28] and by details of the nozzle geometry, such as roundness at the nozzle inlet [47,48] and nozzle conicity, or the K-factor of the hole [48,49]; local-flow motion, which is related to the influence of the viscous stresses on the tensile strength of a liquid [50,51] (the classic definition of cavitation inception is based on observations of liquid rupturing under static or quasi-static conditions [9], that is, when the static pressure in the liquid phase is much higher than the viscous stresses caused by the flow, but, if this is not the case, the tensile strength can be affected by the viscous stresses) and to the turbulent and transient nature of hydrodynamic cavitation [52][53][54][55]; liquid quality, which is characterized by means of the radius and density of the undissolved-gas microbubbles in the fluid as well as by the concentration of dissolved gas in the liquid phase [9,56]. In other words, the scale effects associated with the micro-geometry of the system, the local flow phenomena and the liquid quality should have a negligible effect on the considered tests in order to make equation (2.1) valid.…”

Section: Application Of Hydrodynamic Similarity To Cavitating Flows Imentioning

confidence: 99%

Fluid dynamics of acoustic and hydrodynamic cavitation in hydraulic power systems

Ferrari¹

2017

Proc. R. Soc. A.

View full text Add to dashboard Cite

Cavitation is the transition from a liquid to a vapour phase, due to a drop in pressure to the level of the vapour tension of the fluid. Two kinds of cavitation have been reviewed here: acoustic cavitation and hydrodynamic cavitation. As acoustic cavitation in engineering systems is related to the propagation of waves through a region subjected to liquid vaporization, the available expressions of the sound speed are discussed. One of the main effects of hydrodynamic cavitation in the nozzles and orifices of hydraulic power systems is a reduction in flow permeability. Different discharge coefficient formulae are analysed in this paper: the Reynolds number and the cavitation number result to be the key fluid dynamical parameters for liquid and cavitating flows, respectively. The latest advances in the characterization of different cavitation regimes in a nozzle, as the cavitation number reduces, are presented. The physical cause of choked flows is explained, and an analogy between cavitation and supersonic aerodynamic flows is proposed. The main approaches to cavitation modelling in hydraulic power systems are also reviewed: these are divided into homogeneous-mixture and twophase models. The homogeneous-mixture models are further subdivided into barotropic and baroclinic models. The advantages and disadvantages of an implementation of the complete Rayleigh-Plesset equation are examined.

show abstract

Analysis of the Influence of Diesel Nozzle Geometry in the Injection Rate Characteristic

Cited by 104 publications

References 16 publications

Effects of Nozzle Shape on the Flow Characteristics of Premix Injector Using Computational Fluid Dynamics (CFD)

Effects of Nozzle Shape on the Flow Characteristics of Premix Injector Using Computational Fluid Dynamics (CFD)

Characterisation of Spray Development from Spark-Eroded and Laser-Drilled Multi-Hole Injectors in an Optical DISI Engine and in a Quiescent Injection Chamber

Fluid dynamics of acoustic and hydrodynamic cavitation in hydraulic power systems

Contact Info

Product

Resources

About