Predicting Diesel Injector Nozzle Flow Characteristics

2004 ◽  
Author(s):  
Aditya Mulemane ◽  
Ming-Chia Lai
Keyword(s):  
Flow Characteristics ◽  
Nozzle Flow ◽  
Injector Nozzle

The Sensitivity of Inner Nozzle Flow in Gasoline Direct Injection Injector to the Nozzle Geometry Parameters

2019 ◽  
Vol 141 (6) ◽  
Author(s):  
Xinhai Li ◽  
Yong Cheng ◽  
Xiaoyan Ma ◽  
Xue Yang
Keyword(s):  
Structural Parameters ◽  
Direct Injection ◽  
Large Diameter ◽  
Small Diameter ◽  
Flow Characteristics ◽  
Gasoline Direct Injection ◽  
Nozzle Geometry ◽  
Nozzle Flow ◽  
Nozzle Length ◽  
Injector Nozzle

The inner-flow of gasoline direct injection (GDI) injector nozzles plays an important role in the process of spray, and affects the mixture process in gasoline engine cylinder. The nozzle structure also affects the inner-flow of GDI injector. In order to obtain uniform performance of GDI injector, the size consistency of injector nozzle should be ensured. This paper researches the effect of nozzle length and diameter on the inner flow and analyzes the sensitivity of inner flow characteristics to these structural parameters. First, this paper reveals the process of inception, development, and saturated condition of cavitation phenomenon in injector nozzle. Second, the inner-nozzle flow characteristics are more sensitive to small diameter than large diameter under the short nozzle length, while the sensitivity of the inner-nozzle flow characteristics to large nozzle diameter becomes strong as the increase of the nozzle length. Finally, the influence of nozzle angle on the injection mass flow is studied, and the single nozzle fuel mass will increase as the decrease of nozzle angle α. And the sensitivity of inner-flow characteristic to nozzle angle becomes strong as the decrease of α.

scholarly journals Effects of Nozzle Diameter on the Spray Characteristics of Premix Injector in Burner System

2015 ◽  
Vol 773-774 ◽  
pp. 570-574
Author(s):  
Shahrin Hisham Amirnordin ◽  
Salwani Ismail ◽  
Ronny Yii Shi Chin ◽  
Norani Mansor ◽  
Mas Fawzi ◽  
...  
Keyword(s):  
Flow Characteristics ◽  
Nozzle Geometry ◽  
Nozzle Flow ◽  
Mixture Formation ◽  
Spray Characteristics ◽  
Injector Nozzle ◽  
Discrete Phase ◽  
Computational Fluid Dynamics Cfd ◽  
Steady Simulation ◽  
Two Fluid

An essential component of the injector nozzle geometry is to see the results spray atomization and mixture formation of the fuel-air combustion to improve performance, and reduce pollution from a burner. Studies involving the injectors in the combustion burner are still in a small proportion, particularly in the premix injector type. Thus, this study involves the efforts to determine the appropriate diameter of the premix injector where the injector spray characteristics is produced by using Computational Fluid Dynamics (CFD). Multiphase of the volume of fluid (VOF) cavitations flow in the nozzle is determined through steady simulation while Eulerian-Eulerian two-fluid approach is used for performing mixing of Jatropha oil and air. Further simulation is conducted using a spray with a discrete phase injection at the outflow hole injector nozzle. The investigation involves the modification of nozzle geometry on three different sizes of 0.8 mm, 1.0 mm and 1.5 mm with the analysis focused on nozzle flow characteristics of the injector. The results indicate that a small changes in injector gives high impact to the spray and combustion of a burner. This shows the importance of nozzle dimensions which influences the nozzle flow and affects the spray characteristics, hence influence the combustion and emission of the burner system.

Diesel Spray Rate-of-Momentum Measurement Uncertainties and Diagnostic Considerations

2014 ◽  
Author(s):  
Benjamin W. Knox ◽  
Michael J. Franze ◽  
Caroline L. Genzale
Keyword(s):  
Force Measurement ◽  
Control Volume ◽  
Flow Characteristics ◽  
Fuel Temperature ◽  
Integrated Electronics ◽  
Injector Nozzle ◽  
Fuel Delivery ◽  
Discharge Velocity ◽  
The Face ◽  
Measurement Uncertainties

Interpretation of combustion and emissions outcomes in diesel engines is often enhanced by accurate knowledge of the transient fuel delivery rate and flow characteristics of the injector nozzle. Important physical characteristics of these flows, including velocity profile and flow separation or cavitation effects, are difficult to measure directly, but can be characterized from a flow-averaged perspective through the measurement of nozzle flow coefficients, namely the discharge, velocity, and area contraction coefficients. Both the transient fuel mass flow rate and the flow-averaged nozzle coefficients can be found by measuring the mass and momentum flux of the fuel stream leaving the nozzle during injection through the application of an impingement technique, where fuel is sprayed onto the face of a transducer calibrated for force measurement in close proximity to the nozzle. While several published experiments have employed the spray impingement method to quantify rate-of-injection, the experimental setup and equipment selections vary widely and may contribute to disagreements in measured rate-of-injection. This paper identifies and provides estimates of measurement uncertainties that can arise when employing different experimental setups using the impingement method. It was observed that the impingement technique was sensitive to the design of the strike cap, specifically the contact area between the cap and transducer diaphragm, in addition to fuel temperature. Conversely, we observed that the impingement technique was relatively insensitive to angular and vertical misalignment, where the uncertainty can be estimated using control volume analysis. Transducer selection, specifically those with low acceleration sensitivity, high resonant frequency, and integrated electronics piezoelectric circuitry substantially reduce the noise in the measurement.

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

2015 ◽  
Vol 773-774 ◽  
pp. 450-454
Author(s):  
Ronny Yii Shi Chin ◽  
Shahrin Hisham Amirnordin ◽  
Amir Khalid
Keyword(s):  
Flow Characteristics ◽  
Fuel Injector ◽  
Spray Characteristics ◽  
Hole Shape ◽  
Injector Nozzle ◽  
K Factor ◽  
Efficient Combustion ◽  
Nozzle Hole ◽  
Nozzle Geometries ◽  
Air Nozzle

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 spray characteristics, atomization and formation of fuel-air mixture in order to improve combustion performance, and decrease some pollutant products from burner system. The aim of this research is to determine the effects of nozzle hole shape on spray characteristics 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 spray characteristics and indirectly affects the emission of the system.

scholarly journals Study on the Common Rail Type Injector Nozzle Design Based on the Nozzle Flow Model

2020 ◽  
Vol 10 (2) ◽  
pp. 549
Author(s):  
Sang-Wook Han ◽  
Yun-Sub Shin ◽  
Hyun-Chul Kim ◽  
Gee-Soo Lee
Keyword(s):  
Flow Model ◽  
Injection Pressure ◽  
Common Rail ◽  
Injection System ◽  
Nozzle Flow ◽  
Flow Area ◽  
Common Rail Injection System ◽  
Injection Duration ◽  
Injector Nozzle ◽  
Cavitation Region

In this paper, a nozzle flow model was used to design an injector nozzle and obtain initial spray conditions for the dimethyl ether (DME) common rail-injection system. In order to deliver the same amount of energy as that provided by diesel at a low injection pressure of 50 MPa, the injector for DME needs nozzle holes with larger diameters and a higher SAC volume for the same injection duration. In addition, the needle lift and needle seat diameter should be increased to maintain a minimum flow area ratio. Although the vapour pressure and maximum injection pressure of DME are lower than those of diesel, the nozzle in a DME system showed higher discharge coefficients and effective nozzle exit diameters for the same injection duration owing to low kinematic viscosity. However, because the maximum injection pressure in DME is lower than that with diesel, and the length of the cavitation region is narrower.

Injector Nozzle Multiphase Flow Numerical Simulation of High Pressure Common Rail System

2014 ◽  
Vol 1008-1009 ◽  
pp. 1006-1010
Author(s):  
Yan Hu ◽  
Guo Xiu Li
Keyword(s):  
Numerical Simulation ◽  
High Pressure ◽  
Multiphase Flow ◽  
Volume Fraction ◽  
Flow Characteristics ◽  
Common Rail ◽  
Injector Nozzle ◽  
Short Period ◽  
Nozzle Structure ◽  
High Pressure Common Rail

The changing of injector nozzle structure will influence the combustion and emission properties in diesel engine. Three-dimensional numerical simulation of multiphase flow of mini-sac nozzles of high pressure common rail were calculated by using the computational fluid dynamics ( CFD ) method in this paper. The results shown that this method can be more accurately obtained a lot of useful information on the flow field inside the nozzle in a relatively short period of time, and it is convenient for analysis and research the influence of geometry parameters on the flow characteristics inside the nozzle. The paper also studied the influence of nozzle inlet pressure, the angle between the axis of the hole and the axis of the injector and nozzle entrance radius to the flow characteristics inside the nozzle. It also studied the distribution of internal pressure, velocity of flow, gas-phase volume fraction and turbulent kinetic energy. These studies provided a favorable basis for the design and improvement of the nozzle structure and optimize combustion system matches.

Visual experiment of transient cavitating flow characteristics in the real-size diesel injector nozzle

2016 ◽  
Vol 78 ◽  
pp. 13-20 ◽  
Author(s):  
Zhixia He ◽  
Zhengyang Zhang ◽  
Genmiao Guo ◽  
Qian Wang ◽  
Xianying Leng ◽  
...  
Keyword(s):  
Flow Characteristics ◽  
Cavitating Flow ◽  
The Real ◽  
Injector Nozzle ◽  
Real Size
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