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.

Integrated Modelling of Fuel Influence on Common Rail Injection System Performance

2006 ◽  
Author(s):  
O. Chiavola ◽  
F. Palmieri ◽  
G. Chiatti
Keyword(s):  
Flow Rate ◽  
Injection Pressure ◽  
Common Rail ◽  
Injection System ◽  
Integrated Modelling ◽  
Nozzle Flow ◽  
Common Rail System ◽  
Local Flow ◽  
Common Rail Injection System ◽  
Common Rail Injection

A model for the analysis of diesel engine common rail injection system has been developed and the influence that different fuels have on the injection performances has been investigated. Diesel fuel, biodiesel and kerosene have been used and the differences of injection flow rate, injection pressure time trace, nozzle flow features and break up mechanism have been highlighted. The coupling of two different codes has been used in the simulations: the former one, AMESim code, has been adopted to model the common rail system and to investigate the fuel flow rate and the injection pressure dependence on the fuel type. The latter computational tool, FIRE code, has been initialized by means of the results obtained from the injection system simulation and has been used to perform the 3D investigation of the internal nozzle flow and of the spray formation phenomena, aimed at evaluating the effect of physical fuel features on local flow characteristics and their influence on the system performances. Details of the adopted modeling strategy are described and results of each simulation step are presented.

scholarly journals Theoretical study to determine the proper injection system for upgrading fuel system of diesel engine om357 to common rail system

2018 ◽  
Vol 7 (4) ◽  
pp. 2594
Author(s):  
Razieh Pourdarbani ◽  
Ramin Aminfar
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Engine Performance ◽  
Injection Pressure ◽  
Common Rail ◽  
Injection System ◽  
Injection Timing ◽  
Common Rail System ◽  
Common Rail Injection System ◽  
Multi Stage

In this research, we tried to investigate all the fuel injection systems of diesel engines in order to select the most suitable fuel injection system for the OM357 diesel engine to achieve the highest efficiency, maximize output torque and reduce emissions and even reduce fuel consumption. The prevailing strategy for this study was to investigate the effect of injection pressure changes, injection timing and multi-stage injection. By comparing the engines equipped with common rail injection system, the proposed injector for engine OM357 is solenoid, due to the cost of this type of injector, MAP and controller (ECU). It is clear that this will not be possible only with the optimization of the injection system, and so other systems that influence engine performance such as the engine's respiratory system and combustion chamber shape, etc. should also be optimized. 

Investigation of the Influence of Injection Rate Shaping on the Spray Characteristics in a Diesel Common Rail System Equipped with a Piston Amplifier

2005 ◽  
Vol 127 (6) ◽  
pp. 1102-1110 ◽  
Author(s):  
J. Benajes ◽  
R. Payri ◽  
S. Molina ◽  
V. Soare
Keyword(s):  
Cone Angle ◽  
Injection Pressure ◽  
Injection Rate ◽  
Common Rail ◽  
Injection System ◽  
Common Rail System ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Common Rail Injection System ◽  
Common Rail Injection

The quality of the mixing process of fuel and air in a direct injection diesel engine relies heavily on the way the spray develops when injected into the combustion chamber. Among other factors, the spray development depends on the injection rate of the fuel delivered by the injector. The paper presents a study, at both a macroscopic and microscopic level, of a Diesel spray generated by a common-rail injection system featuring a piston pressure amplifier. By modifying the timing and the duration of the injector and amplifier piston actuation, it is possible to obtain high injection pressures up to 180MPa, and different shapes for the injection rate, which would not be achievable with a regular common rail injection system. The spray evolution produced by three different injection rate shapes (square, ramp, and boot) has been investigated in an injection test rig, by means of visualization and PDPA techniques, at different injection conditions. The main conclusions are the important effect on spray penetration of the initial injection rate evolution and the small influence of the maximum injection pressure attained at the end of the injection event. Smaller or even negligible effects have been found on the spray cone angle and on the droplet Sauter mean diameter.

scholarly journals Experimental study on injection characteristics of diesel-bioethanol fuel blends

2015 ◽  
Vol 161 (2) ◽  
pp. 28-32
Author(s):  
Stasys Slavinskas ◽  
Tomas Mickevičius
Keyword(s):  
Diesel Fuel ◽  
Injection Pressure ◽  
Injection Rate ◽  
Injection System ◽  
Common Rail Injection System ◽  
Fuel Blends ◽  
Injection Duration ◽  
Common Rail Injection ◽  
Ethanol Blends ◽  
Bioethanol Fuel

This article presents the test results of injection processes of diesel-bioethanol fuel blends on a high pressure common rail injection system. The injection characteristics were analyzed using the injection rate measuring instrumentation. The injection rate, cycle injection quantity, injection delay and injection duration were analyzed across a range of injection pressure and injection energizing time. As the results show, the peak injection rate and delay of diesel-ethanol blends are lower compared to diesel fuel. The injection duration and discharge coefficients of diesel-ethanol blends were lower than those of diesel fuel. It was observed that fuel density and fuel viscosity have significant influence on the injection characteristics.

scholarly journals Effect of the In-Cylinder Back Pressure on the Injection Process and Fuel Flow Characteristics in a Common-Rail Diesel Injector Using GTL Fuel

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 452
Author(s):  
Luka Lešnik ◽  
Breda Kegl ◽  
Eloísa Torres-Jiménez ◽  
Fernando Cruz-Peragón ◽  
Carmen Mata ◽  
...  
Keyword(s):  
Diesel Fuel ◽  
Back Pressure ◽  
Common Rail ◽  
Fuel Properties ◽  
Injection System ◽  
Nozzle Flow ◽  
Average Mass ◽  
Injection Process ◽  
Fuel Flow ◽  
Computational Program

The presented paper aims to study the influence of mineral diesel fuel and synthetic Gas-To-Liquid fuel (GTL) on the injection process, fuel flow conditions, and cavitation formation in a modern common-rail injector. First, the influence on injection characteristics was studied experimentally using an injection system test bench, and numerically using the one-dimensional computational program. Afterward, the influence of fuel properties on internal fuel flow was studied numerically using a computational program. The flow inside the injector was considered as multiphase flow and was calculated through unsteady Computational Fluid Dynamics simulations using a Eulerian–Eulerian two-fluid approach. Finally, the influence of in-cylinder back pressure on the internal nozzle flow was studied at three distinctive back pressures. The obtained numerical results for injection characteristics show good agreement with the experimental ones. The results of 3D simulations indicate that differences in fuel properties influence internal fuel flow and cavitation inception. The location of cavitation formation is the same for both fuels. The cavitation formation is triggered regardless of fuel properties. The size of the cavitation area is influenced by fuel properties and also from in-cylinder back pressure. Higher values of back pressure induce smaller areas of cavitation and vice versa. Comparing the conditions at injection hole exit, diesel fuel proved slightly higher average mass flow rate and velocities, which can be attributed to differences in fluid densities and viscosities. Overall, the obtained results indicate that when considering the injection process and internal nozzle flow, GTL fuel can be used in common-rail injection systems with solenoid injectors.

scholarly journals Organization of Six-Cylinder Tractor Diesel Working Process

2021 ◽  
Vol 20 (5) ◽  
pp. 427-433
Author(s):  
G. M. Kuharonak ◽  
M. Klesso ◽  
A. Predko ◽  
D. Telyuk
Keyword(s):  
Combustion Chamber ◽  
Fuel Injection ◽  
Injection Pressure ◽  
Common Rail ◽  
Injection System ◽  
Fuel Injection System ◽  
Rotary Valve ◽  
Original Design ◽  
Working Process ◽  
Common Rail System

The purpose of the work is to consider the organization of the working process of six-cylinder diesel engines with a power of 116 and 156 kW and exhaust gas recirculation. The following systems and components were used in the experimental configurations of the engine: Common Rail BOSСH accumulator fuel injection system with an injection pressure of 140 MPa, equipped with electro-hydraulic injectors with seven-hole nozzle and a 500 mm3 hydraulic flow; direct fuel injection system with MOTORPAL fuel pump with a maximum injection pressure of 100 MPa, equipped with MOTORPAL and AZPI five-hole nozzle injectors; two combustion chambers with volumes of 55 and 56 cm3 and bowl diameters of 55.0 and 67.5 mm, respectively; cylinder heads providing a 3.0–4.0 swirl ratio for Common Rail system, 3.5–4.5 for mechanical injection system. The recirculation rate was set by gas throttling before the turbine using a rotary valve of an original design. The tests have been conducted at characteristic points of the NRSC cycle: minimum idle speed 800 rpm, maximum torque speed 1600 rpm, rated power speed 2100 rpm. It has been established that it is possible to achieve the standards of emissions of harmful substances: on the 116 kW diesel engine using of direct-action fuel equipment and a semi-open combustion chamber; on the 156 kW diesel using Common Rail fuel supply system of the Low Cost type and an open combustion chamber.

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