A study on the injection characteristics of a liquid-phase liquefied petroleum gas injector for air-fuel ratio control

2005 ◽  
Vol 219 (8) ◽  
pp. 1037-1046 ◽  
Author(s):  
Hansub Sim ◽  
Kangyoon Lee ◽  
Namhoon Chung ◽  
Myoungho Sunwoo
Keyword(s):  
Liquid Phase ◽  
Fuel Injection ◽  
Injection Pressure ◽  
Vapour Phase ◽  
Injection Rate ◽  
Injection System ◽  
Driving Voltage ◽  
Liquefied Petroleum Gas ◽  
Fuel Temperature ◽  
Fuel Ratio

Liquefied petroleum gas (LPG) is widely used as a gaseous fuel in spark ignition engines because of its considerable advantages over gasoline. However, the LPG engine suffers a torque loss because the vapour-phase LPG displaces a larger volume of air than do gasoline droplets. In order to improve engine power as well as fuel consumption and air-fuel ratio control, considerable research has been devoted to improving the LPG injection system. In the liquid-phase LPG injection systems, the injection rate of an injector is affected by the fuel temperature, injection pressure, and driving voltage. When injection conditions change, the air-fuel ratio should be accurately controlled in order to reduce exhaust emissions. In this study, correction factors for the fuel injection rate are developed on the basis of fuel temperature, injection pressure, and injector driving voltage. A compensation method to control the amount of injected fuel is proposed for a liquid-phase LPG injection control system. The experimental results show that the liquid-phase LPG injection system works well over the entire range of engine speeds and load conditions, and the air-fuel ratio can be accurately controlled by using the proposed compensation algorithm.

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

2004 ◽  
Vol 126 (1) ◽  
pp. 63-71 ◽  
Author(s):  
J. Benajes ◽  
J. V. Pastor ◽  
R. Payri ◽  
A. H. Plazas
Keyword(s):  
Fuel Injection ◽  
Injection Pressure ◽  
Injection Rate ◽  
Operating Conditions ◽  
Injection System ◽  
Nozzle Geometry ◽  
Flow Conditions ◽  
Test Rig ◽  
Specific Test ◽  
Nozzle Geometries

An experimental research study was carried out to analyze the influence of different orifice geometries (conical and cylindrical) on the injection rate behavior of a Common-Rail fuel injection system. For that purpose, injection tests in two different injection test rigs were conducted. This behavior of the injection rate in the different nozzles was characterized by using the non-dimensional parameters of cavitation number (K), discharge coefficient (Cd) and Reynolds number (Re). First, some relevant physical properties of the injected fuel were accurately characterized (density, kinematic viscosity and sound speed in the fluid) in a specific test rig as a function of the operating conditions (pressure and temperature). The behavior of both nozzles was analyzed at maximum injector needle lift under steady flow conditions in a cavitation test rig. Injection pressure and pressure at the nozzle discharge were controlled in order to modify the flow conditions. In addition, the nozzles were characterized in real unsteady flow conditions in an injection-rate test rig. From the raw results, the values of the relevant parameters were computed, and the occurrence of cavitation was clearly identified. The results evidenced interesting differences in the permeability of both nozzle geometries and a clear resistance of the conical nozzle to cavitation.

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.

Experimental investigation of dwell time characteristics in high-pressure double-solenoid-valve fuel injection system

2019 ◽  
Vol 233 (13) ◽  
pp. 3281-3292
Author(s):  
Dan Xu ◽  
Qing Yang ◽  
Xiaodong An ◽  
Baigang Sun ◽  
Dongwei Wu ◽  
...  
Keyword(s):  
Fuel Injection ◽  
Injection Pressure ◽  
Solenoid Valve ◽  
Injection System ◽  
Fuel Injection System ◽  
Pilot Injection ◽  
Main Injection ◽  
Injection Interval ◽  
The Difference ◽  
Variation Rule

The double-solenoid-valve fuel injection system consists of an electronic unit pump and an electronic injector. It can realize the separate control of fuel supply and injection and has the advantages of adjusting pressure by cycle and flexible controlling of the injection rate. The interval angle between the pilot and main injection directly affects the action degree and the characteristics of two adjacent injections, affecting engine performance. This work realizes multiple injection processes on the test platform of a high-pressure double-solenoid-valve fuel injection system, with maximum injection pressure reaching 200 MPa. In this study, the interval between driven current signal of pilot injection termination and that of main injection initiation is defined as the signal interval (DT1), whereas the interval between pilot injection termination and main injection initiation is defined as the injection interval (DT2). The differences between the signal and the injection intervals are calculated, and the variation rule of the difference with respect to the signal interval is analyzed. Results show that the variation rule of the difference with the signal interval first decreases, then increases, and finally decreases. The variation rule of the delay angle from the start of needle movement to the start of fuel injection is found to be the root cause of this rule. The influence of the injection pressure on needle deformation and fuel flow rate of the nozzle results in the variation rule. In addition, the influence of the cam speed, temperature, and pipe length on the difference between the signal and injection interval is determined. This research provides guidance for an optimal control strategy of the fuel injection process.

scholarly journals A Study of Combustion Characteristics of Two Gasoline–Biodiesel Mixtures on RCEM Using Various Fuel Injection Pressures

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3265
Author(s):  
Ardhika Setiawan ◽  
Bambang Wahono ◽  
Ocktaeck Lim
Keyword(s):  
Heat Release ◽  
Ignition Delay ◽  
Fuel Injection ◽  
Injection Pressure ◽  
Fuel Mixture ◽  
Injection Rate ◽  
Injection Duration ◽  
Late Start ◽  
Fuel Injection Rate ◽  
Injection Pressures

Experimental research was conducted on a rapid compression and expansion machine (RCEM) that has characteristics similar to a gasoline compression ignition (GCI) engine, using two gasoline–biodiesel (GB) blends—10% and 20% volume—with fuel injection pressures varying from 800 to 1400 bar. Biodiesel content lower than GB10 will result in misfires at fuel injection pressures of 800 bar and 1000 bar due to long ignition delays; this is why GB10 was the lowest biodiesel blend used in this experiment. The engine compression ratio was set at 16, with 1000 µs of injection duration and 12.5 degree before top dead center (BTDC). The results show that the GB20 had a shorter ignition delay than the GB10, and that increasing the injection pressure expedited the autoignition. The rate of heat release for both fuel mixes increased with increasing fuel injection pressure, although there was a degradation of heat release rate for the GB20 at the 1400-bar fuel injection rate due to retarded in-cylinder peak pressure at 0.24 degree BTDC. As the ignition delay decreased, the brake thermal efficiency (BTE) decreased and the fuel consumption increased due to the lack of air–fuel mixture homogeneity caused by the short ignition delay. At the fuel injection rate of 800 bar, the GB10 showed the worst efficiency due to the late start of combustion at 3.5 degree after top dead center (ATDC).

Microscopic Spray Characteristics of Biodiesels Derived From Karanja, Jatropha, and Waste Cooking Oils

2020 ◽  
Vol 142 (12) ◽  
Author(s):  
Chetankumar Patel ◽  
Joonsik Hwang ◽  
Choongsik Bae ◽  
Rashmi A. Agarwal ◽  
Avinash Kumar Agarwal
Keyword(s):  
Fuel Injection ◽  
Direct Injection ◽  
Injection Pressure ◽  
Axial Direction ◽  
Waste Cooking Oil ◽  
Injection System ◽  
Ambient Atmosphere ◽  
Ambient Conditions ◽  
Spray Characteristics ◽  
Spray Droplets

Abstract This study aims to assess the microscopic characteristics of Jatropha, Karanja, and Waste cooking oil-based biodiesels vis-a-vis conventional diesel under different ambient conditions in order to understand the in-cylinder processes, while using biodiesels produced from different feedstocks in the compression ignition engines. All test-fuels were injected in ambient atmosphere using a common-rail direct injection (CRDI) fuel injection system at a fuel injection pressure (FIP) of 40 MPa. Microscopic spray characteristics were measured using phase Doppler interferometer (PDI) in the axial direction of the spray at a distance of 60–90 mm downstream of the nozzle and at 0 to 3-mm distance from the central axis in the radial direction. All biodiesels exhibited relatively larger Sauter mean diameter (SMD) of the spray droplets and higher droplet velocities compared to baseline mineral diesel, possibly due to relatively higher fuel viscosity and surface tension of biodiesels. It was also observed that SMD of the spray droplets decreased with increasing distance in the radial and axial directions and the same trend was observed for all test-fuels.

scholarly journals Experimental Methodology and Facility for the J69-Engine Performance and Emissions Evaluation Using Jet A1 and Biodiesel Blends

Energies ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 4530 ◽  
Author(s):  
Gabriel Talero ◽  
Camilo Bayona-Roa ◽  
Giovanny Muñoz ◽  
Miguel Galindo ◽  
Vladimir Silva ◽  
...  
Keyword(s):  
Fossil Fuels ◽  
Fuel Injection ◽  
Engine Performance ◽  
Injection Pressure ◽  
Experimental Tests ◽  
Experimental Methodology ◽  
Injection System ◽  
Small Scale ◽  
Gas Temperature ◽  
Maximum Increase

Aeronautic transport is a leading energy consumer that strongly contributes to greenhouse gas emissions due to a significant dependency on fossil fuels. Biodiesel, a substitution of conventional fuels, is considered as an alternative fuel for aircrafts and power generation turbine engines. Unfortunately, experimentation has been mostly limited to small scale turbines, and technical challenges remain open regarding operational safety. The current study presents the facility, the instrumentation, and the measured results of experimental tests in a 640 kW full-scale J69-T-25A turbojet engine, operating with blends of Jet A1 and oil palm biodiesel with volume contents from 0% to 10% at different load regimes. Findings are related to the fuel injection system, the engine thrust, and the emissions. The thrust force and the exhaust gas temperature do not expose a significant variation in all the operation regimes with the utilization of up to 10% volume content of biodiesel. A maximum increase of 36% in fuel consumption and 11% in injection pressure are observed at idle operation between B0 and B10. A reduction of the CO and HC emissions is also registered with a maximum variation at the cruise regime (80% Revolutions Per Minute—RPM).

Simulation and Experimental Analysis of Diesel Fuel-Injection Systems With a Double-Stage Injector

1999 ◽  
Vol 121 (2) ◽  
pp. 186-196 ◽  
Author(s):  
A. E. Catania ◽  
C. Dongiovanni ◽  
A. Mittica ◽  
C. Negri ◽  
E. Spessa
Keyword(s):  
Fuel Injection ◽  
Injection Rate ◽  
Operating Conditions ◽  
Flow Coefficient ◽  
Injection System ◽  
System Component ◽  
Local Pressure ◽  
Pump Speed ◽  
Minor Losses ◽  
Set Up

A double-spring, sacless-nozzle injector was fitted to the distributor-pump fuel-injection system of an automotive diesel engine in order to study its effect on the system performance for two different configurations of the pump delivery valve assembly with a constant-pressure valve and with a reflux-hole valve, respectively. Injection-rate shapes and local pressure time histories were both numerically and experimentally investigated. The NAIS simulation program was used for theoretical analysis based on a novel implicit numerical algorithm with a second-order accuracy and a high degree of efficiency. The injector model was set up and stored in a library containing a variety of system component models, which gave a modular structure to the computational code. The program was also capable of simulating possible cavitation propagation phenomena and of taking the fluid property dependence on pressure and temperature, as well as flow shear and minor losses into account. The experimental investigation was performed on a test bench under real operating conditions. Pressures were measured in the pumping chamber at two different pipe locations and in the injector nozzle upstream of the needle-seat opening passage. This last measurement was carried out in order to determine the nozzle-hole discharge flow coefficient under nonstationary flow conditions, which was achieved for the first time in a sacless-nozzle two-stage injector over a wide pump-speed range. The numerical and experimental results were compared and discussed.

Dynamic Modeling and Identification of an Electric-Hydraulic Controlled Fuel Injection System

2014 ◽  
Vol 918 ◽  
pp. 206-211
Author(s):  
Ya Wei Lee
Keyword(s):  
Fuel Injection ◽  
Moving Average ◽  
Injection Pressure ◽  
Injection System ◽  
Autoregressive Moving Average ◽  
Heavy Vehicles ◽  
Engine Operation ◽  
Operational Mechanism ◽  
Fuel Rate ◽  
And Performance

Fuel consumption, related to engine operation and performance, has always been emphasized in the modern design of heavy vehicles. For identifying the operational mechanism of a novel hydraulically actuated electronic unit injection (HEUI) system from the viewpoint of energy conversion, this study presents the estimation of a nonlinear autoregressive moving average with exogenous inputs (NARMAX) models. By this modeling approach, the correlation between injection pressure and fuel rate under normal operations is detected. When mapping the NARMAX models into the frequency domain, the frequency response functions (FRFs) representing the energy transfer mechanisms in the system can then be precisely obtained. Due to the high-order FRFs responsible for the non-linear coupling between the various input spectral components, the HEUI dynamics can be demonstrated as an energy resonance of 22.5 Hz.

A High-Pressure Pulsed Water Jet Cutting System by Means of Water Hammer in a Convergent Pipeline

2003 ◽  
Author(s):  
Koji Yamane ◽  
Hiromitsu Sasaki ◽  
Yuzuru Shimamoto
Keyword(s):  
High Pressure ◽  
Fuel Injection ◽  
Injection Pressure ◽  
Water Jet ◽  
Injection System ◽  
Source Pressure ◽  
Electromagnetic Valve ◽  
Water Jet Cutting ◽  
Pulsed Water Jet ◽  
Cutting System

One of the authors has developed a high-pressure fuel injection system using an oil hammer for diesel engines in 1993. In the present study, we applied this novel principle of the fuel injection system to the water-jet cutting system, and a pulsed water jet cutting system by means of water hammer in convergent pipeline caused by strong spool acceleration was developed. The system consisted of a pump having a small size plunger and spool, a convergent pipeline, and automatic injector having a hole-type nozzle with a small orifice. This pump, generating strong compression waves at the convergent pipeline inlet by strong acceleration of spool and plunger, is controlled by the low source oil pressure and electromagnetic valve. The wave propagated in the convergent pipeline is dynamically intensified by water hammering in the pipeline. High pressure is then developed at the nozzle. The injection pressure and injection frequency are fully controllable by the source pressure, and by the valve-opening frequency of the electromagnetic valve (EMPV). A computer simulation demonstrated that an operation and the injection pressure are satisfactory as a water jet cutting system. It is shown that a pressure of 140 MPa is obtained in nozzle inlet by a source pressure of 11.8MPa in experiments. The dimension of the nozzle orifice was determined by visualizing the spray origin using a laser-sheet imaging technique. Stagnation force and its spectrum of water jet on work was measured to evaluate effects of injection period and standoff distance on punching time and area. Practical feasibility of water jet cutting system was demonstrated by cutting/punching tests for soft/no-heating materials or metal plates and by paint removing tests.

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