Research on Control System of Quasi-Homogeneous Lean-Burn Engine

2014 ◽  
Vol 496-500 ◽  
pp. 1248-1251 ◽  
Author(s):  
Jia Jun Wang ◽  
Jun Wei Tao ◽  
Hong Da Zhang ◽  
Jin Bo Guo
Keyword(s):  
Control System ◽  
Fuel Injection ◽  
Injection Timing ◽  
Engine Fuel ◽  
Lean Burn ◽  
Engine Control System ◽  
Lean Combustion ◽  
Combustion Technology ◽  
Fuel Consumption And Emissions ◽  
Injection Pulse

Quasi-homogeneous lean mixture combustion technology can take full advantages of lean-combustion, and help reduce the engine fuel consumption and emissions. Quasi-Homogeneous Lean-burn engine Control System, combined virtual instruments with engine electronic control technology, can precisely control air-fuel ratio injection, timing, fuel injection pulse and ignite on timing, which provides a reliable and convenient platform for the engine lean-burning performance tests..

Research of Working Mode Conversion Based on GDI Engine

2015 ◽  
Vol 741 ◽  
pp. 546-549
Author(s):  
Ying Jie Sun ◽  
Yang Li ◽  
Chun Yu Wang ◽  
Yao Chun Li ◽  
Yun Feng Liang
Keyword(s):  
Pulse Width ◽  
Fuel Injection ◽  
Mode Conversion ◽  
Linear Interpolation ◽  
Homogeneous Mixture ◽  
Injection Timing ◽  
Lean Burn ◽  
Crank Angle Degree ◽  
Crank Angle ◽  
Injection Pulse

This paper designs the control strategy of working mode conversion from stoichiometric homogeneous mixture to lean homogeneous mixture. First of all, after the types and parameters of electric hardware were selected in this system, a complete circuit layout of engine control system was designed, which used microcontroller named MC9S12XDP512 as control chip and the test bench was built. Then, we adjust the fuel injection pulse width and throttle opening to realize lean burn (lambda = 1.4) of torque being 40N.m at speed of 2500 r / min, and adjust injection timing to find the best injection timing which is 350 crank angle degree, and adjust the ignition advance angle to find the best ignition advance angle which is 13 crank angle degree. Finally, the work mode conversion was completed by the optimal parameters linear interpolation, reducing the fuel injection pulse width and increasing the throttle opening at the same time.

The Research of Lean Combustion Characteristic of Compound Injection System of Direct Injection Engine

2014 ◽  
Vol 532 ◽  
pp. 362-366 ◽  
Author(s):  
Jiang Feng Mou ◽  
Rui Qing Chen ◽  
Yi Wei Lu
Keyword(s):  
Gasoline Engine ◽  
Direct Injection ◽  
Injection System ◽  
Intake Manifold ◽  
Combustion Characteristic ◽  
Injection Timing ◽  
Mixed Gas ◽  
Lean Burn ◽  
Direct Injection Engine ◽  
Lean Combustion

This paper studies the lean burn limit characteristic of the compound injection system of the direct-injection gasoline engine. The low pressure nozzle on the intake manifold can achieve quality homogeneous lean mixture, and the direct injection in the cylinder can realized the dense mixture gas near the spark plug. By adjusting the two injection timing and injection quantity, and a strong intake tumble flow with special shaped combustion chamber, it can produces the reverse tumble to form different hierarchical levels of mixed gas in the cylinder. Experimental results show: the compound combustion system to the original direct-injection engine lean burn limit raise 1.8-2.5 AFR unit.

Effect of Split Injection Timing on Combustion and Emissions of a DISI Optical Engine Under Lean Burn Condition

2020 ◽  
Author(s):  
Zhe Sun ◽  
Mingli Cui ◽  
Hongyu Wang ◽  
Mohamed Nour ◽  
Xuesong Li ◽  
...  
Keyword(s):  
High Energy ◽  
Flame Speed ◽  
Operating Conditions ◽  
Image Processing Technique ◽  
Injection Timing ◽  
Split Injection ◽  
Lean Burn ◽  
Combustion Performance ◽  
Optical Engine ◽  
Lean Combustion

Abstract Lean combustion has proven to be an effective way to improve the efficiency and emissions of the direct injection spark ignition (DISI) engine. However, one of the main problems at the lean stability limit is the major decrease in flame temperature due to dilution, resulting in a low laminar flame speed, especially under low-speed engine operating conditions. The split injection is a potential technology to realize proper air-fuel mixing and achieve different spray distribution that can help in solving such problems. In this study, split injections with different secondary injection timings were tested to achieve homogeneous and homogeneous-stratified modes in a DISI optical engine under lean-burn mode. The split ratio of each strategy was 1:1. The engine was operated at 800 rpm, and a high-energy ignition system was utilized to realize lean combustion at a lambda of 1.55. Engine combustion performance and emissions were tested while performing high-speed color recording to study the characteristics of flame chemiluminescence through a quartz piston combined with a 45-degree mirror installed below. Flame structure during various combustion phases was compared under different selected conditions based on a digital image processing technique. The results show that the pressure and emissions vary with the second injection timing. Proper control of the split injection timing can improve lean combustion performance, including faster flame speed, increased indicated mean effective pressure (IMEP), and lower harmful emissions. Poor fuel evaporation and soot generation from spatial hot spots in the combustion process of split injection are the major challenges for further improvement.

Distribution of Two-Stage Direct Injection CNG-Air Mixture near Lean Limit Using CFD

2013 ◽  
Vol 465-466 ◽  
pp. 448-452
Author(s):  
Mas Fawzi ◽  
Bukhari Manshoor ◽  
Yoshiyuki Kidoguchi ◽  
Yuzuru Nada
Keyword(s):  
Fuel Injection ◽  
Direct Injection ◽  
Engine Performance ◽  
Injection Pressure ◽  
Gas Jet ◽  
Exhaust Emission ◽  
Injection Technique ◽  
Injection Timing ◽  
Two Stage ◽  
Lean Burn

Previous work shows that gas-jet ignition with two-stage injection technique is effective to extend lean combustible ranges of CNG engines. In this report, the robustness of the gas-jet ignition with two-stage injection method was investigated purposely to improve the performance of a lean burn direct injection CNG engine. The experiment was conducted using an engine at speed of 900 rpm, fuel-injection-pressure of 3MPa, equivalence ratio at 0.8, and ignition timing at top dead center. The effect of first injection timing on the test engine performance and exhaust emission was analyzed. First injection timings near the gas-jet ignition produced unstable combustion with occurrence of misfires except at a timing which produced distinctively good combustion with low HC and CO emissions. Computational fluid dynamics was used to provide hindsight of the fuel-air mixture distribution that might be the cause of misfires occurrence at certain injection timings.

scholarly journals A Numerical Study on the Pilot Injection Conditions of a Marine 2-Stroke Lean-Burn Dual Fuel Engine

Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1396
Author(s):  
Hao Guo ◽  
Song Zhou ◽  
Jiaxuan Zou ◽  
Majed Shreka
Keyword(s):  
Natural Gas ◽  
Fuel Injection ◽  
Numerical Study ◽  
Pollutant Emissions ◽  
Dual Fuel ◽  
Injection Timing ◽  
Pilot Injection ◽  
Lean Burn ◽  
Injection Duration ◽  
Pilot Fuel

The global demand for clean fuels is increasing in order to meet the requirements of the International Maritime Organization (IMO) of 0.5% global Sulphur cap and Tier III emission limits. Natural gas has begun to be popularized on liquefied natural gas (LNG) ships because of its low cost and environment friendly. In large-bore marine engines, ignition with pilot fuel in the prechamber is a good way to reduce combustion variability and extend the lean-burn limit. However, the occurrence of knock limits the increase in power. Therefore, this paper investigates the effect of pilot fuel injection conditions on performance and knocking of a marine 2-stroke low-pressure dual-fuel (LP-DF) engine. The engine simulations were performed under different pilot fuel parameters. The results showed that the average in-cylinder temperature, the average in-cylinder pressure, and the NOx emissions gradually decreased with the delay of the pilot injection timing. Furthermore, the combustion situation gradually deteriorated as the pilot injection duration increased. A shorter pilot injection duration was beneficial to reduce NOx pollutant emissions. Moreover, the number of pilot injector orifices affected the ignition of pilot fuel and the flame propagation speed inside the combustion chamber.

Development of a Small Aviation Two-stroke Kerosene Engine Fuel Injection Controller

2019 ◽  
Vol 13 ◽  
Author(s):  
Linlin Chen ◽  
Qun Sun ◽  
Weidong Gao ◽  
Chong Wang
Keyword(s):  
Numerical Calculation ◽  
Numerical Model ◽  
Electromagnetic Interference ◽  
Fuel Injection ◽  
Assembly Language ◽  
Bench Test ◽  
Engine Fuel ◽  
Pulse Spectrum ◽  
Initial Injection ◽  
Injection Pulse

Background: The study of kerosene fuel for gasoline engines is of great significance to the supply, management, storage and transportation of military fuel, as well as its safety. Small aviation two-stroke kerosene engine fuel injection controller is the key technology of kerosene engines. It is very important to improve the performance of kerosene engine by controlling the air-fuel ratio accurately Objective: The initial injection pulse spectrum was firstly obtained by numerical calculation in the absence of kerosene injection pulse spectrum, and then the injection controller was designed based on the initial injection pulse spectrum. Methodology:: Firstly, a numerical model of the whole engine was established by using BOOST software. The air mass flow data of the inlet was obtained through numerical calculation. The amount of initial engine fuel injection was calculated according to the requirements of air-fuel ratios in each working condition, from which an initial injection pulse spectrum was obtained. Then, based on Freescale 16-bit embedded micro-controller MC9S12DP512, a kerosene engine fuel injection controller was developed, together with the circuit was also designed. According to the initial fuel injection pulse spectrum, a two-dimensional interpolation algorithm was developed by using assembly language and C language mixed programming, and the anti-electromagnetic interference ability of the controller was further enhanced. Finally, the accuracy of the initial injection pulse spectrum and the performance and reliability of the injection controller of the kerosene engine were verified by the kerosene engine bench test. Conclusion: The experimental results show that the numerical model was accurate, and the development time of the injection controller was shortened by using the numerical model to calculate the initial injection pulse spectra. The developed controller was stable and reliable, which can meet the control requirement.

Research on Signal Simulator at Crankshaft of Motorcycle Gasoline Engine

2012 ◽  
Vol 614-615 ◽  
pp. 414-421
Author(s):  
Chang Sheng Wang ◽  
Tie Zao Yang ◽  
Haijun Zhang ◽  
Hong Jie Zhao
Keyword(s):  
Control System ◽  
Pulse Width ◽  
High Speed ◽  
Gasoline Engine ◽  
Fuel Injection ◽  
Position Sensor ◽  
Operational Environment ◽  
Development Platform ◽  
Injection Pulse ◽  
Motorcycle Engine

Cam signals, crankshaft signals and angle signals were simulated by analogue crankshaft position sensors developed by C8051F series micro processors to emulate the operational environment of motorcycle engine. In the software development platform of gasoline engine, software running status of control system was tested. MP424 high-speed sampling card was applied to actually observe properties of ignition advance angle and fuel injection advance angle. The experiment suggested that practically observed fuel injection pulse width, ignition pulse width, properties of ignition advance angle and fuel injection advance angle were the same as those of models of control system software. This proved that the analogue crankshaft position sensor that has been developed is practical and feasible.

Visualization study of natural gas direct injection combustion

2003 ◽  
Vol 217 (8) ◽  
pp. 667-676 ◽  
Author(s):  
Z Huang ◽  
S Shiga ◽  
T Ueda ◽  
H Nakamura ◽  
T Ishima ◽  
...  
Keyword(s):  
Natural Gas ◽  
High Speed ◽  
Fuel Injection ◽  
Single Injection ◽  
Direct Injection ◽  
Video Camera ◽  
Injection Timing ◽  
Lean Combustion ◽  
High Speed Video Camera ◽  
Wrinkled Flame

A visualization study of natural gas direct injection combustion was carried out by using a high speed video camera. The results show that the distribution of the stratified mixture di ers with the injection mode, with parallel and single injection tending to form a higher degree of mixture stratification than opposed injection. Flame propagates toward the downstream direction in the cases of parallel and single-injection combustion, and flame propagates outward from the centre of the combustion chamber in the case of opposed injection combustion. A characteristic of turbulent combustion with a wrinkled flame front is presented in natural gas direct injection combustion. Super-lean combustion can be realized owing to the formation of an ignitable stratified mixture with the optimum setting of the fuel injection timing.

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