scholarly journals Idling Performance under Valve Deactivation Strategy in Port Fuel Injection Engine

2019 ◽  
Vol 16 (4) ◽  
pp. 7155-7169
Author(s):  
A. S. Paimon ◽  
S. Rajoo ◽  
W. Jazair ◽  
M. A. Abas ◽  
Z. H. Che Daud
Keyword(s):  
Coefficient Of Variation ◽  
Engine Speed ◽  
Fuel Injection ◽  
Swirl Flow ◽  
Combustion Stability ◽  
Cylinder Pressure ◽  
Fuel Injector ◽  
Port Fuel Injection ◽  
Indicated Mean Effective Pressure ◽  
Significant Difference

This paper investigates the effect of valve deactivation (VDA) on idling performance in port fuel injection (PFI) engine. The test was conducted on 1.6L, 4-cylinder engine with PFI configuration. One of the two intake valves in each cylinder was deactivated (zero lift on deactivated port) and fuel injector was modified to only provide fuel spray on the active intake port. In-cylinder pressure was recorded by the combustion analyzer in order to measure and analyze the combustion characteristics. From the test, there are up to 6% of fuel consumption improvements across all the test conditions. Better combustion stability is achieved at very low idling speed (throttle position, TP = 2%) as a lower coefficient of variation of engine speed (COVrpm) and coefficient of variation indicated mean effective pressure (COVimep) were recorded. Increased intake velocity and swirl flow in the VDA strategy creates more turbulence intensity causing higher heat release rate and faster combustion. However, there is no significant difference in the pumping work during the intake cycle but there is extra pumping work recorded towards the end of expansion stroke due to the very early end of combustion. Therefore, valve deactivation strategy provides limited positive improvement to the idling performance in PFI engine.

On-Board Indicated Pressure and Torque Estimation in Engines With a High Number of Cylinders

2002 ◽  
Author(s):  
Enrico Corti ◽  
Davide Moro
Keyword(s):  
Control Strategy ◽  
Engine Speed ◽  
Fuel Injection ◽  
Control Strategies ◽  
Engine Control ◽  
Cylinder Pressure ◽  
Signal Processing Algorithm ◽  
Operating Condition ◽  
Torque Estimation ◽  
Speed Fluctuations

In recent years engine control development focused the attention on torque-based models, that allow improving driveability and implementing traction control strategies. The design of such a torque-based engine control strategy requires the knowledge of the torque produce by the engine, which depends on fuel injection time, spark advance, throttle opening, EGR command, … In the actual engine control strategies this is mainly done by means of static maps stored in the ECU memory. The real engine torque production under every operating condition can be evaluated by means of the in-cylinder pressure estimation, thus allowing a torque based closed loop control strategy. Many approaches are present in the literature showing the possibility of on-board estimating the actual torque produced by the engine not simply by using static maps, but estimating it through other measured signals. Most of the methodologies that do not require a specific sensor placed on the engine are based either on the engine speed fluctuations (measured by a pick-up facing the flywheel teeth) or on the engine block vibrations (measured by the knock sensor), performing better for engines with a low number of cylinders. The paper presents an original methodology based on the instantaneous engine speed fluctuations, that has been usefully applied to engines with higher number of cylinders. The methodology is based on the observation of the speed fluctuations in a crankshaft window inside the expansion stroke and on the hypothesis that there exists a strong correlation between these engine speed fluctuations and pressure inside the selected cylinder. This relationship has been characterized using Frequency Response Functions (FRF) for each steady-state engine operating condition. In the following the FRFs have been used to perform in-cylinder pressure and then indicated torque estimation under every operating condition, and a specific signal processing algorithm has been developed in order to apply the procedure during speed and load engine transients. The experimental tests have been conducted mounting a six-cylinder turbo-charged spark-ignited engine in a test cell. The application on-board a vehicle of the same methodology seems to be feasible due to the quickness of the algorithm employed and the presence on-board of all the sensors required for the implementation.

Model Predictive Engine Speed Control for Transmissions With Dog Clutches

2016 ◽  
Author(s):  
Qilun Zhu ◽  
Robert Prucka ◽  
Michael Prucka ◽  
Hussein Dourra
Keyword(s):  
Engine Speed ◽  
Speed Control ◽  
Cost Effective ◽  
Combustion Stability ◽  
Design Parameters ◽  
Shift Quality ◽  
Engine Model ◽  
Prediction Horizon ◽  
Indicated Mean Effective Pressure ◽  
The Impact

The need for cost-effective fuel economy improvements has driven the introduction of automatic transmissions with an increasing number of gear ratios. Incorporation of interlocking dog clutches in these transmissions decreases package space and increases efficiency, as compared to conventional dry or wet clutches. Unlike friction based clutches, interlocking dog clutches require very precise rotational speed matching prior to engagement. Precise engine speed control is therefore critical to maintaining high shift quality. This research focuses on controlling the engine speed during a gearshift period by manipulating throttle position and combustion phasing. Model predictive control (MPC) is advantageous in this application since the speed profile of a future prediction horizon is known with relatively high confidence. The MPC can find the optimal control actions to achieve the designated speed target without invoking unnecessary actuator manipulation and violating hardware and combustion constraints. This research utilizes linear parameter varying (LPV) MPC to control the engine speed during the gearshift period. Combustion stability constraints are considered with a control oriented covariance of indicated mean effective pressure model (COV of IMEP). The proposed MPC engine speed controller is validated with a high-fidelity 0-dimensional engine model with crank angle resolution. Four case studies, based on simulation, investigate the impact of different MPC design parameters. They also demonstrate that the proposed MPC engine controller successfully achieves the speed reference tracking objective while considering combustion variation constraints.

Studies of Swirl Burner Characteristics, Flame Lengths and Relative Pressure Amplitudes

2011 ◽  
Vol 133 (10) ◽  
Author(s):  
A. Valera-Medina ◽  
N. Syred ◽  
P. Bowen ◽  
A. Crayford
Keyword(s):  
High Speed ◽  
Fossil Fuels ◽  
Fuel Injection ◽  
Flame Length ◽  
Swirl Flow ◽  
High Speed Photography ◽  
Relative Pressure ◽  
Fuel Injector ◽  
Swirl Burner ◽  
Potential Oscillations

Swirl stabilized combustion is a technology which, for stationary combustion, consumes more than 70 to 80% of the world’s fossil fuels. There have been many reviews of this technology, but there are still many gaps in understanding. This paper focuses on the general characteristics of a 100kW swirl burner, originally designed for poor quality fuels, in terms of flame characteristic, length and pressure fluctuations, to give a relative measure of the propensity of the system to respond to outside perturbations. Studied effects include swirl number, symmetry of the swirl flow system, type of fuel injector and mode of fuel injection. A range of techniques, including High Speed Photography (HSP), Particle Image Velocimetry (PIV) and fluctuating pressure measurements were used to create flame maps, flame length detail, and relative pressure amplitudes graphs. The results are discussed in the context of potential oscillations and coupling mechanisms including the effect of the precessing vortex core (PVC), recirculation and shear flow instabilities.

scholarly journals Real-Time Monitoring of Combustion Instability in a Homogeneous Charge Compression Ignition (HCCI) Engine Using Cycle-by-Cycle Exhaust Temperature Measurements

2012 ◽  
Author(s):  
David P. Gardiner ◽  
W. Stuart Neill ◽  
Wallace L. Chippior
Keyword(s):  
Real Time ◽  
Fuel Injection ◽  
Combustion Instability ◽  
Temperature Measurements ◽  
Cylinder Pressure ◽  
Hcci Engine ◽  
Exhaust Temperature ◽  
Indicated Mean Effective Pressure ◽  
Test Engine ◽  
Reference Measurements

This paper describes an experimental study concerning the feasibility of monitoring the combustion instability levels of an HCCI engine based upon cycle-by-cycle exhaust temperature measurements. The test engine was a single cylinder, four-stroke, variable compression ratio Cooperative Fuel Research (CFR) engine coupled to an eddy current dynamometer. A rugged exhaust temperature sensor equipped with special signal processing circuitry was installed near the engine exhaust port. Reference measurements were provided by a laboratory grade, water-cooled cylinder pressure transducer. The cylinder pressure measurements were used to calculate the Coefficient of Variation of Indicated Mean Effective Pressure (COV of IMEP) for each operating condition tested. Experiments with the HCCI engine confirmed that cycle-by-cycle variations in exhaust temperature were present, and were of sufficient magnitude to be captured for processing as high fidelity signal waveforms. There was a good correlation between the variability of the exhaust temperature signal and the COV of IMEP throughout the operating range that was evaluated. The correlation was particularly strong at the low levels of COV of IMEP (2–3%), where production engines would typically operate. A real-time combustion instability signal was obtained from cycle-by-cycle exhaust temperature measurements, and used to provide feedback to the fuel injection control system. Closed loop operation of the HCCI engine was achieved in which the engine was operated as lean as possible while maintaining the COV level at or near 2.5%.

Determination of Static and Dynamic Injection Characteristics of a Common-Rail Direct Injection Diesel Engine Fuelled by CME-Diesel Blends

2017 ◽  
Author(s):  
Ervin Santos ◽  
Edwin Quiros
Keyword(s):  
Fuel Injection ◽  
Electronic Control Unit ◽  
Direct Injection ◽  
The Philippines ◽  
Common Rail ◽  
Injection Timing ◽  
Fuel Injector ◽  
Alternative Source ◽  
Injection Parameters ◽  
Significant Difference

Much interest is given to the research in biodiesel these days. It is renewable and has similar properties to conventional diesel. Biodiesel is also generally seen to produce less emissions, hence it is seen as an attractive and a greener alternative source of energy. Biodiesels are also referred to as Fatty Acid Methyl Esters (FAME). They are obtained from the transesterification of oils from organic products such as animal fat or vegetable oil. Common biodiesel feedstocks are soybean (USA), rapeseed (Europe), palm, and coconut (Asia). The Philippines, being one of the largest producers of coconut in the world, should have a substantial interest in this. Biodiesel in the Philippines is obtained from coconut oil and is commonly called Coconut Methyl Ester (CME). There is a number of research works available that study the effects of biodiesel when used to run diesel engines, although there is notably less studies on CME and particularly Philippine-CME available. This work aims to show the fuel injection timing and duration of a Common Rail Direct Injection (CRDI) engine run by CME-diesel with neat diesel as baseline. There are two sets of injection parameters that describe the injection behaviour of an engine. The static injection parameters refer to the electronic commands given out by the Electronic Control Unit (ECU) while the dynamic injection parameters refer to the actual physical injection happening in the fuel injector nozzle. Knowledge of these information may help explain possible differences in performance and/or emissions observed in biodiesel-fed engines. The static injection commands were obtained by tapping into the solenoid signal wire from the ECU. The dynamic injection parameters were estimated from line pressure signals in the fuel injection line. All the tests were done on the AVL Eddy Current Engine Dynamometer in the University of the Philippines Vehicle Research and Testing Laboratory. Baseline data were recorded from 100% neat diesel, then volumetric blends B10 (10% CME biodiesel and 90% neat diesel) and B20 (20% CME biodiesel and 80% neat diesel) were mixed for the tests. The CRDI engine was ran at full load, sweeping the operating range at 400 RPM increments from 800 to 4000. The results showed no significant difference in the static injection parameters of the CME-diesel blend-fed engines as compared to being ran with neat diesel. As for the dynamic injection parameters, there were some significant differences observed in the higher engine speeds starting at 2800 RPM. The observed changes were attributed to the differences in the physiochemical properties of CME biodiesel as compared to neat diesel.

scholarly journals Cyclic Pressure Variations in A Small Diesel Engine Fueled with Biodiesel and Antioxidant Blends

2020 ◽  
Vol 17 (2) ◽  
pp. 7851-7857
Author(s):  
M.H. Ali ◽  
A. Abdullah ◽  
M.H. Mat Yasin ◽  
M.K. Kamarulzaman
Keyword(s):  
Diesel Engine ◽  
Engine Speed ◽  
Load Condition ◽  
Combustion Characteristics ◽  
Dual Fuel ◽  
Biodiesel Fuel ◽  
Cylinder Pressure ◽  
Indicated Mean Effective Pressure ◽  
Engine Combustion ◽  
Cyclic Variations

Biodiesel fuel is considered as one of the most competence sustainable replacement for fossil fuel due to their superior combustion characteristics and possesses higher oxygen content. Thus, many researchers recently investigated to improve biodiesel capability by adding additives whether by blending with dual-fuel or tri-fuel. However, the combustion characteristics for biodiesel and biodiesel-additives blends are not thoroughly examined and need additional research works to study how the biodiesel behaviour and characterise. Thus, this research main objective is to study a single-cylinder diesel engine cyclic cylinder pressure variations running with biodiesel with antioxidant (B2HA1.0 and B2HT 1.0) blends with palm oil methyl ester (POME). While The baseline fuels used for this study were biodiesel (B20) and pure diesel (B0). The entire test fuels were examined at a constant engine speed 1800 rpm with 100% engine load condition. The engine combustion characteristics were studied by utilising the indicated mean effective pressure (IMEP) and cyclic variations of combustion pressure at 200 consecutive cycles. Combustion characteristics of engine diesel have been studied by using statistical analysis. The results revealed that the engine running with biodiesel-antioxidants have higher cyclic variations of combustion from B20 and B0, which B2HA1.0 possessed the highest cyclic variations. It can be summarised from the study that biodiesel-antioxidants fuels produce a substantial influence on the engine cyclical variation, which linked to the characteristics of the engine combustion.

Experimental Investigation of Spray and Combustion Performances of a Fuel-Staged Low Emission Combustor: Part II — Effects of Venturi Angle

2018 ◽  
Author(s):  
Cunxi Liu ◽  
Fuqiang Liu ◽  
Jinhu Yang ◽  
Yong Mu ◽  
Gang Xu
Keyword(s):  
Flow Field ◽  
High Altitude ◽  
Gas Turbines ◽  
Fuel Injection ◽  
Operating Conditions ◽  
Combustion Stability ◽  
Main Stage ◽  
Fuel Injector ◽  
Lean Burn ◽  
Low Emission

In order to reduce NOx emissions, modern gas turbines are often equipped with lean burn combustion systems, where the high-velocity fuel-lean conditions that limit NOx formation in combustors also inhibit the ability of ignition, high altitude relight, and lean combustion stability. To face these issues, an internally staged scheme of fuel injection is proposed. The pilot and main fuel staging enable fuel distribution control and high turn-down ratio, multi-injections of main fuel leads to a fast and efficient fuel/air mixing. A fuel-staged low emission combustor in the framework of lean burn combustion is developed in the present study, the central pilot stage of fuel injector working singly at low power operating conditions is swirl-cup prefilming atomization and main stage is jet-in-crossflow multi-injection atomization, a combination of pilot and main stage injection is provided for higher power operating conditions. A significant amount of the air mass flow utilised for fuel preparation and initiation is adverse to the operability specifications, such as ignition, lean blow-out, and high-altitude relight etc. The spray characteristics of pilot spray and flow field are one of the key factors affecting combustion operability. This work investigates the effects of the venturi angle on combustion operability, the ignition and lean blow-out performances were evaluated in a single dome rectangular combustor. Furthermore, the spray patterns and flow field are characterized by kerosene-planar laser induced fluorescence and particle image velocimetry to provide insight into the correlation between spray, flow field and combustion operability performances.

Preliminary Study of Low Emission Gas Turbine Combustor With Airblast Fuel Atomizer

1976 ◽  
Vol 98 (1) ◽  
pp. 15-22
Author(s):  
K. Yamanaka ◽  
K. Nagato
Keyword(s):  
Gas Turbine ◽  
Fuel Injection ◽  
Tube Wall ◽  
Combustion Stability ◽  
Exhaust Emission ◽  
Fuel Injector ◽  
Gas Turbine Combustor ◽  
Low Emission ◽  
New Type ◽  
Preliminary Study

Recent papers describe that an airblast fuel atomizer is very effective for reducing emissions from a gas turbine and this type of fuel injector is being applied to practical engines. This paper deals with the new type of airblast fuel atomizer AFIT which comes from “Airblast Fuel Injection Tube” that makes fuel to break up into droplets by atomizing air at several small holes on the tube wall and fuel is well mixed with atomizing air instantly at the exits of holes. Regarding this AFIT, the fuel spray characteristics, combustion stability which is usually narrow for the combustor with an airblast fuel atomizer at lower engine speeds and exhaust emission levels are experimented and its effectiveness is discussed.

scholarly journals The Performance of a Reverse Flow Combustor Using JP 10 Fuel

1986 ◽  
Author(s):  
J. Winter ◽  
K. H. Maden
Keyword(s):  
Fuel Injection ◽  
Reverse Flow ◽  
Combustion Stability ◽  
Fuel Injector ◽  
Test Rig ◽  
Comparative Performance ◽  
Aviation Kerosene ◽  
Exhaust Temperature ◽  
Pure Hydrocarbon ◽  
Tube Metal

The test rig performance of a fan spray fuel injection reverse flow combustor for a 500 shp engine using JP 10 fuel is compared with that using aviation kerosene, (Avtur). JP 10 fuel is a pure hydrocarbon with a hydrogen content of 11.8% compared with some 13.8% for aviation kerosene. The comparative performance data reported include fuel injector atomisation characteristics, exhaust combustion efficiencies and emmissions, exhaust temperature distributions, flame tube metal temperatures and simulated pressure altitude relight and combustion stability over a range of conditions up to a simulated altitude of 6,1 km.

Experimental Study of Low Temperature Diesel Combustion Sensitivity to Engine Operating Parameters

2012 ◽  
Vol 134 (8) ◽  
Author(s):  
G. P. McTaggart-Cowan ◽  
S. Cong ◽  
C. P. Garner ◽  
E. Wahab ◽  
M. Peckham
Keyword(s):  
Low Temperature ◽  
Engine Speed ◽  
Fuel Injection ◽  
Fractional Factorial ◽  
Combustion Stability ◽  
Small Scale ◽  
Operating Parameters ◽  
Diesel Combustion ◽  
Injection Quantity ◽  
Charge Temperature

This work elucidated which engine operating parameters have the greatest influence on Low temperature diesel combustion (LTC) and emissions. Key parameters were selected and evaluated at low and intermediate speed and load conditions using fractional factorial and Taguchi orthogonal experimental designs. The variations investigated were: about ± 5% in EGR rate, fuel injection quantity and engine speed respectively; and ± 10 °C in intake charge temperature. The half-fractional factorial results showed that the interactions among these parameters were negligible for a specific load/speed point. The Taguchi orthogonal method could be used as an efficient DoE tool for studying the multi-parameter ‘small-scale transients’ that a diesel engine would be likely to encounter when operating in LTC modes. LTC showed the most significant sensitivity to EGR rate variations, where an increase from 60% to 63% in EGR rate doubled THC and CO emissions and reduced combustion stability. LTC was also sensitive to the fuel injection quantity with an increase in injected mass lowering the overall oxygen-fuel ratio and thereby increasing THC and CO emissions. These two parameters influenced the oxygen concentration in the intake charge; which was identified to be a decisive parameter for the LTC combustion and emissions. Intake charge temperature affected the total charge quantity trapped in the cylinder and showed noticeable influence on CO emissions for the low speed intermediate load condition. Variations in engine speed showed a negligible influence on the LTC combustion processes and emissions.

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