Effects of injection timing and rail pressure on combustion characteristics and cyclic variations of a common rail DI engine fuelled with F-T diesel synthesized from coal

Abstract A fuel blend consisting of 10% S8 by mass (a Fischer-Tropsch synthetic kerosene), and 90% ULSD (Ultra Low Sulfur Diesel) was investigated for their combustion characteristics and impact on emissions during RCCI (Reactivity Controlled Compression Ignition) combustion in a single cylinder experimental engine utilizing a 65% by mass n-butanol port fuel injection (PFI). RCCI is a dual fuel combustion strategy achieved with the introduction of a PFI fuel of the low-reactive n-butanol, and a direct injection (DI) of a high-reactivity blend (FT-BLEND) into an experimental diesel engine. The combustion analysis and emissions testing were conducted at 1500 RPM at an engine load of 5 bar IMEP (Indicated Mean Effective Pressure), and CA50 of 9° ATDC (After Top Dead Center); CDC (Conventional Diesel Combustion) and RCCI with 65Bu-35ULSD were utilized as the baseline for AHRR (Apparent Heat Release Rate), ringing and emissions comparisons. It was found during a preliminary investigation with a Constant Volume Combustion Chamber (CVCC) that the introduction of 10% by mass S8 into a mixture with 90% ULSD by mass only increased Derived Cetane Number (DCN) by 0.8, yet it was found to have a significant effect on the combustion characteristics of the fuel blend. This led to the change in injection timing necessary for maintaining 65Bu-35F-T BLEND RCCI at a CA50 of 5° ATDC (After Top Dead Center) to be shifted 3° closer to TDC, thus affecting the Ringing Intensity (RI), Pressure Rise Rate, and heat release of the blend all to decrease. CDC was conducted with a primary injection of 14° BTDC at a rail pressure of 800 bar, all RCCI testing was conducted with 65% PFI of n-butanol by mass and 35% DI, to prevent knock, with a rail pressure of 600 bar and a pilot injection of 60° BTDC for 0.35 ms. 65Bu-35ULSD RCCI was conducted with a primary injection at 6° BTDC with neat ULSD#2, the fuel 65Bu-35F-T BLEND in RCCI had a primary injection at 3° BTDC to maintain CA50 at 9° ATDC. 65Bu-35ULSD RCCI experienced a NOx and soot emissions decrease of 40.8% and 91.44% respectively in comparison to CDC. The fuel 65Bu-35F-T BLEND in RCCI exhibited an additional decrease of NOx and soot of 32.9 and 5.3%, in comparison to 65Bu-35ULSD RCCI for an overall decrease in emissions of 73.7% and 96.71% respectively. Ringing Intensity followed a similar trend with reductions in RI for 65Bu-35ULSD RCCI decreasing only by 6.2% whereas 65Bu-35F-T BLEND had a decrease in RI of 76.6%. Although emissions for both RCCI fuels experienced a decrease in NOx and soot in comparison to CDC, UHC and CO did increase as a result of RCCI. CO emissions for 65Bu-35ULSD RCCI and 65Bu-35F-T BLEND where increased from CDC by a factor of 5 and 4 respectively with UHC emissions rising from CDC by a factor of 3.4. The fuel 65Bu-35F-T BLEND had a higher combustion efficiency than 65Bu-35ULSD in RCCI at 91.2% due to lower CO emissions of the blend.

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Adaptation of Water Emulsified Fuel by the Common Rail Pressure and Injection Timing

The Proceedings of Conference of Kyushu Branch ◽

10.1299/jsmekyushu.2017.70.209 ◽

2017 ◽

Vol 2017.70 (0) ◽

pp. 209

Author(s):

Kenta YAMADA ◽

Atsuyoshi TAKAYAMA ◽

Yusei MUROYA ◽

Keisuke MATSUNAGA

Keyword(s):

Common Rail ◽

Injection Timing ◽

Rail Pressure ◽

Emulsified Fuel ◽

Common Rail Pressure ◽

The Common

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Experimental and numerical investigation of injection timing and rail pressure impact on combustion characteristics of a diesel engine

Energy Conversion and Management ◽

10.1016/j.enconman.2019.02.039 ◽

2019 ◽

Vol 185 ◽

pp. 730-739 ◽

Cited By ~ 16

Author(s):

Filip Jurić ◽

Zvonimir Petranović ◽

Milan Vujanović ◽

Tomaž Katrašnik ◽

Rok Vihar ◽

...

Keyword(s):

Diesel Engine ◽

Numerical Investigation ◽

Combustion Characteristics ◽

Injection Timing ◽

Rail Pressure ◽

Pressure Impact

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Development and Demonstration of Control Strategies for a Common Rail Direct Injection Armoured Fighting Vehicle Engine

Defence Science Journal ◽

10.14429/dsj.67.11450 ◽

2017 ◽

Vol 67 (4) ◽

pp. 382

Author(s):

Jensen Samuel J. ◽

Paul Pramod M. ◽

A. Ramesh ◽

Anand Mammen Thomas ◽

V. Ramanujachari ◽

...

Keyword(s):

Engine Speed ◽

Control Strategies ◽

Common Rail ◽

Coolant Temperature ◽

Injection Timing ◽

Boost Pressure ◽

Rail Pressure ◽

Control Software ◽

Testing Facility ◽

Engine Testing

<p class="Abstract">The development of a controller which can be used for engines used in armoured fighting vehicles is discussed. This involved choosing a state of the art reference common rail automotive Diesel engine and setting-up of a transient engine testing facility. The dynamometer through special real-time software was controlled to vary the engine speed and throttle position. The reference engine was first tested with its stock ECU and its bounds of operation were identified. Several software modules were developed in-house in stages and evaluated on special test benches before being integrated and tested on the reference engine. Complete engine control software was thus developed in Simulink and flashed on to an open engine controller which was then interfaced with the engine. The developed control software includes strategies for closed loop control of fuel rail pressure, boost pressure, idle speed, coolant temperature based engine de-rating, control of fuel injection timing, duration and number of injections per cycle based on engine speed and driver input. The developed control algorithms also facilitated online calibration of engine maps and manual over-ride and control of engine parameters whenever required. The software was further tuned under transient conditions on the actual engine for close control of various parameters including rail pressure, idling speed and boost pressure. Finally, the developed control strategies were successfully demonstrated and validated on the reference engine being loaded on customised transient cycles on the transient engine testing facility with inputs based on military driving conditions. The developed controller can be scaled up for armoured fighting vehicle engines.</p>

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Injection control strategy of diesel engine based on speed segment PID and operating parameter adaptation

Journal of Computational Methods in Sciences and Engineering ◽

10.3233/jcm-215378 ◽

2021 ◽

pp. 1-18

Author(s):

Guojin Chen ◽

Jiawen Wang ◽

Chang Chen ◽

Yiming Yuan ◽

Long Xu

Keyword(s):

Diesel Engine ◽

Fuel Injection ◽

Operating Parameter ◽

Common Rail ◽

Injection System ◽

Injection Timing ◽

Engine Fuel ◽

Rail Pressure ◽

Injection Quantity ◽

Injection Control

Aiming at the problems of low precision, poor anti-interference and poor follow-up in the control parameters for the diesel engine fuel injection system, this paper studies the control method of the high-pressure common rail electronic control fuel injection system of the diesel engine, constructs the high-pressure common rail fuel injection control system based on the ECU, and establishes the speed segment PID control model of fuel injection quantity, common rail pressure, fuel injection timing and fuel injection rate by using MATLAB/Simulink. The fuel injection quantity and timing are simulated. In order to realize all-round and flexible control of the diesel engine under different working conditions, and to achieve the desired optimal performance in all aspects, the optimization control method of the injection law for the diesel engine is studied. The diesel engine fuel injection control strategy based on speed segment PID and operating parameter adaptation is proposed to realize precise control of the common rail pressure, injection quantity, injection timing and injection rate under different working conditions. The simulation calculation and bench test show that the maximum fluctuation of rail pressure at idle speed is only 5 MPa, and the time to reach stability is only 1.25 s, which greatly improves the control accuracy, anti-interference and follow-up ability of the injection parameters.

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Spray and Combustion Characteristics of Biodiesel Fuel in a Direct Injection Common-Rail Diesel Engine

ASME/IEEE 2007 Joint Rail Conference and Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/jrc/ice2007-40082 ◽

2007 ◽

Cited By ~ 1

Author(s):

Hyun Kyu Suh ◽

Hyun Gu Rho ◽

Chang Sik Lee

Keyword(s):

Diesel Engine ◽

Diesel Fuel ◽

Direct Injection ◽

Injection Rate ◽

Combustion Characteristics ◽

Common Rail ◽

Biodiesel Fuel ◽

Injection Timing ◽

Pilot Injection ◽

Conventional Diesel Fuel

The aim of this work is to investigate the effect of mixing ratio and pilot injection on spray and combustion characteristics of biodiesel fuel and compared with those of diesel fuel in a direct injection common-rail diesel engine. In order to study the influence factors of biodiesel fuel on the spray and combustion characteristics, the experiments were conducted at various mixing ratios and injection conditions of the biodiesel and engine operating conditions. The macroscopic and microscopic characteristics such as injection rate, split injection effect, spray tip penetration, droplet diameter, and axial velocity distribution of biodiesel fuel were compared with the results of conventional diesel fuel by using spray visualization system composed of Ar-ion laser, ICCD camera and phase Doppler particle analyzer (PDPA) system. The combustion and exhaust emission characteristics of biodiesel fuel were studies using common-rail diesel engine with four cylinders. For the biodiesel blended fuel, it was revealed that higher injection pressure is needed to achieve the same injection rate at the higher mixing ratio. The spray tip penetration of biodiesel fuel was much the same with those of diesel. The atomization characteristics of biodiesel were inferior to conventional diesel fuel due to high viscosity and surface tension. The peak combustion pressures of both fuels were increased with advanced injection timing and the combustion pressure of biodiesel fuel is higher than that of diesel fuel. As the pilot injection timing is advanced to the TDC, the dissimilarities of both fuels combustion pressure are reduced. It can be also founded that the pilot injection can enhance the deteriorated spray and combustion characteristics of biodiesel fuel caused by physical fuel properties.

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Implementation of Common Rail Direct Injection System and Optimization of Fuel Injector Parameters in an Experimental Single-Cylinder Diesel Engine

Processes ◽

10.3390/pr8091122 ◽

2020 ◽

Vol 8 (9) ◽

pp. 1122

Author(s):

Yew Heng Teoh ◽

Heoy Geok How ◽

Ching Guan Peh ◽

Thanh Danh Le ◽

Huu Tho Nguyen

Keyword(s):

Diesel Engine ◽

Duty Cycle ◽

Direct Injection ◽

Common Rail ◽

Injection System ◽

Injection Timing ◽

Multiple Injection ◽

Fuel Injector ◽

Rail Pressure ◽

Open Time

The diesel engine is one of the solutions to slow down fossil fuel depletion due to its high efficiency. However, its high pollutant emission limits its usage in many fields. To improve its efficiency and emissions, a conventional mechanical fuel injection system (MFI) was be replaced with common rail direct injection (CRDI) system for the purpose of this study. In this way, injection parameters such as injection timing, injection pressure and multiple injection schemes can be tuned to enhance the engine performance. The rail pressure and engine speed response of the modified diesel engine was tested. It was found that by advancing the start of injection timing (SOI) timing or increasing the rail pressure, the brake torque generated can be increased. Multiple injection schemes can be implemented to reduce the peak heat release rate (HRR). Post injection was observed to increase the late combustion HRR. The maximum pressure rise rate (PRR) can be reduced by applying pilot injection. Further research was conducted on optimizing fuel injector parameters to improve the indicated mean effective pressure (IMEP) consistency and reduce injector power consumption. The consistency of IMEP was indicated by coefficient of variation (CoV) of IMEP. The injector parameters included open time, low time and duty cycle of injector signals. These parameters were optimized by carrying out response surface methodology. The optimized parameters were observed to be 230 µs for open time, 53µs for low time and 27.5% for duty cycle. The percentage of error of CoV of IMEP and injector power were found to be lower than 5% when the predicted results are compared with experimental results.

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