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.

Optimization of operating parameters of an off-road automotive diesel engine running at highway drive conditions using Response Surface Methodology

2020 ◽  
pp. 1-48 ◽  
Author(s):  
Vinod Babu Marri ◽  
K. Madhu Murthy ◽  
G. Amba Prasad Rao
Keyword(s):  
Response Surface Methodology ◽  
Fuel Injection ◽  
Injection Pressure ◽  
Operating Parameters ◽  
Injection Timing ◽  
Boost Pressure ◽  
Pilot Injection ◽  
Injection Quantity ◽  
Main Injection ◽  
Fuel Injection Pressure

Abstract The typical tradeoff between the two major emissions from compression ignition (CI) engines, smoke and oxides of nitrogen, is the unresolved challenge to the researchers. Techniques like engine downsizing, lowering intake oxygen concentration, multiple injections, use of retarded injection timings and higher injection pressures, etc. are widely employed for the alleviation of these harmful emissions. The influence of variation of fuel injection pressure (FIP), boost pressure, pilot injection timing (PIT), pilot injection quantity (PIQ) and main injection timing (MIT) are experimentally investigated in the present work. Mahindra mHawk four-cylinder diesel engine with provisions of a variable-geometry turbocharger (VGT), exhaust gas recirculation (EGR), and common-rail direct injection (CRDi) is chosen for the experimentation. Test runs are conducted at 1750 rpm and 80.3 N.m (4.6 bar bmep) corresponding to highway drive conditions, using 10 % EGR. Response surface methodology is employed for the design of experiments and to analyze the experimental data. Multi-objective response optimization is carried out to optimize engine-operating parameters that give desired performance and engine-out emissions. Confirmatory tests are conducted at design conditions to validate the results predicted by the model. This study reveals that the optimum performance and emission characteristics could be obtained using 120 kPa boost pressure; 61.1 MPa fuel injection pressure; 11.5 % pilot injection quantity with pilot injection at 332 °CA and main injection at 359 °CA.

Use of Taguchi Method to Optimize the Operating Parameters of a High-Pressure Injector Driving Circuit

2011 ◽  
Vol 130-134 ◽  
pp. 2795-2799 ◽  
Author(s):  
Wen Chang Tsai ◽  
Zong Hua Wu
Keyword(s):  
High Pressure ◽  
Taguchi Method ◽  
Power Supply ◽  
Fuel Injection ◽  
Supply Voltage ◽  
Operating Parameters ◽  
Control Parameters ◽  
Power Mosfet ◽  
Injection Quantity ◽  
Driving Circuit

This paper develops a superior injector driving circuit for a 500c.c. motorcycle GDI engine. The POWER MOSFET component is introduced in the design of the three-pulse injector driving circuit. Experiments for the designed electric driving circuit are investigated to verify its feasibility. The experiments of the H.P. injector driving circuit are conducted for the fuel injection quantity of the H.P. injector under 80~100 bar fuel pressure, 1200~2000 μs injection pulse duration and DC 55~65V power supply voltage. PWM control is introduced to the last pulse 3A holding current for fast cut-off response time of the H.P. injector. Next, Taguchi method was used to lead the design of experiments (DOE). The fuel injection quantities were measured in the various control parameters as engine speeds, power supply voltages, injector driving currents, and fuel supply pressures by the designed injector driving circuit. Effect of these control parameters of the high-pressure (H.P.) injector driving circuit on the fuel injection quantity are analyzed in the paper. Taguchi orthogonal array optimizes the operating parameters of the H.P. fuel injecting system. Results show that the three-pulse POWER MOSFET injector driving circuit is capable of operating stably and assure the accurate injection quantity of the H.P. injector.

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.

scholarly journals A feasibility study of implementation of oxy-fuel combustion on a practical diesel engine at the economical oxygen-fuel ratios by computer simulation

2020 ◽  
Vol 12 (12) ◽  
pp. 168781402098018
Author(s):  
Xiang Li ◽  
Zhijun Peng ◽  
Tahmina Ajmal ◽  
Abdel Aitouche ◽  
Raouf Mobasheri ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Water Injection ◽  
Fuel Combustion ◽  
Operating Parameters ◽  
Injection Timing ◽  
Zero Carbon ◽  
Oxygen Fuel ◽  
Charge Temperature ◽  
Engine Power

To help achieve zero carbon emissions from inland waterway vessels, this implementation of oxy-fuel combustion on a practical diesel engine at the economical oxygen-fuel ratios were systematically studied and analysed in this paper. A 1-D simulation was used to explore the effect of various operating parameters for recovering the engine power when the engine is modified to the oxy-fuel combustion from conventional air combustion. The brake power of oxy-fuel combustion is only 26.7 kW that has a noticeable decline compared with 40 kW of conventional air combustion with fixed consumption of fuel and oxygen. By optimising some valuable parameters, like fuel injection timing, intake charge temperature, intake components, engine compression ratio and water injection strategy, a benefit of 6.8 kW has been acquired in the engine power. Afterwards, a remarkable benefit was obtained with the increase of lambdaO2 from 1.0 to 1.5, finally obtaining the same engine power with the conventional air combustion. Above all, taking advantage of various operating parameters, it is expected to further improve the value of the implement of oxy-fuel combustion on diesel engines at the economical oxygen-fuel ratios.

An Improved Rate of Heat Release Model for Modern High-Speed Diesel Engines

2017 ◽  
Vol 139 (9) ◽  
Author(s):  
Peter G. Dowell ◽  
Sam Akehurst ◽  
Richard D. Burke
Keyword(s):  
Heat Release ◽  
Diesel Engines ◽  
Engine Speed ◽  
Fuel Injection ◽  
Maximum Pressure ◽  
Injection Model ◽  
Wall Impingement ◽  
Small Set ◽  
Rate Of Heat Release ◽  
Engine System

To meet the increasingly stringent emissions standards, diesel engines need to include more active technologies with their associated control systems. Hardware-in-the-loop (HiL) approaches are becoming popular where the engine system is represented as a real-time capable model to allow development of the controller hardware and software without the need for the real engine system. This paper focusses on the engine model required in such approaches. A number of semi-physical, zero-dimensional combustion modeling techniques are enhanced and combined into a complete model, these include—ignition delay, premixed and diffusion combustion and wall impingement. In addition, a fuel injection model was used to provide fuel injection rate from solenoid energizing signals. The model was parameterized using a small set of experimental data from an engine dynamometer test facility and validated against a complete data set covering the full engine speed and torque range. The model was shown to characterize the rate of heat release (RoHR) well over the engine speed and load range. Critically, the wall impingement model improved R2 value for maximum RoHR from 0.89 to 0.96. This was reflected in the model's ability to match both pilot and main combustion phasing, and peak heat release rates derived from measured data. The model predicted indicated mean effective pressure and maximum pressure with R2 values of 0.99 across the engine map. The worst prediction was for the angle of maximum pressure which had an R2 of 0.74. The results demonstrate the predictive ability of the model, with only a small set of empirical data for training—this is a key advantage over conventional methods. The fuel injection model yielded good results for predicted injection quantity (R2 = 0.99) and enabled the use of the RoHR model without the need for measured rate of injection.

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