Optimization of Combustion Noise of Modern Diesel Engines for Passenger Cars

2007 ◽  
Author(s):  
Shanjin Wang ◽  
Christophe Chalu ◽  
Fabrice Gautier
Keyword(s):  
Diesel Engines ◽  
Combustion Noise ◽  
Passenger Cars

scholarly journals Ceramic Engine Components Under Commercial Production

1984 ◽  
Author(s):  
Yoshiteru Hamano ◽  
Masahiro Yamamoto
Keyword(s):  
Diesel Engines ◽  
Mass Production ◽  
Commercial Production ◽  
Cold Climate ◽  
Passenger Cars ◽  
Competitive Price ◽  
High Durability ◽  
Start Up ◽  
Ceramic Components ◽  
Engine Components

In the field of diesel engine components, ceramic glow plugs assisting quick start up of chamber diesel engines had been developed in September, 1981 and ceramic swirl chambers followed in commercialization in April, 1983. These ceramic components are currently under commercial production and are installed on passenger cars on the merket. Silicon nitride (Si3N4) is the material of these components, and a lot of mass-production technique has firmly established in order to achieve competitive price and high durability in comparison with the conventional metal components. Because of its excellent heating characteristics, ceramic glow plugs have eliminated the “waiting time” before the start-up of diesel engines. As the result, drivers can enjoy quick starting of engines as they can do with gasoline fueled vehicles. Ceramic swirl chambers could drastically reduce idling noise of diesel engines and remarkably improved starting performance in the cold climate operation.

A Signal Processing of In-Cylinder Pressure for the Resonant Frequency Prediction of Combustion Process in Diesel Engines

2018 ◽  
Author(s):  
Ximing Chen ◽  
Long Liu ◽  
Jiguang Zhang ◽  
Jingtao Du
Keyword(s):  
Signal Processing ◽  
Fourier Transform ◽  
Wavelet Transform ◽  
Resonant Frequency ◽  
Diesel Engines ◽  
Combustion Process ◽  
Combustion Noise ◽  
Injection Timing ◽  
Cylinder Pressure ◽  
Empirical Wavelet Transform

The combustion resonance is a focal point of the analysis of combustion and thermodynamic processes in diesel engines, such as detecting ‘knock’ and predicting combustion noise. Combustion resonant frequency is also significant for the estimation of in-cylinder bulk gas temperature and trapped mass. Normally, the resonant frequency information is contained in in-cylinder pressure signals. Therefore, the in-cylinder pressure signal processing is used for resonant frequency calculation. Conventional spectral analyses, such as FFT (Fast Fourier transform), are unsuitable for processing in-cylinder pressure signals because of its non-stationary characteristic. Other approaches to deal with non-stationary signals are Short-Time Fourier Transform (STFT) and Continue Wavelet Transform (CWT). However, the choice of size and shape of window for STFT and the selection of wavelet basis for CWT are totally empirical, which is the limit for precisely calculating the resonant frequency. In this study, an approach based on Empirical Wavelet Transform (EWT) and Hilbert Transform (HT) is proposed to process in-cylinder pressure signals and extract resonant frequencies. In order to decompose in-cylinder pressure spectrum precisely, the EWT are applied for separating the frequency band corresponding combustion resonance mode from other irrelevant modes adaptively. The signals containing combustion resonant mode is processed by HT, so that the instantaneous resonant frequency and amplitude can be extracted. Validation is performed by four in-cylinder pressure signals with different injection timing. And the effects of injection timing on resonant frequency are discussed.

scholarly journals Sensitivity of combustion noise and NOx and soot emissions to pilot injection in PCCI Diesel engines

2013 ◽  
Vol 104 ◽  
pp. 149-157 ◽  
Author(s):  
A.J. Torregrosa ◽  
A. Broatch ◽  
A. García ◽  
L.F. Mónico
Keyword(s):  
Diesel Engines ◽  
Combustion Noise ◽  
Pilot Injection ◽  
Soot Emissions

The Charging of Diesel Engines for Passenger Cars Using Turbochargers With Adjustable Turbine Guide Vanes

1982 ◽  
Author(s):  
M. Rautenberg ◽  
A. Mobarak ◽  
M. Malobabic
Keyword(s):  
Diesel Engine ◽  
Experimental Work ◽  
Diesel Engines ◽  
Passenger Cars ◽  
Guide Vanes ◽  
Low Speeds

Turbocharged passenger cars have been in use more than three decades. However, the behavior of the engine at low engine speeds is still unsatisfactory. Experimental work has been carried out on turbochargers aiming to improve the behavior of the engine at low speeds. For this purpose a turbine with adjustable guide vanes has been designed and tested. These experiments were done on a turbocharged 31 diesel engine from Daimler-Benz. Three different turbine nozzle blades have been designed and tested without using a waste gate. The results are compared with those of the Garrett-turbocharger T03 which was originally installed with the engine.

Preinjection—A Measure to Influence Exhaust Quality and Noise in Diesel Engines

1989 ◽  
Vol 111 (3) ◽  
pp. 445-450 ◽  
Author(s):  
H. Schulte ◽  
E. Scheid ◽  
F. Pischinger ◽  
U. Reuter
Keyword(s):  
Diesel Engines ◽  
High Speed ◽  
Combustion Noise ◽  
Injection System ◽  
Pilot Injection ◽  
Load Range ◽  
Injection Nozzle ◽  
Black Smoke ◽  
Injection Quantity ◽  
Main Injection

The combustion noise generated by DI diesel engines can be clearly reduced during both steady-state and transient operation in applying a pilot injection. After optimization, a slight increase in fuel consumption is found in the upper load range. The pilot injection also tends to reduce the NOx emissions. An increase in black smoke emissions is considered to be the main drawback with pilot injection. High-speed Schlieren photographs of injection and combustion phenomena within a pressurized chamber show that the higher black smoke emissions may be due to the combustion of the main injection quantity that occurs in a mixture that is insufficiently prepared and with nearly no delay due to the pilot injection. On the basis of these findings, it is concluded that a high degree of atomization and rapid vaporization of the main injection quantity must be accomplished. To achieve these goals better, a separate injection nozzle for the pilot quantity is preferred to an injection system with a single injection nozzle, providing both the pilot and the main quantity. Therefore, rather simple injection systems with a separate pilot injector can be developed that provide a constant pilot quantity and controlled pilot injection time over the entire engine map.

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