Phasing cylinder pressure to crank angle in a direct injection diesel engine, by simulation of compression curve and elaboration of measured pressure data (EN)

Kouremenos, DA (EN)

Rakopoulos, CD (EN)

Kotsos, CG (EN)

When measurements of indicator diagrams are made in an internal combustion engine, the serious problem arises of accurate phasing of pressure data to crank position. This work presents a novel thermodynamic method for such a phasing. A measuring assembly consisting of a piezoelectric transducer, a charge amplifier and a fast data acquisition board installed on a compatible PC computer, is used to obtain the indicator diagrams (i.e. pairs of pressure-time), dispensing thus with the use of a signal from the flywheel TDC marker. An advanced simulation thermodynamic model for the corresponding compression curve (i.e. before fuel injection) is proposed, which includes a detailed zero dimensional energy cascade turbulence submodel for predicting the heat transfer rate between cylinder gas and walls, a blowby rate submodel containing flow calculations in the piston ring pack assembly passages under rings motion conditions, and properties-relations pertaining to real gas (air) behaviour. The measured pressure data are corrected for drift and their exact period (from cycle to cycle) is determined. The theoretical compression curve is shifted (in time) to ""coincide"" to the compression part (before fuel injection) of the first measured cycle, so that its TDC is determined. The coincidence of the two compression curves is continuously (iteratively) improved by using a double iteration procedure, i.e. by firstly shifting the curves in time and secondly by varying the model's parameters and calibration constants. After this step, the phasing of pressure data to crank angle of the following cycles can be easily determined, since the corresponding time periods are already accurately calculated. The method is applied with success, under various speed and load conditions, for a fully instrumented single cylinder, LISTER LV1, direct injection, naturally aspirated, Diesel engine installation at the authors' laboratory. © 1991 VDI Verlag GmbH. (EN)

journalArticle (EN)

Engineering, Multidisciplinary (EN)

Pressure diagrams (EN)

Combustion (EN)

Thermodynamic Model (EN)

Data Acquisition (EN)

Diesel Engine (EN)

Engineering, Mechanical (EN)

Thermodynamics (EN)

Direct Injection (EN)

Internal Combustion Engine (EN)

Direct fuel injection (EN)

Diesel engines (EN)

Internal combustion engines (EN)

Top dead center (EN)

Heat Transfer (EN)

Fuel injection (EN)

National Technical University of Athens

Digital Library of National Technical University of Athens | Dspace@NTUA

Κεντρική Βιβλιοθήκη Ε.Μ.Π.

Ιδρυματικό Αποθετήριο

Δημοσιεύσεις μελών Δ.Ε.Π. σε περιοδικά

Forschung im Ingenieurwesen (EN)

English

1991 (EN)

http://hdl.handle.net/123456789/10520

57 (EN)

10.1007/BF02561172 (EN)

3 (EN)

ISI:A1991FN44300004 (EN)

0015-7899 (EN)

95 (EN)

87 (EN)

Springer-Verlag (EN)