Impact of Engine Operating Conditions on Particle Number and Size from a Small Displacement Automotive Diesel Engine

Currently the most promising solution for marine propulsion is the two-stroke low-speed diesel engine. Start of Injection (SOI) is of significant importance for these engines due to its effect on firing pressure and specific fuel consumption. Therefore these engines are usually equipped with Variable Injection Timing (VIT) systems for variation of SOI with load. Proper operation of these systems is essential for both safe engine operation and performance since they are also used to control peak firing pressure. However, it is rather difficult to evaluate the operation of VIT system and determine the required rack settings for a specific SOI angle without using experimental techniques, which are extremely expensive and time consuming. For this reason in the present work it is examined the use of on-board monitoring and diagnosis techniques to overcome this difficulty. The application is conducted on a commercial vessel equipped with a two-stroke engine from which cylinder pressure measurements were acquired. From the processing of measurements acquired at various operating conditions it is determined the relation between VIT rack position and start of injection angle. This is used to evaluate the VIT system condition and determine the required settings to achieve the desired SOI angle. After VIT system tuning, new measurements were acquired from the processing of which results were derived for various operating parameters, i.e. brake power, specific fuel consumption, heat release rate, start of combustion etc. From the comparative evaluation of results before and after VIT adjustment it is revealed an improvement of specific fuel consumption while firing pressure remains within limits. It is thus revealed that the proposed method has the potential to overcome the disadvantages of purely experimental trial and error methods and that its use can result to fuel saving with minimum effort and time. To evaluate the corresponding effect on NOx emissions, as required by Marpol Annex-VI regulation a theoretical investigation is conducted using a multi-zone combustion model. Shop-test and NOx-file data are used to evaluate its ability to predict engine performance and NOx emissions before conducting the investigation. Moreover, the results derived from the on-board cylinder pressure measurements, after VIT system tuning, are used to evaluate the model’s ability to predict the effect of SOI variation on engine performance. Then the simulation model is applied to estimate the impact of SOI advance on NOx emissions. As revealed NOx emissions remain within limits despite the SOI variation (increase).

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Influence of hydrocarbon species on its adsorption on a VSCR catalyst under simulated diesel engine operating conditions

Applied Catalysis B Environmental ◽

10.1016/j.apcatb.2017.05.077 ◽

2017 ◽

Vol 217 ◽

pp. 581-590 ◽

Cited By ~ 8

Author(s):

Yuanzhou Xi ◽

Nathan A. Ottinger ◽

Z. Gerald Liu

Keyword(s):

Diesel Engine ◽

Operating Conditions

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A Small Displacement DI Diesel Engine Concept for High Fuel Economy Vehicles

10.4271/972680 ◽

1997 ◽

Cited By ~ 7

Author(s):

David L. Boggs ◽

Richard C. Belaire ◽

Bernd Bartunek ◽

Manfred Dürnholz ◽

Hermann-Josef Ecker

Keyword(s):

Diesel Engine ◽

Fuel Economy ◽

Small Displacement ◽

Di Diesel Engine ◽

Engine Concept

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Simulation of a Single Cylinder Diesel Engine Under Cold Start Conditions Using Simulink

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.1290148 ◽

2000 ◽

Vol 123 (1) ◽

pp. 117-124 ◽

Cited By ~ 21

Author(s):

H.-Q. Liu ◽

N. G. Chalhoub ◽

N. Henein

Keyword(s):

Diesel Engine ◽

Direct Injection ◽

Cold Start ◽

Operating Conditions ◽

Combustion Model ◽

Nonlinear Dynamic Model ◽

Single Cylinder ◽

Engine Model ◽

Simulink Model ◽

Engine Components

A nonlinear dynamic model is developed in this study to simulate the overall performance of a naturally aspirated, single cylinder, four-stroke, direct injection diesel engine under cold start and fully warmed-up conditions. The model considers the filling and emptying processes of the cylinder, blowby, intake, and exhaust manifolds. A single zone combustion model is implemented and the heat transfer in the cylinder, intake, and exhaust manifolds are accounted for. Moreover, the derivations include the dynamics of the crank-slider mechanism and employ an empirical model to estimate the instantaneous frictional losses in different engine components. The formulation is coded in modular form whereby each module, which represents a single process in the engine, is introduced as a single block in an overall Simulink engine model. The numerical accuracy of the Simulink model is verified by comparing its results to those generated by integrating the engine formulation using IMSL stiff integration routines. The engine model is validated by the close match between the predicted and measured cylinder gas pressure and engine instantaneous speed under motoring, steady-state, and transient cold start operating conditions.

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