scholarly journals A Predictive Real Time NOx Model for Conventional and Partially Premixed Diesel Combustion

2006 ◽  
Author(s):  
Magnus Andersson ◽  
Bengt Johansson ◽  
Anders Hultqvist ◽  
Christof Noehre
Keyword(s):  
Real Time ◽  
Diesel Combustion ◽  
Partially Premixed

scholarly journals A Real Time NOx Model for Conventional and Partially Premixed Diesel Combustion

2006 ◽  
Author(s):  
Magnus Andersson ◽  
Bengt Johansson ◽  
Anders Hultqvist ◽  
Christof Nöhre
Keyword(s):  
Real Time ◽  
Diesel Combustion ◽  
Partially Premixed

Real-time capable simulation of diesel combustion processes for HiL applications

2017 ◽  
Vol 19 (2) ◽  
pp. 214-229 ◽  
Author(s):  
Daniel Neumann ◽  
Christian Jörg ◽  
Nils Peschke ◽  
Joschka Schaub ◽  
Thorsten Schnorbus
Keyword(s):  
Heat Release ◽  
Real Time ◽  
Fuel Injection ◽  
Combustion Process ◽  
Boost Pressure ◽  
Diesel Combustion ◽  
Main Challenge ◽  
Combustion Properties ◽  
Input Variables ◽  
Improved Model

The complexity of the development processes for advanced diesel engines has significantly increased during the last decades. A further increase is to be expected, due to more restrictive emission legislations and new certification cycles. This trend leads to a higher time exposure at engine test benches, thus resulting in higher costs. To counter this problem, virtual engine development strategies are being increasingly used. To calibrate the complete powertrain and various driving situations, model in the loop and hardware in the loop concepts have become more important. The main effort in this context is the development of very accurate but also real-time capable engine models. Besides the correct modeling of ambient condition and driver behavior, the simulation of the combustion process is a major objective. The main challenge of modeling a diesel combustion process is the description of mixture formation, self-ignition and combustion as precisely as possible. For this purpose, this article introduces a novel combustion simulation approach that is capable of predicting various combustion properties of a diesel process. This includes the calculation of crank angle resolved combustion traces, such as heat release and other thermodynamic in-cylinder states. Furthermore, various combustion characteristics, such as combustion phasing, maximum gradients and engine-out temperature, are available as simulation output. All calculations are based on a physical zero-dimensional heat release model. The resulting reduction of the calibration effort and the improved model robustness are the major benefits in comparison to conventional data-driven combustion models. The calibration parameters directly refer to geometric and thermodynamic properties of a given engine configuration. Main input variables to the model are the fuel injection profile and air path–related states such as exhaust gas recirculation rate and boost pressure. Thus, multiple injection event strategies or novel air path control structures for future engine control concepts can be analyzed.

Real-Time Prediction of Incipient Lean Blowout in a Partially Premixed, Liquid-Fueled Gas Turbine Combustor

2007 ◽  
Author(s):  
Tongxun Yi ◽  
Ephraim J. Gutmark
Keyword(s):  
Real Time ◽  
Gas Turbine ◽  
Flame Structure ◽  
Rayleigh Distribution ◽  
Operating Conditions ◽  
Statistical Characteristics ◽  
Lean Blowout ◽  
Time Prediction ◽  
Two Indices ◽  
Partially Premixed

The present paper addresses real-time prediction of incipient lean blowout (LBO) in partially premixed, liquid-fueled gas turbine combustors. Near-LBO combustion is characterized by the “intensified” low-frequency combustion oscillations, typically below 30 Hz. Two indices, namely the normalized chemiluminescence RMS and the normalized cumulative duration of LBO precursor events, are recommended for LBO prediction. Both indices are associated with the statistical characteristics of the flame structure, which changes from the normal distribution to the Rayleigh distribution at the approach of LBO. Both indices change little within a large range of equivalence ratios and start to shoot up only when LBO is approached. To use the two indices for LBO prediction, one needs to perform a detailed a priori LBO mapping under simulated engine operating conditions. However, the mapping can be done without running the engines very close to LBO.

Partially Premixed Combustion Application for Diesel Power Improvement

2017 ◽  
Author(s):  
Michael Walker ◽  
Robert Kelso ◽  
Kevin Bowes ◽  
Len Hamilton ◽  
Dianne Luning Prak ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Jet Fuel ◽  
Premixed Combustion ◽  
Intake Manifold ◽  
Diesel Combustion ◽  
Unburned Hydrocarbon ◽  
Advanced Combustion ◽  
Partially Premixed Combustion ◽  
Partially Premixed ◽  
Start Of Combustion

A partially premixed combustion (PPC) approach was applied in a single cylinder diesel research engine in order to characterize engine power improvements. PPC is an alternative advanced combustion approach that generally results in lower engine-out soot and NOx emission, with a moderate penalty in engine-out unburned hydrocarbon (UHC) and carbon monoxide (CO) emissions. In this study PPC is accomplished with a minority fraction of jet fuel injected into the intake manifold, while the majority fraction of jet fuel is delivered directly to the combustion chamber near the start of combustion (SOC). Four compression ratios (CR) were studied. Exhaust emissions plus exhaust opacity and particulate measurements were performed during the experiments in addition to fast in-cylinder combustion metrics. It was seen that as CR increased the soot threshold equivalence ratio decreased for conventional diesel combustion, however this afforded an increased opportunity for higher levels of port injected fuel leading to power increases from 5 to 23% as CR increased from 14 to 21.5. PPC allowed for these power increases (defined by a threshold opacity level of 3%) due to smaller particles (and lower overall number of particles) in the exhaust that influence measured opacity less significantly than larger and more numerous conventional diesel combustion exhaust particulates. Carbon monoxide levels at the higher PPC driven power levels were only modestly higher, although NOx was generally lower due to the overall enriched operation.

Optical Investigations on Partially Premixed Diesel Combustion for Different Operating Parameters

2008 ◽  
Author(s):  
Marcus Schmid ◽  
Max Kaiser ◽  
Peter Koch ◽  
Michael Wensing ◽  
Alfred Leipertz
Keyword(s):  
Operating Parameters ◽  
Diesel Combustion ◽  
Partially Premixed
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