Evaluation of the residual gas tolerance of homogeneous combustion processes with high exhaust-gas recirculation rates

MTZ worldwide ◽  
2008 ◽  
Vol 69 (2) ◽  
pp. 40-46 ◽  
Author(s):  
Thomas Lauer ◽  
Bernhard Geringer
Keyword(s):  
Exhaust Gas Recirculation ◽  
Exhaust Gas ◽  
Homogeneous Combustion ◽  
Residual Gas ◽  
Combustion Processes ◽  
Gas Recirculation

scholarly journals Influence of Exhaust Gas Recirculation, and Injection Timing on the Combustion, Performance and Emission Characteristics of a Cylinder Head Porous Medium Engine

2015 ◽  
Vol 2015 ◽  
pp. 1-10
Author(s):  
Chidambaram Kannan ◽  
Thulasi Vijayakumar
Keyword(s):  
Combustion Chamber ◽  
Cylinder Head ◽  
Research Work ◽  
Exhaust Gas Recirculation ◽  
Injection Timing ◽  
Emission Characteristics ◽  
Exhaust Gas ◽  
Performance And Emission ◽  
Homogeneous Combustion ◽  
Gas Recirculation

Homogeneous combustion has the potential of achieving both near-zero emissions and low specific fuel consumption. However, the accomplishment of homogeneous combustion depends on the air flow structure inside the combustion chamber, fuel injection conditions, and turbulence as well as ignition conditions. Various methods and procedures are being adopted to establish the homogeneous combustion inside the engine cylinder. In this research work, a highly porous ceramic structure was introduced into the combustion chamber (underside of the cylinder head). The influence of operating parameters such as exhaust gas recirculation (EGR) and injection timing on the combustion, performance, and emission characteristics of such developed engine was investigated in this research work.

scholarly journals Model development and experimental validation of an exhaust brake supported dual loop exhaust gas recirculation on a medium duty Diesel engine

Mechanika ◽  
2020 ◽  
Vol 26 (6) ◽  
pp. 486-496
Author(s):  
Ádám NYERGES ◽  
Máté ZÖLDY
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Diesel Engines ◽  
Internal Combustion Engines ◽  
Exhaust Gas Recirculation ◽  
Exhaust Gas ◽  
State Variables ◽  
Commercial Vehicles ◽  
Combustion Processes ◽  
Gas Recirculation

Due to the new European emission norms internal combustion engines have to comply stricter rules. The new norms contain new requirements that were not included in previous regulations for example the decreased temperature of the cold start or the real driving emission part. The emission cycles for passenger vehicles are completely news, the stricter emission norms for commercial vehicles will follow them within a few years. Despite the increasing spread of alternative transmission systems in road transport Diesel engines are going to be remain in commercial vehicles in the next decades due to their good torque and fuel consumption performance. The emission of Diesel engines can be kept low by several way: by the modification of combustion processes, or by exhaust gas after treatment. To comply future regulations both of them seems to be necessary. By exhaust gas recirculation systems alternative Diesel combustion processes can be realized which can provide lower nitrogen-oxide emission and in several operation points also lower fuel consumption. Exhaust gas recirculation systems also can support the thermal management of a Diesel engine. To utilize the advantages of the recirculated exhaust gases a complex system is necessary to get a freedom in control possibilities: duel loop exhaust gas recirculated systems supplemented with supporter valves on the intake or on the exhaust side. In this paper a pressure and mass flow rate based control oriented engine model will be presented which contains high and low pressure exhaust gas recirculation systems and both of them are supported by exhaust brakes. The model considers four balance volumes and it has five state variables. The model is validated by an engine dyno measurements on a medium duty Diesel engine.

In-Cylinder CO2 Sampling Using Skip-Firing Method

2018 ◽  
Author(s):  
Matthew Duckhouse ◽  
Mark Peckham ◽  
Byron Mason ◽  
Edward Winward ◽  
Matthew Hammond
Keyword(s):  
Response Time ◽  
Gasoline Engine ◽  
Exhaust Gas Recirculation ◽  
Firing Cycle ◽  
Exhaust Gas ◽  
Engine Operation ◽  
Residual Gas Fraction ◽  
Residual Gas ◽  
Gas Recirculation ◽  
Firing Method

Skip-firing (or cylinder de-activation) was assessed as a method of sampling CO2 from directly in the cylinder at higher speeds than previously possible. CO2 was directly sampled from one cylinder of a 1-litre 3-cylinder gasoline engine to determine the residual gas fraction using a fast response CO/CO2 analyser. Acquisition of data for similar measurements is typically limited to engine speeds of below 1300 rpm to allow full resolution of the sample, through the analyser that has an 8 millisecond finite response time. In order to sample in-cylinder CO2 at higher engine speeds a skip-firing method is developed. By shutting off ignition intermittently during engine operation, the residual CO2 from the last firing cycle can be measured at significantly higher engine speeds. Comparison of residual gas fraction CO2 at low speeds for normal and skip-fire operation shows good correlation. This suggests that skip-firing is a suitable method for directly measuring internal exhaust gas recirculation up to at least 3000 rpm. The measurements obtained may provide a useful tool for validating internal exhaust gas recirculation models and could be used to calculate combustion air-fuel ratio from the CO and CO2 content of the burned gas. These are typically complicated parameters to predict due to the slow response time and sensitivity to hydrocarbons of wide-band oxygen sensors. A differing pattern of residual gas fraction change with increasing speed was seen between normal and skipfire operation.

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