Effect of Exhaust Back Pressure on Performance and Emission Characteristics of Diesel Engine Equipped with Diesel Oxidation Catalyst and Exhaust Gas Recirculation

2018 ◽  
Vol 10 (3) ◽  
Author(s):  
Sangamesh Bhure
Keyword(s):  
Fuel Consumption ◽  
Exhaust System ◽  
Diesel Oxidation Catalyst ◽  
Back Pressure ◽  
Oxidation Catalyst ◽  
Exhaust Gas ◽  
Performance And Emission ◽  
Diesel Oxidation ◽  
Gas Recirculation ◽  
Exhaust Valves

Currently the emission norms are becoming more stringent, continuous modifications are taking place in existing I.C engines as well as in after treatment devices (ATDs). Exhaust Gas Recirculation (EGR) and Diesel Oxidation Catalyst (DOC) are the mandatory ATDs controlled electronically to optimize engine brake power, fuel consumption and emissions. The conversion efficiency of ATDs mainly depends on exhaust pressure, temperature, flow rate and fluid characteristics of exhaust gas. However, the installation of ATDs increases the exhaust back pressure in the exhaust system. The back pressure of engine also depends on the parameters like engine operating conditions, design of exhaust valves, valve lift time, exhaust gas dynamics and exhaust manifold design etc. In this paper the attempt is made to study the effect of back pressure on performance and emission of diesel engines equipped with EGR and DOC. Here we have not modified the intake and exhaust valves instead, we varied the back pressure of exhaust system using back pressure control valve (BPCV). BPCV is operated manually at three positions, they are 100%, 87.5% and 75% BPCV lifts. The readings are taken in different combinations of BPCV lifts and brake torque at 20, 40, 60, and 80 N-m. The results obtained shows variation of BPCV lift and brake torque effected on performance of engine, DOC and EGR operations as well as fuel consumption. The NOx is reduced by 15%; HC and CO are reduced significantly. However, there is an increase in brake specific fuel consumption (BSFC) and exhaust smoke.

scholarly journals ЗАСТОСУВАННЯ ГАЗОДИНАМІЧНОГО ОХОЛОДЖЕННЯ В СИСТЕМАХ РЕЦИРКУЛЯЦІЇ ВІДХІДНИХ ГАЗІВ СУДНОВИХ ДИЗЕЛІВ

2019 ◽  
pp. 81-86
Author(s):  
Дмитро Вікторович Коновалов
Keyword(s):  
Fuel Consumption ◽  
Exhaust Gas Recirculation ◽  
Back Pressure ◽  
Specific Fuel Consumption ◽  
Design Solution ◽  
Exhaust Gas ◽  
Engine Fuel ◽  
Gas Dynamics Equations ◽  
Exhaust Gases ◽  
Gas Recirculation

There are many ways and methods to reduce exhaust gases emissions on modern ships. One of the most effective ways to reduce NOx and SOx emissions is to use of exhaust gas recirculation (EGR technology). The EGR system disadvantage is an increase in back pressure through additional pressure losses in the scrubber and heat ex-changer, which entails an engine fuel efficiency deterioration. Creating a reliable and efficient heat exchanger for cooling recirculation gases is a complex task due to deposits and pollution emitted by these gases. In the pre-sent work, the jet apparatus effectiveness named aerothermopressor is analyzed in the scheme with exhaust gases recirculation of the ship low-speed two-stroke engine. Aerothermopressor is a two-phase jet for contact disperse cooling, in which by increasing the heat from the gas stream the gas pressure and cooling are increased. The calculation of the characteristics of the engine was carried out, both in nominal, and in operating modes and in all possible range of partial loads. The installation of the aerothermopressor before the scrubber is pro-posed, which allows reducing engine thermal load. Increasing the pressure in the aerothermopressor by 0.2-0.4 ∙ 105 Pa (6-12 %) allows reducing the back pressure in the gas exhaust system and thus reducing the load on the exhaust gas recirculation fan and when the engine load is higher than 75% in the cold zone, the fan is not need-ed, which additionally allows to reduce the specific fuel consumption. The parameters of the exhaust gases that are going to be recirculated and the processes of their gas-dynamic cooling in the aerothermopressor are based on the developed technique and program using the thermodynamic and gas dynamics equations. The proposed scheme-design solution allows at a high environmental friendliness of the existing exhaust gas recirculation sys-tem to provide a certain reduction in specific fuel consumption. It was determined that the engine specific fuel consumption has been decreasing when the aerothermopressor is used to Dge = 2.5-3.0 g/(kW·h) (1.5-1.7%).

A Parametric Study of Diesel Oxidation Catalyst Performance on CO Reduction in Diesel Dual Fuel Engine Exhaust

2015 ◽  
Vol 656-657 ◽  
pp. 538-543 ◽  
Author(s):  
Sirichai Jirawongnuson ◽  
Worathep Wachirapan ◽  
Tul Suthiprasert ◽  
Ekathai Wirojsakunchai
Keyword(s):  
Diesel Oxidation Catalyst ◽  
Oxidation Catalyst ◽  
Dual Fuel ◽  
Exhaust Gas ◽  
Gas Temperature ◽  
Engine Exhaust ◽  
Gas System ◽  
Diesel Oxidation ◽  
Co Reduction ◽  
Exhaust Gas Temperature

In this research study, a synthetic exhaust gas system is employed to simulate various exhaust conditions similar to those from conventional diesel and Dual Fuel-Premixed Charge Compression Ignition (DF-PCCI) combustion. OEM DOC is tested to compare the effectiveness of reducing CO from both exhaust characteristics. Variations of the temperature and the concentration of CO, THC, and O2 are done to investigate DOC performance on CO reductions according to Design of Experiment (DOE) concept. The results showed that in DF-PCCI exhaust conditions, DOC requires higher exhaust gas temperature as well as O2 concentration to reduce CO emissions.

Performance and Emission Characteristics of a CRDe SUV Fueled With Neat Biodiesel (B-100) From Jatropha, Pongamea Source and Diesel Fuel

2009 ◽  
Author(s):  
Murali Manickam ◽  
Mithun Kadambamattam ◽  
Gajarlawar Nilesh ◽  
Ghodke Pundlik ◽  
Mathew Abraham
Keyword(s):  
Diesel Engine ◽  
Methyl Ester ◽  
Diesel Oxidation Catalyst ◽  
Raw Material ◽  
Oxidation Catalyst ◽  
Injection Timing ◽  
Exhaust Gas ◽  
Gas Temperature ◽  
Performance And Emission ◽  
Exhaust Gas Emission

Present investigation addresses the use of neat, indigenous biodiesel (B100) in a sports utility vehicle (SUV) with second generation common rail technology. Current research determines the effect of biodiesel (B100) on performance & emission of modern diesel engine, equipped with diesel oxidation catalyst. Biodiesel used in this study were Pongamea Methyl Ester (PME) & Jatropha Methyl Ester (JME) derived from vegetable oil. Fuel related aspects for these two raw material and its effects on engine characteristics were discussed. Both engine & vehicle level tests had been carried out with the aim of obtaining performance characteristics such as brake specific fuel consumption, brake thermal efficiency, brake power, exhaust gas temperature, & emissions such as CO, THC, NOx, smoke opacity to evaluate and compute the behaviors of diesel engine running on PME & JME. Comparative vehicle performance like drivability, gradeability and noise was also measured between biodiesel and diesel. Experimental results revealed that significant reduction in power was observed through out the operating range in both JME & PME, because of its lower heating value. Between this two biodiesel, there was a visible difference in power drop. Engine exhaust gas emission like Hydrocarbon (HC), Carbon monoxide (CO), & Smoke emission reduce significantly, when engine runs with biodiesel (JME & PME) meanwhile using of B100 causes increase in Nitrogen oxide (NOx) emission. Particulate matter was significantly lower than those of a vehicle running on fossil diesel. However loss in power, when using biodiesel has been regained by increasing the fuelling & optimizing the combustion parameters like rail pressure, injection timing & duration. Based on the study it is observed that B100 can be used as fuel in diesel engine without any hardware modification, but only by remapping the CRDe system.

Applicable Diesel Oxidation Catalyst for Multi-Diesel Exhaust System

2014 ◽  
Vol 7 (2) ◽  
pp. 496-502 ◽  
Author(s):  
Yosuke Goto ◽  
Naohiro Kato ◽  
Shota Kawashima ◽  
Yoshiyuki Hayashi ◽  
Hideki Goto ◽  
...  
Keyword(s):  
Diesel Exhaust ◽  
Exhaust System ◽  
Diesel Oxidation Catalyst ◽  
Oxidation Catalyst ◽  
Diesel Oxidation

A Physically-Based, Control-Oriented Diesel Oxidation Catalyst (DOC) Model for the Applications of NO/NO2 Ratio Estimation Using a NOx Sensor

2010 ◽  
Author(s):  
Ming-Feng Hsieh ◽  
Junmin Wang
Keyword(s):  
Diesel Engine ◽  
Diesel Oxidation Catalyst ◽  
Oxidation Catalyst ◽  
Particulate Filter ◽  
Exhaust Gas ◽  
Ratio Estimation ◽  
Engine Exhaust ◽  
Diesel Oxidation ◽  
Physically Based ◽  
Aftertreatment Systems

NO and NO2 are generally considered together as NOx in engine emissions. Since NO2/NOx ratio is small in diesel engine exhaust gas, very often, existence of NO2 is ignored in studies/applications. However, current diesel aftertreatment systems generally include diesel oxidation catalysts (DOCs) at upstream of other catalysts such as diesel particulate filter (DPF) and selective catalytic reduction (SCR). DOC can significantly increase the NO2 fraction in the exhaust NOx. Because NO2 and NO have completely different reaction characters within catalysts, e.g. NO2 can assist DPF regeneration while NO cannot, and SCR De-NOx rate can be increased with higher NO2/NOx ratio (no more than 0.5), considerations of NO2 in aftertreatment systems are becoming necessary. Nevertheless, current onboard NOx sensors cannot differentiate NO and NO2 from NOx. This induces an interest in the method of estimating the concentrations of NO and NO2 in the exhaust gas by available measurements. In this paper, a physically-based, DOC control-oriented model which considers the NO and NO2 related dynamics and an engine exhaust NO/NO2 prediction method were proposed for the purposes of NO/NO2 ratio estimation in diesel engine aftertreatment systems, and the developed model was validated with experimental data.

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