Numerical and thermodynamic study on effects of high and low pressure exhaust gas recirculation on turbocharged marine low-speed engine

Wang, Dawei; Shi, Lei; Zhu, Sipeng; Liu, Bo; Qian, Yong; Deng, Kangyao

doi:10.1016/j.apenergy.2019.114346

Cited by 20 publications

(13 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This also explains a higher wear of the other piston rings with eEGR. The effects of low-and high-pressure eEGR on the performance and emission characteristics of a turbocharged marine diesel engine at a low speed have also been examined [50]. Figure 3 shows the effects of high pressure eEGR on NO x emissions at various engine loads and eEGR rates: a downward trend in NO x emission at partial loads when the eEGR rate increased at both high and low pressures.…”

Section: Effect Of Eegr On Diesel Engine Performance and Emission Cha...mentioning

confidence: 99%

A Review of the External and Internal Residual Exhaust Gas in the Internal Combustion Engine

Khoa

2022

Energies

View full text Add to dashboard Cite

Efficiency and emission reduction are the primary targets of internal combustion engine research due the large number of vehicles in operation and the impact of emissions-related pollution on human and ecosystem health. Harmful components of engine exhaust gases include nitrous oxides (NOx), carbon dioxide, hydrocarbons, and particulate matter. NOx emissions in particular are associated with significant health threats. The recirculation of exhaust gases can reduce NOx emissions and improve engine efficiency when combined with other advanced techniques. On the other hand, the residual exhaust gas also effects on the quality of lubricating engine oil and therefore causes an increase in engine piston ring wear. In this review paper, the effects of external and internal exhaust gas recirculation on the performance and emission characteristics of diesel, gasoline, and alternative fuel engines are summarized and discussed in detail. Because it is difficult to estimate the internal residual exhaust gas in the combustion engine by doing experiments. This review paper introduces control strategies and prediction methods for internal and external exhaust gas recirculation.

show abstract

Section: Effect Of Eegr On Diesel Engine Performance and Emission Cha...mentioning

confidence: 99%

A Review of the External and Internal Residual Exhaust Gas in the Internal Combustion Engine

Khoa

2022

Energies

View full text Add to dashboard Cite

show abstract

“…In addition, high-pressure (HP) and low-pressure (LP) EGR were studied by Wang. 23 HP EGR requires a wide high-efficiency area at a constant pressure ratio, while LP EGR needs a high-efficiency area as long as possible in its demand direction.…”

Section: Introductionmentioning

confidence: 99%

Effect of Exhaust Gas Recirculation Combined with Selective Catalytic Reduction on NO_x Emission Characteristics and Their Matching Optimization of a Heavy-Duty Diesel Engine

et al. 2022

View full text Add to dashboard Cite

Exhaust gas recirculation (EGR) and selective catalytic reduction (SCR) have become important technologies to reduce the NO x emission of heavy-duty diesel engines and meet the increasingly stringent emission regulations. This paper studied the effect of EGR combined with SCR on the NO x emission characteristics of a heavy-duty diesel engine based on the engine bench test. The results showed that the NO reduction rate of EGR-coupled SCR increased with the increase of engine load, and the effect was no longer significant when the NO reduction rate exceeded a certain limit under the same working conditions. EGR combined with SCR has little effect on NO 2 emission reduction, and the increase of engine speed can significantly improve the efficiency of the NO 2 reduction rate at 75 and 100% load. 25% opening of the EGR valve (OEV) and 50% OEV have very similar effects on the NO x reduction rate when the engine speed is at a low level. Compared with low engine speeds, increased OEV or ammonia NO x molar ratio (ANR) had a more obvious effect on the NO x reduction rate at high engine speeds. SCR combined with low valve-opening EGR had a more significant effect on the NO x reduction rate. The increase of OEV led to the increase of fuel consumption rate, but the effect on the fuel consumption rate decreased gradually with the increase of diesel engine speed. Meanwhile, this study optimized the matching relationship between OEV and ANR based on the data of the genetic algorithm, which provides a theoretical research method and application basis for diesel engine-matching of EGR and SCR.

show abstract

“…However, the LP-EGR system has higher requirements for exhaust gas filtration and cleaning, especially for marine two-stroke diesel engines that use heavy fuel oil. Moreover, the LP-EGR system is not as compact as the high-pressure EGR (HP-EGR) system, as low pressure leads to lower density of the EGR loop working medium [47]. The following two HP-EGR configurations are the most typical for marine two-stroke diesel engines [48]:…”

Section: Introductionmentioning

confidence: 99%

“…The detailed descriptions of these two configurations are provided in Lu et al [49], whereas their layouts are presented in Figure 1. The studies discussed in the preceding paragraphs [35][36][37][38]42,43,[45][46][47], as well as more recent studies [50][51][52], focused on the BL-EGR configuration for marine diesel engines equipped with one TC unit. However, studies on the BL-EGR engine configuration for larger size marine diesel engines equipped with two or more parallel TCs are not available in the pertinent literature.…”

mentioning

confidence: 99%

Comparative Assessment and Parametric Optimisation of Large Marine Two-Stroke Engines with Exhaust Gas Recirculation and Alternative Turbocharging Systems

Theotokatos

Zhang

et al. 2022

JMSE

View full text Add to dashboard Cite

Although the exhaust gas recirculation (EGR) technology has been proven effective to decrease the marine engine’s nitrogen oxides (NOx) emissions, it is associated with a considerable fuel consumption increase and challenges to the engine–turbocharger matching. This study aims to parametrically optimise the EGR and turbocharging system settings of a large marine two-stroke engine with the objective of obtaining the highest engine efficiency whilst ensuring compliance with the prevailing NOx emissions limits. Two typical configurations of the investigated engine (baseline and alternative) are modelled in the GT-SUITE software. Parametric simulations are performed with EGR rates up to 40% along with cylinder bypass rates up to 50%, and the simulation results are analysed to quantify the impact of the engine operation with EGR on the performance and NOx emissions parameters. For the baseline engine configuration, the EGR rate increase considerably deteriorates the brake specific fuel consumption (BSFC), which is attenuated by opening the cylinder bypass valve. The optimal combinations of the EGR and cylinder bypass rates for each operating point are identified for both configurations. Following the comparative assessment between the two engine configurations, recommendations for the engine operating modes are proposed, leading to BSFC improvement in the region of 0.7 to 2.9 g/kWh. This study provides insights for the operational settings optimisation of two-stroke engines equipped with EGR systems, contributing towards the reduction of the associated environmental carbon footprint.

show abstract

Numerical and thermodynamic study on effects of high and low pressure exhaust gas recirculation on turbocharged marine low-speed engine

Cited by 20 publications

References 47 publications

A Review of the External and Internal Residual Exhaust Gas in the Internal Combustion Engine

A Review of the External and Internal Residual Exhaust Gas in the Internal Combustion Engine

Effect of Exhaust Gas Recirculation Combined with Selective Catalytic Reduction on NO_x Emission Characteristics and Their Matching Optimization of a Heavy-Duty Diesel Engine

Comparative Assessment and Parametric Optimisation of Large Marine Two-Stroke Engines with Exhaust Gas Recirculation and Alternative Turbocharging Systems

Contact Info

Product

Resources

About

Numerical and thermodynamic study on effects of high and low pressure exhaust gas recirculation on turbocharged marine low-speed engine

Cited by 20 publications

References 47 publications

A Review of the External and Internal Residual Exhaust Gas in the Internal Combustion Engine

A Review of the External and Internal Residual Exhaust Gas in the Internal Combustion Engine

Effect of Exhaust Gas Recirculation Combined with Selective Catalytic Reduction on NOx Emission Characteristics and Their Matching Optimization of a Heavy-Duty Diesel Engine

Comparative Assessment and Parametric Optimisation of Large Marine Two-Stroke Engines with Exhaust Gas Recirculation and Alternative Turbocharging Systems

Contact Info

Product

Resources

About

Effect of Exhaust Gas Recirculation Combined with Selective Catalytic Reduction on NO_x Emission Characteristics and Their Matching Optimization of a Heavy-Duty Diesel Engine