scholarly journals Simulation and Analysis of the Impact of Cylinder Deactivation on Fuel Saving and Emissions of a Medium-Speed High-Power Diesel Engine

2021 ◽  
Vol 11 (16) ◽  
pp. 7603 ◽  
Author(s):  
Ying Liu ◽  
Alexandr Kuznetsov ◽  
Bowen Sa
Keyword(s):  
Diesel Engine ◽  
Friction Model ◽  
Normal Operation ◽  
Lubricating Oil ◽  
Combustion Model ◽  
Connecting Rod ◽  
Cylinder Deactivation ◽  
Medium Speed ◽  
The Cost ◽  
The Impact

The potential benefit of cylinder deactivation (CDA) on power and emission performances has been numerically investigated on a locomotive 16-cylinder diesel engine. A 1D model combined with a predictive friction model and a 3D combustion model based and validated on experimental data have been developed to simulate engine working processes by deactivating half of the cylinders by cutting off the fuel supply and maintaining/cutting off valve motions. The results demonstrate that CDA with the valves closed decreases the BSFC by 11% at 450 rpm and by 14% at 556 rpm with a load of 1000 N∙m, due to increased indicated efficiency and reduced mechanical losses. After deactivating cylinders, frictional losses of piston rings increase in the active cylinders because of the raised gas pressure and the lubricating oil temperature decrease. Friction losses of the main bearings and big-end connecting rod bearings decrease due to the overall load drop. In comparison with the normal operation, CDA with the valves closed decreases the BSCO emission by 75.26% and the BSsoot emission by 62.9%. As the EGR rate is 30%, CDA with the valves closed effectively reduces the BSNOx emission to 4.2 g/(kW·h) at the cost of a 0.8% increase in the BSFC and without the rise in the BSCO emission.

EGR cylinder deactivation strategy to accelerate the warm-up and restart processes in a Diesel engine operating at cold conditions

2021 ◽  
pp. 146808742110395
Author(s):  
José Galindo ◽  
Vicente Dolz ◽  
Javier Monsalve-Serrano ◽  
Miguel Angel Bernal Maldonado ◽  
Laurent Odillard
Keyword(s):  
Steady State ◽  
Diesel Engine ◽  
Internal Combustion Engines ◽  
Cold Start ◽  
Pollutant Emissions ◽  
Oxidation Catalyst ◽  
Maximum Efficiency ◽  
Warm Up ◽  
Cylinder Deactivation ◽  
The Impact

The aftertreatment systems used in internal combustion engines need high temperatures for reaching its maximum efficiency. By this reason, during the engine cold start period or engine restart operation, excessive pollutant emissions levels are emitted to the atmosphere. This paper evaluates the impact of using a new cylinder deactivation strategy on a Euro 6 turbocharged diesel engine running under cold conditions (−7°C) with the aim of improving the engine warm-up process. This strategy is evaluated in two parts. First, an experimental study is performed at 20°C to analyze the effect of the cylinder deactivation strategy at steady-state and during an engine cold start at 1500 rpm and constant load. In particular, the pumping losses, pollutant emissions levels and engine thermal efficiency are analyzed. In the second part, the engine behavior is analyzed at steady-state and transient conditions under very low ambient temperatures (−7°C). In these conditions, the results show an increase of the exhaust temperatures of around 100°C, which allows to reduce the diesel oxidation catalyst light-off by 250 s besides of reducing the engine warm-up process in approximately 120 s. This allows to reduce the CO and HC emissions by 70% and 50%, respectively, at the end of the test.

Prediction of transient lubricating oil flows within the connecting-rod of a diesel engine

2011 ◽  
Vol 25 (1) ◽  
pp. 103-109 ◽  
Author(s):  
Shin-Hyoung Kang ◽  
Jeon-Gu Kim ◽  
Kyung-Nam Chung
Keyword(s):  
Diesel Engine ◽  
Lubricating Oil ◽  
Connecting Rod

scholarly journals Combustion Analysis of a Diesel Engine during Warm up at Different Coolant and Lubricating Oil Temperatures

Energies ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3931
Author(s):  
Faisal Lodi ◽  
Ali Zare ◽  
Priyanka Arora ◽  
Svetlana Stevanovic ◽  
Mohammad Jafari ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Ignition Delay ◽  
Peak Pressure ◽  
Cold Start ◽  
Lubricating Oil ◽  
Combustion Model ◽  
Injection Timing ◽  
Warm Up ◽  
Combustion Duration ◽  
Hot Start

A comprehensive analysis of combustion behaviour during cold, intermediately cold, warm and hot start stages of a diesel engine are presented. Experiments were conducted at 1500 rpm and 2000 rpm, and the discretisation of engine warm up into stages was facilitated by designing a custom drive cycle. Advanced injection timing, observed during the cold start period, led to longer ignition delay, shorter combustion duration, higher peak pressure and a higher peak apparent heat release rate (AHRR). The peak pressure was ~30% and 20% and the AHRR was ~2 to 5% and ±1% higher at 1500 rpm and 2000 rpm, respectively, during cold start, compared to the intermediate cold start. A retarded injection strategy during the intermediate cold start phase led to shorter ignition delay, longer combustion duration, lower peak pressure and lower peak AHRR. At 2000 rpm, an exceptional combustion behaviour led to a ~27% reduction in the AHRR at 25% load. Longer ignition delays and shorter combustion durations at 25% load were observed during the intermediately cold, warm and hot start segments. The mass fraction burned (MFB) was calculated using a single zone combustion model to analyse combustion parameters such as crank angle (CA) at 50% MFB, AHRR@CA50 and CA duration for 10–90% MFB.

scholarly journals Engine Performance and Emissions Analysis in a Cold, Intermediate and Hot Start Diesel Engine

2020 ◽  
Vol 10 (11) ◽  
pp. 3839 ◽  
Author(s):  
Faisal Lodi ◽  
Ali Zare ◽  
Priyanka Arora ◽  
Svetlana Stevanovic ◽  
Mohammad Jafari ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Cold Start ◽  
Lubricating Oil ◽  
Coolant Temperature ◽  
Effective Pressure ◽  
Warm Up ◽  
Hot Start ◽  
Depth Analysis ◽  
Performance And Emissions ◽  
The Impact

Presented in this paper is an in-depth analysis of the impact of engine start during various stages of engine warm up (cold, intermediate, and hot start stages) on the performance and emissions of a heavy-duty diesel engine. The experiments were performed at constant engine speeds of 1500 and 2000 rpm on a custom designed drive cycle. The intermediate start stage was found to be longer than the cold start stage. The oil warm up lagged the coolant warm up by approximately 10 °C. During the cold start stage, as the coolant temperature increased from ~25 to 60 °C, the brake specific fuel consumption (BSFC) decreased by approximately 2% to 10%. In the intermediate start stage, as the coolant temperature reached 70 °C and the injection retarded, the indicated mean effective pressure (IMEP) and the brake mean effective pressure (BMEP) decreased by approximately 2% to 3%, while the friction mean effective pressure (FMEP) decreased by approximately 60%. In this stage, the NOx emissions decreased by approximately 25% to 45%, while the HC emissions increased by approximately 12% to 18%. The normalised FMEP showed that higher energy losses at lower loads were most likely contributing to the heating of the lubricating oil.

Optimization of a Marine Medium-Speed Engine With Multi-Injector System by 1D Predictive Simulation

2021 ◽  
Author(s):  
Dai Liu ◽  
Peng Zhang ◽  
Long Liu ◽  
Qian Xia ◽  
Xiuzhen Ma
Keyword(s):  
Diesel Engine ◽  
Thermal Efficiency ◽  
Engine Performance ◽  
Nox Emission ◽  
Combustion Model ◽  
Injection Timing ◽  
Engine Model ◽  
Medium Speed ◽  
Injector System ◽  
Marine Medium

Abstract The thermal efficiency and emission of large bore marine medium-speed diesel engine are required to be improved under the stringent legislations. A multi-injector system has been proposed in order to improve the thermal efficiency and NOx emission instantaneously. However, application of the multi-injector system increased the complexity of parameter optimization and control. To develop proper control strategy of the novel multi-injector system, a 1D engine model of the original engine configurations was developed initially, including a predictive combustion model in commercial 1D simulation program (GT-Power). After calibrated by test results and literature data under various engine loads, the engine model was modified from a central single injector engine to a multi-injector engine. On the basis of a conventional direct-injection diesel engine, another two injectors were added to the cylinder as side injectors in the model. And the fundamental combustion characteristics and engine performance of the marine medium-speed diesel engine with multi-injector are investigated under various injection quantity ratio between the central injector and side injectors. The effects of injection timing and split injection are also studied by simulation. The result indicated that the effective thermal efficiency and NOx emission of the medium speed marine diesel engine are optimized instantaneously by changing the injection strategies of the central and side injectors. Finally, the preferred injection strategy is proposed by the 1D model.

scholarly journals BEHAVIOUR OF TRUCK’S COMPRESSOR’S CONNECTING RODS MADE OF ALUMINIUM ALLOY UNDER DIFFERENT MANUFACTURING CONDITIONS

Transport ◽  
2015 ◽  
Vol 31 (1) ◽  
pp. 41-46
Author(s):  
Rasa Kandrotaitė-Janutienė
Keyword(s):  
Impact Strength ◽  
Aluminium Alloy ◽  
Cost Reduction ◽  
Cyclic Loads ◽  
Connecting Rod ◽  
High Durability ◽  
Automotive Parts ◽  
Air Compressors ◽  
The Cost ◽  
The Impact

The main objective of this study was to explore quality increasing and cost reduction opportunities for a production of forged aluminium alloy 6082 connecting rods. These automotive parts are used for air compressors’ of the trucks. Connecting rods undergoes high cyclic loads during exploitation, therefore, the durability of this component is of a critical importance. The main factors characterizing high durability of the connecting rod are hardness and impact strength that may be achieved selecting the proper technology regimes. The main requirements for the aluminium alloy 6082 are hardness in the range of 90–120 HB and impact strength not less than 29.2 J/cm2. Furthermore, the main problem is a stability of testing results of randomly picked connecting rods as these parts are produced in big quantities for the export purposes. Our experiments and recommendations for the development of technology of connecting rods’ allowed maintaining the requirement in hardness, increasing the impact strength approximately twice and reducing the time needed for the production of one connecting rod as it let to save the cost of the part.

3-DIMENSIONAL NUMERICAL MODELING ON THE COMBUSTION AND EMISSION CHARACTERISTICS OF BIODIESEL IN DIESEL ENGINES

2014 ◽  
Vol 34 ◽  
pp. 1460371
Author(s):  
WENMING YANG ◽  
HUI AN ◽  
MAGHBOULI AMIN ◽  
JING LI
Keyword(s):  
Diesel Engine ◽  
Combustion Process ◽  
Nitrogen Monoxide ◽  
Combustion Model ◽  
Biodiesel Fuel ◽  
Formation Mechanisms ◽  
Fuel Injector ◽  
Dynamics Modeling ◽  
3 Dimensional ◽  
The Impact

A 3-dimensional computational fluid dynamics modeling is conducted on a direct injection diesel engine fueled by biodiesel using multi-dimensional software KIVA4 coupled with CHEMKIN. To accurately predict the oxidation of saturated and unsaturated agents of the biodiesel fuel, a multicomponent advanced combustion model consisting of 69 species and 204 reactions combined with detailed oxidation pathways of methyl decenoate (C11H22O2), methyl-9-decenoate (C11H20O2) and n-heptane (C7H16) is employed in this work. In order to better represent the real fuel properties, the detailed chemical and thermo-physical properties of biodiesel such as vapor pressure, latent heat of vaporization, liquid viscosity and surface tension were calculated and compiled into the KIVA4 fuel library. The nitrogen monoxide (NO) and carbon monoxide (CO) formation mechanisms were also embedded. After validating the numerical simulation model by comparing the in-cylinder pressure and heat release rate curves with experimental results, further studies have been carried out to investigate the effect of combustion chamber design on flow field, subsequently on the combustion process and performance of diesel engine fueled by biodiesel. Research has also been done to investigate the impact of fuel injector location on the performance and emissions formation of diesel engine.

An Assessment of the Relative Benefits of Miller Cycle and Turbocompounding on a Medium Speed Diesel Engine Using Second Law Analysis

2010 ◽  
Author(s):  
Thomas M. Lavertu ◽  
Roy J. Primus ◽  
Omowoleola C. Akinyemi
Keyword(s):  
Diesel Engine ◽  
Energy Recovery ◽  
Second Law ◽  
Miller Cycle ◽  
Medium Speed ◽  
Power Turbine ◽  
Second Law Analysis ◽  
Exhaust Energy ◽  
The Impact ◽  
Turbine Exhaust

The relative benefit of a power turbine as a means of exhaust energy recovery (i.e., turbocompounding) being used in conjunction with altered intake valve closure timing (Miller cycle) on a medium speed diesel engine has been investigated. An assessment of the impact of these different engine architectures on the various loss mechanisms has been performed using second law analysis. The Miller and turbocompounding cycle modification as well as the combination of the two features were studied and their relative benefits are compared and discussed. Results show the corresponding decrease in effective compression ratio achieved with Miller cycle leads to lower pre-turbine exhaust availability, which decreases the potential benefit of turbocompounding.

Lubrication analysis for the piston ring of a two-stroke marine diesel engine taking account of the oil supply

2019 ◽  
pp. 146808741987211 ◽  
Author(s):  
Tongyang Li ◽  
Xuan Ma ◽  
Xiqun Lu ◽  
Chuanjuan Wang ◽  
Bowen Jiao ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Piston Ring ◽  
Lubricating Oil ◽  
Design Parameters ◽  
Bench Test ◽  
Marine Diesel Engine ◽  
Oil Film ◽  
Oil Supply ◽  
Marine Diesel ◽  
The Impact

The piston ring is one of the most important parts of a two-stroke marine diesel engine. It is lubricated by a special mode in which the lubricating oil is directly injected into the liner’s inner surface. In this article, taking account of the oil supply, a piston ring lubrication model is developed based on oil mass conservation. The lubrication region of this piston ring–cylinder liner is divided into inlet, core lubrication, and outlet regions, with the oil supply being converted into an oil film. The impact of the width of the core lubrication region on squeezing of the oil is considered. To verify the model, friction force measurements are performed in a reciprocating bench test under fully flooded conditions, and the model is further validated by comparing the minimum oil film thickness with data from the literature. The model is applied to the top ring of a two-stroke marine diesel engine, and the impacts of the oil supply and its design parameters are analyzed.

scholarly journals Analysis of the Impact of Split Injection on Fuel Consumption and NOx Emissions of Marine Medium-Speed Diesel Engine

2020 ◽  
Vol 8 (10) ◽  
pp. 820
Author(s):  
Vladimir Pelić ◽  
Tomislav Mrakovčić ◽  
Radoslav Radonja ◽  
Marko Valčić
Keyword(s):  
Diesel Engine ◽  
Numerical Model ◽  
Fuel Consumption ◽  
Electric Propulsion ◽  
Nox Emissions ◽  
Split Injection ◽  
Propulsion Systems ◽  
Medium Speed ◽  
The Impact ◽  
Marine Medium

The medium-speed diesel engine in diesel-electric propulsion systems is increasingly used as the propulsion engine for liquefied natural gas (LNG) ships and passenger ships. The main advantage of such systems is high reliability, better maneuverability, greater ability to optimize and significant decreasing of the engine room volume. Marine propulsion systems are required to be as energy efficient as possible and to meet environmental protection standards. This paper analyzes the impact of split injection on fuel consumption and NOx emissions of marine medium-speed diesel engines. For the needs of the research, a zero-dimensional, two-zone numerical model of a diesel engine was developed. Model based on the extended Zeldovich mechanism was applied to predict NOx emissions. The validation of the numerical model was performed by comparing operating parameters of the basic engine with data from engine manufacturers and data from sea trials of a ship with diesel-electric propulsion. The applicability of the numerical model was confirmed by comparing the obtained values for pressure, temperature and fuel consumption. The operation of the engine that drives synchronous generator was simulated under stationary conditions for three operating points and nine injection schemes. The values obtained for fuel consumption and NOx emissions for different fuel injection schemes indicate the possibility of a significant reduction in NOx emissions but with a reduction in efficiency. The results showed that split injection with a smaller amount of pilot fuel injected and a smaller angle between the two injection allow a moderate reduction in NOx emissions without a significant reduction in efficiency. The application of split injection schemes that allow significant reductions in NOx emissions lead to a reduction in engine efficiency.

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