Refine Search

New Search

Results: 162,954

(searched for: publisher_group_id:8097)
Save to Scifeed
Page of 3,260
Articles per Page
by
Show export options
  Select all
Naoki Ohya, Kohei Hiyama, Kotaro Tanaka, Mitsuru Konno, , Takeshi Miki, Yutaka Tai
SAE International Journal of Fuels and Lubricants, Volume 10; https://doi.org/10.4271/2017-01-2386

Abstract:
Diesel engines have better fuel economy over comparable gasoline engines and are useful for the reduction of CO2 emissions. However, to meet stringent emission standards, the technology for reducing NOx and particulate matter (PM) in diesel engine exhaust needs to be improved. A conventional selective catalytic reduction (SCR) system consists of a diesel oxidation catalyst (DOC), diesel particulate filter (DPF), and urea-SCR catalyst. Recently, more stringent regulations have led to the development of SCR systems with a larger volume and increased the cost of such systems. In order to solve these problems, an SCR catalyst-coated DPF (SCR/DPF) is proposed. An SCR/DPF system has lower volume and cost compared to the conventional SCR system. The SCR/DPF catalyst has two functions: combustion of PM and reduction of NOx emissions. As PM is removed from the DPF at high temperatures (>650°C), the SCR/DPF system is exposed to higher temperatures as compared with those in the conventional SCR system. In this study, we investigated the NOx reduction performance and the properties of a hydrothermally aged SCR/DPF catalyst. Using these data, a model that can predict the NOx conversion of the hydrothermally aged SCR/DPF catalyst was constructed. A commercial copper-exchanged zeolite catalyst, Cu-ZSM-5, was used and aged in synthetic air with 10% water over the temperature range 650-750 °C. The effects of hydrothermal aging on the catalysts were investigated using a synthetic gas bench, and a detailed analysis of the structure of the hydrothermally aged catalyst was performed. Using the experimental data, we succeeded in constructing a hydrothermally aged SCR/DPF model for predicting the NOx conversion based on changes in the physicochemical characteristics of the catalysts with changes in the hydrothermal aging conditions. This work is the first step toward bridging the gap between a lab-simulated performance model and the global reactivity observed under real-world conditions.
Liu Xiaojun, Yu Jinpeng, Yang Xia, Wu Daoming, Jie Zhu
SAE International Journal of Alternative Powertrains, Volume 7; https://doi.org/10.4271/2017-01-2459

Xiangwang Li, Weimin Wang, Xiongcai Zou, Zhiming Zhang, Wenlong Zhang, Shemin Zhang, Tao Chen, Yuhuang Cao, Yuanda Chen
Published: 8 October 2017
SAE Technical Paper Series; https://doi.org/10.4271/2017-01-2432

Abstract:
In order to reduce emissions, size and manufacturing cost, integrated exhaust manifold become popular in gasoline engine, especially in three-cylinder engine. Moreover, due to shorter length, lighter weight, and less component connections, the exhaust manifold and hot end durability will improve apparently. In this work, an advanced cylinder head with integrated exhaust manifold is adopted in a three-cylinder turbo engine. Because of this integration characteristic, the gas retain in cylinder head longer and the temperature reach higher level than normal cylinder head, which will cause thermal fatigue failure more easily. To validate the exhaust manifold and hot end durability, series simulation and test validation work have been done. Firstly, overall steady state and transient temperature simulation was done for global model. For turbocharger, in order to simulate the outlet turbulent flow and 3d rotation, a code was compiled to define this 3d rotation. In this code, the inlet boundary was defined by turbine blade’s rotational velocity, direction and angle. Secondly, based on temperature prediction, thermal modal, high cycle fatigue (HCF) and thermal mechanical fatigue (TMF) analysis were done in sequence. According to HCF analysis, catalyst bracket fatigue factors fulfilled the require limit. According to TMF analysis, cylinder head life which contains the exhaust manifold fulfilled the life cycle target. Temperature and vibration test were done on rig test, good correlation is shown between test and simulation results. Finally, no crack failure was found inside the cylinder head and hot end after durability test, which also proved the TMF and HCF results indirectly.
Zhiming Zhang, Weimin Wang, Jiangtao Wang, Jiming Zhang, Yuanda Chen, Wenlong Zhang, Guofang Yang, Fugui Fan, Wenxiang Zhang, Fengqin Huang, et al.
Published: 8 October 2017
SAE Technical Paper Series; https://doi.org/10.4271/2017-01-2426

Yingmin Wang, Tao Cui, Fujun Zhang, Sufei Wang, Hongli Gao
Published: 8 October 2017
SAE Technical Paper Series; https://doi.org/10.4271/2017-01-2430

Abstract:
Considering the randomness and instability of the oil pressure in the lubrication system, a new approach for fault detection and diagnosis of diesel engine lubrication system based on support vector machine optimized by particle swarm optimization (PSO-SVM) model and centroid location algorithm has been proposed. Firstly, PSO algorithm is chosen to determine the optimum parameters of SVM, to avoid the blindness of choosing parameters. It can improve the prediction accuracy of the model. The results show that the classify accuracy of PSO-SVM is improved compared with SVM in which parameters are set according to experience. Then, the support vector machine classification interface is fitted to a curve, and the boundary conditions of fault diagnosis are obtained. Finally, diagnose algorithm is achieved through analyzing the centroid movement of features. According to Performance degradation data, degenerate trajectory model is established based on centroid location. And normal faults and performance degradation faults of diesel engine lubrication system are diagnosed. Results show that classification accuracy of the proposed PSO-SVM model achieved is 95.06% and 97.04% in two verify samples, it can meet the needs of fault diagnosis; and two typical faults and performance degradation fault of diesel engine can be diagnosed based on the proposed diagnosis method through simulation model based on AMESim.
, , Adam Weall, Brian Cooper
Published: 8 October 2017
SAE Technical Paper Series; https://doi.org/10.4271/2017-01-2429

Abstract:
Diesel engine designers often use swirl flaps to increase air motion in cylinder at low engine speeds, where lower piston velocities reduce natural in-cylinder swirl. Such in-cylinder motion reduces smoke and CO emissions by improved fuel-air mixing. However, swirl flaps, acting like a throttle on a gasoline engine, create an additional pressure drop in the inlet manifold and thereby increase pumping work and fuel consumption. In addition, by increasing the fuel-air mixing in cylinder the combustion duration is shortened and the combustion temperature is increased; this has the effect of increasing NOx emissions. Typically, EGR rates are correspondingly increased to mitigate this effect. Late inlet valve closure, which reduces an engine’s effective compression ratio, has been shown to provide an alternative method of reducing NOx emissions. Recently introduced technologies combine these two effects by retarding only the swirl port valve, increasing in-cylinder swirl while simultaneously reducing the effective compression ratio. In this paper the effects of using a swirl flap and offset cams are compared. Four different swirl flap positions (ranging from fully open to fully closed) were investigated using standard cams and valve timings. Results were compared with the engine’s operation when using two offset cams providing two different levels of retard on the swirl port—30 and 60 crank angle degrees (CAD) respectively. Engine emissions, fuel consumption, and combustion parameters were measured and compared in order to elucidate the effects of phased cam operation. The results show that the use of a cam retarding the opening of the swirl port can reduce NOx emissions at certain speed/load conditions without adversely affecting other emissions. In addition significantly retarding the swirl port closure can reduce FSN emissions to near zero with low NOx emissions, by a combination of high levels of swirl and a reduced effective compression ratio
Tanjin He, Hao-Ye Liu, Yingdi Wang, Boyuan Wang, Hui Liu, Zhi Wang
SAE International Journal of Fuels and Lubricants, Volume 10; https://doi.org/10.4271/2017-01-2336

Abstract:
Polyoxymethylene Dimethyl Ether (PODEn) is a promising green additive to diesel fuel, owing to the unique chemical structure (CH3O[CH2O]nCH3, n≥2) and high cetane number. Together with the general wide-distillation fuel (WDF), which has an attractive potential to reduce the cost of production of vehicle fuel, the oxygenated WDF with PODEn can help achieve a high efficiency and low emissions of soot, NOx, HC, and CO simultaneously. In this paper, the first detailed reaction mechanism (225 species, 1082 reactions) which can describe the ignition characteristics of PODE1 and PODE3 at low temperature was developed. To validate this mechanism, rapid compression machine (RCM) was used to conduct the quasi-homogeneous experiments to measure the ignition delay time at various effective temperatures (600 K - 1000 K) for four different PODE1/O2/N2/Ar mixture (ϕ=0.25, O2:Ar=1:5; ϕ=0.5, O2:Ar:N2 = 1:2.5:2.5; ϕ=1.0, O2:Ar:N2 = 1:2.5:2.5; ϕ=1.0, O2:Ar:N2 = 1:5:5) and two different effective pressures (10 bar, 19 bar). Homogeneous Charge Compression Ignition (HCCI) experiments fueled with PODEn (n=1-4) mixture, in which the mass fraction of PODE3 is about 88.9% were also conducted in a naturally aspirated single-cylinder HCCI research engine at 1600 r/min, 0.4 charge-mass equivalence ratio, and 42% exhaust gas recirculation (EGR) to take the real engine working condition into consideration. Good agreement was achieved in the comparison of the experimental data and the simulation results utilizing our newly developed mechanism for PODE1 and PODE3. Considering the fact that PODEn is more frequently used as a blending component in diesel engine, a reduced multi-component mechanism (354 species, 943 reactions) for oxygenated WDF with PODEn (covering surrogates like PODE3, n-heptane, iso-octane, etc.) was developed and then validated with Direct-Injection Compression Ignition (DICI) engine experiments fueled with oxygenated WDF (gasoline/diesel/PODEn mixture) at 1600 r/min, 0.8 MPa indicated mean effective pressure (IMEP), and 25% EGR. This surrogate model will contribute to the design of oxygenated WDF by blending PODEn, and to the prediction of the combustion and emission characteristics of engines using oxygenated WDF.
Fengqin Huang, Wenxin Cai, Zhiming Zhang, Wenlong Zhang, Laifeng Shi, Xin Li, Bernhard Kaltenegger, Daniele Suzzi, Werner Schrei, Karl Weihrauch
Published: 8 October 2017
SAE Technical Paper Series; https://doi.org/10.4271/2017-01-2433

Lei Zhou, Hongxing Zhang, Zhenfeng Zhao, Fujun Zhang
Published: 8 October 2017
SAE Technical Paper Series; https://doi.org/10.4271/2017-01-2408

Abstract:
The Opposed Piston Two-Stroke (OPTS) engine has many advantages on power density, fuel tolerance, fuel flexibility and package space. A type of self-balanced opposed-piston folded-crank train two-stroke engine for Unmanned Aerial Vehicle (UAV) was studied in this paper. AVL BOOST was used for the thermodynamic simulation. It was a quasi-steady, filling-and-emptying flow analysis -- no intake or exhaust dynamics were simulated. The results were validated against experimental data. The effects of high altitude environment on engine performance have been investigated. Moreover, the matching between the engine and turbocharger was designed and optimized for different altitude levels. The results indicated that, while the altitude is above 6000m, a multi-stage turbocharged engine system need to be considered and optimized for the UAV.
Shemin Zhang, Huaping Li, Tao Chen, Nan Jiang, Xinzhen Tan, Limei Deng, Qingsong Xia, Paul Kapus, Mingtang Ma, Wei Li, et al.
Published: 8 October 2017
SAE Technical Paper Series, Volume 1; https://doi.org/10.4271/2017-01-2424

Abstract:
In recent years, more attentions have been paid to stringent legislations on fuel consumption and emissions. Turbocharged downsized gasoline direct injection (DI) engines are playing an increasing important role in OEM’s powertrain strategies and engine product portfolio. Dongfeng Motor (DFM) has developed a new 1.0 liter 3-cylinder Turbocharged gasoline DI (TGDI) engine (hereinafter referred to as C10TD) to meet the requirements of China 4th stage fuel consumption regulations and the China 6 emission standards. In this paper, the concept of the C10TD engine is explained to meet the powerful performance (torque 190Nm/1500-4500rpm and power 95kW/5500rpm), excellent part-load BSFC and NVH targets to ensure the drivers could enjoy the powerful output in quiet and comfortable environment without concerns about the fuel cost and pollution. The combustion system with side-mounted 6-hole direct injector and 200bar injection pressure has been optimized by CFD simulation and optical engine investigation. To ensure performance output and transient responsiveness, an efficient and low inertia turbocharger was selected. Effective technical measures including friction reducing, thermal management, variable oil pump and Dual VVT were applied in order to achieve the good fuel economy. Special attentions have been paid to the engine structure design, mass balancing strategy and mounting system optimization to achieve excellent NVH performance which is at same level similar to a 4-cylinder TGDI gasoline engine. Benefited from the modular design concept, the engine size was minimized, which has the advantage for packaging, especially for hybrid vehicles. Through the development work, the engine performance and BSFC targets have been achieved and confirmed by engine and vehicle tests. This engine has been installed in one of the passenger cars (1205 to 1320kg) and 18% fuel consumption reduction has been achieved in the NEDC cycle compared to 1.6L NA engine while maintaining fun-to-drive and NVH performance
Hong Liu, Jiajia Jin, Hongyu Li, Kazuo Yamamori, Toyoharu Kaneko, Minoru Yamashita, Liping Zhang
SAE International Journal of Fuels and Lubricants, Volume 10; https://doi.org/10.4271/2017-01-2346

Nicolas Champagne, Nicolas Obrecht, Arup Gangopadhyay, Rob Zdrodowski, Z Liu
SAE International Journal of Fuels and Lubricants, Volume 10; https://doi.org/10.4271/2017-01-2343

Hyun-Soo Hong, Christopher Engel, Brian Filippini, Sona Slocum, Farrukh Qureshi, Tomoya Higuchi
SAE International Journal of Fuels and Lubricants, Volume 10; https://doi.org/10.4271/2017-01-2356

Ngsheng Zhang, Qilong Lu, Michael Kocsis, Ian Gilbert, Marc Megel, Xihao Liu, Jiaxin Gu, Qingyan Liu, Yanming He
Published: 8 October 2017
SAE Technical Paper Series, Volume 1; https://doi.org/10.4271/2017-01-2414

Eric Randolph, Raphael Gukelberger, Terrence Alger, Thomas Briggs, Christopher Chadwell, Antonio Bosquez Jr.
SAE International Journal of Fuels and Lubricants, Volume 10; https://doi.org/10.4271/2017-01-2285

Page of 3,260
Articles per Page
by
Show export options
  Select all
Back to Top Top