SAE transactions最新文献

{"title":"Calculation accuracy of pulsating flow through the turbine of Si-engine turbochargers - Part 2 Measurements, simulation correlations and conclusions","authors":"Fredrik Westin, Hans-Erik Ångström","doi":"10.4271/2005-01-3812","DOIUrl":"https://doi.org/10.4271/2005-01-3812","url":null,"abstract":"This paper is a continuation of SAE-Paper 2005-01-0222 presented at the 2005 SAE World Congress, denoted Part 1 in this text. In Part 1 three turbines were selected from calculations and three manifolds with different geometries were designed. This paper, Part 2, covers the results from engine-simulations and measurements on these nine different combinations of turbines and manifolds. It was shown that the possibility of maintaining isentropic power was the most important property, overshadowing any differences in turbine efficiency. The isentropic power was inversely dependent on both manifold volume and turbine throat area. The GT-Power models of all nine setups were calibrated against the measured data. The need for efficiency and massflow multipliers is described. The efficiency multiplier depended on mass flow through the turbine, with a distinct minimum value (0.7-0.8) around 0.03 kg/s and higher around that. The efficiency multiplier could not be shown to depend on pulsation amplitude of the turbine inlet flow. The mass flow multiplier was almost linear with engine speed. The on-engine turbine efficiency was calculated from a combination of measured and simulated data. Different approaches for this calculation were tested, among which also mass storage was included. The chosen method used equal massflow in and out from the turbine at every instant and a floating average over 30 CAD. To enable explanation of the different behaviors on the engine, detailed measurements were conducted on the three turbines in a steady-state turbine flow rig. These measurements were used to calibrate separate turbine simulation models in the software Rital, which were used to describe the internal flow of the turbines. The three methods of estimating the on-engine turbine efficiency were compared. GT-Power and Rital showed similar trends for the efficiency, but the on-engine measured efficiency gave lower values for the first, most energetic, part of the exhaust pulse. Furthermore, the three manifold types were analyzed and the benefits from each of them sorted out.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"44 1","pages":"1662-1684"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86678783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Investigations of Different Parameters Affecting the Performance of a CNG - Diesel Dual Fuel Engine","authors":"I. NafisAhmad, M. Babu, A. Ramesh","doi":"10.4271/2005-01-3767","DOIUrl":"https://doi.org/10.4271/2005-01-3767","url":null,"abstract":"In a dual fuel engine a primary fuel that is generally a gas is mixed with air, compressed and ignited by a small pilot- spray of diesel as in a diesel engine. Dual fuel engines generally suffer from the problem of lower brake power and lower peak engine cylinder pressure due to lower volumetric efficiency, although an improvement in brake specific energy consumption is observed compared to pure diesel mode. Results indicate that with an increase in percentage of CNG substitution the brake power decreases. The exhaust gas temperature and peak cylinder pressure also decrease. The rate of pressure rise is higher at lower engine speeds (1100, 1400 rev/min), although at 1700 and 2000 rev/min it is lower. The delay period throughout the engine speed shows an increasing trend. The coefficient of variation is also higher throughout the engine speeds and shows an increasing trend. The brake specific energy consumption is lower at 1100, 1400 and 1700 rev/min and at 2000 rev/min it is higher. The model, which illustrates the simulation of the power cycle of a pre-chamber diesel engine consisting of compression, combustion and expansion processes predicts brake-power, delay period, brake specific energy consumption and maximum cylinder gas pressure for various percentage of CNG substitution. The above model was validated using available experimental results.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"61 1","pages":"1620-1629"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80879584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing the Geometry of a Half-Toroidal CVT","authors":"S. Akbarzadeh, H. Zohoor","doi":"10.4271/2005-01-3780","DOIUrl":"https://doi.org/10.4271/2005-01-3780","url":null,"abstract":"In this research a model is developed which calculates the torque transmission efficiency of a half-toroidal CVT as a function of variator geometry, gear ratio and input torque. The different criteria which are considered to be important in a half toroidal CVT performance are torque transmission efficiency, variator weight, roller fatigue life and bearing torque loss. Variation of geometrical characteristics such as roller curvature, number of power rollers, aspect ratio and half cone angle affect these criteria in different ways. Therefore, in order to find the optimal quantity for each geometrical parameter an optimization problem should be developed. The objective function of this optimization problem consists of inverse of torque transmission efficiency, system weight, roller fatigue life and torque loss. After choosing the appropriate weight factors, the Genetic Algorithm method is employed to minimize the objective function. It is believed that the geometry proposed in this paper can increase the efficiency of the variator to 94.4 percent.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"23 1","pages":"1476-1481"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84828816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cetane Number and Engine Speed Effects on Diesel HCCI Performance and Emissions","authors":"J. Szybist, B. Bunting","doi":"10.4271/2005-01-3723","DOIUrl":"https://doi.org/10.4271/2005-01-3723","url":null,"abstract":"The effects of cetane number (CN) on homogeneous charge compression ignition (HCCI) performance and emissions were investigated in a single cylinder engine using intake air temperature for control. Blends of the diesel secondary reference fuels for cetane rating were used to obtain a CN range from 19 to 76. Sweeps of intake air temperature at a constant fueling were performed. Low CN fuels needed to be operated at higher intake temperatures than high CN fuels to achieve ignition. As the intake air temperature was reduced for a given fuel, the combustion phasing was retarded, and each fuel passed through a phasing point of maximum indicated mean effective pressure (IMEP). Early combustion phasing was required for the high CN fuels to prevent misfire, whereas the maximum IMEP for the lowest CN fuel occurred at a phasing 10 crank angle degrees (CAD) later. The high CN fuels exhibited a strong low temperature heat release (LTHR) event, accounting for more than 15% of the total heat release in some instances, while no LTHR was detected for fuels with CN ≤ 34. All of the fuels had comparable NOx emissions and pressure rise rates at their respective maximum IMEP timing, with NOx emissions below 6 ppm at 3.5 bar IMEP. At advanced combustion phasing, low CN fuels had significantly higher pressure rise rates and higher NOx emissions than the high CN fuels. At retarded phasing, the CO emissions for the high CN fuels were excessive, with a CO:UHC ratio of up to 8, while these remained <1 for low CN fuels. These results suggest that the products of LTHR, which are high in CO, are more sensitive to the quenching effects of cylinder expansion. Thus high CN fuels, which exhibit significant LTHR, require early combustion phasing, whereas low CN fuels can be retarded to later combustion phasing. Increasing engine speed had the effect of reducing the total LTHR. Further investigation showed that the LTHR rate is constant on a millisecond basis, so the effect of higher engine speed is to reduce the time allowed for the reaction without changing the rate of reaction.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"7 5","pages":"1334-1346"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91428056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soot Formation in Diesel Combustion under High-EGR Conditions","authors":"C. Idicheria, L. Pickett","doi":"10.4271/2005-01-3834","DOIUrl":"https://doi.org/10.4271/2005-01-3834","url":null,"abstract":"Experiments were conducted in an optically accessible constant-volume combustion vessel to investigate soot formation at diesel combustion conditions - in a high exhaust-gas recirculation (EGR) environment. The ambient oxygen concentration was decreased systematically from 21% to 8% to simulate a wide range of EGR conditions. Quantitative measurements of in-situ soot in quasi-steady n-heptane and No.2 diesel fuel jets were made by using laser extinction and planar laser-induced incandescence (PLII) measurements. Flame lift-off length measurements were also made in support of the soot measurements. At constant ambient temperature, results show that the equivalence ratio estimated at the lift-off length does not vary with the use of EGR, implying an equal amount of fuel-air mixing prior to combustion. Soot measurements show that the soot volume fraction decreases with increasing EGR. The regions of soot formation are effectively 'stretched out' to longer axial and radial distances from the injector with increasing EGR, according to the dilution in ambient oxygen. However, the axial soot distribution and location of maximum soot collapses if plotted in terms of a 'flame coordinate', where the relative fuel-oxygen mixture is equivalent. The total soot in the jet cross-section at the maximum axial soot location initially increases and then decreasesmore » to zero as the oxygen concentration decreases from 21% to 8%. The trend is caused by competition between soot formation rates and increasing residence time. Soot formation rates decrease with decreasing oxygen concentration because of the lower combustion temperatures. At the same time, the residence time for soot formation increases, allowing more time for accumulation of soot. Increasing the ambient temperature above nominal diesel engine conditions leads to a rapid increase in soot for high-EGR conditions when compared to conditions with no EGR. This result emphasizes the importance of EGR cooling and its beneficial effect on mitigating soot formation. The effect of EGR is consistent for different fuels but soot levels depend on the sooting propensity of the fuel. Specifically, No.2 diesel fuel produces soot levels more than ten times higher than those of n-heptane.« less","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"03 1","pages":"1559-1574"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85962606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"R&D and Analysis of Energy Consumption Improvement Factor for Advanced Clean Energy HEVs","authors":"K. Morita, K. Shimamura, G. Sugiyama, M. Hori, Y. Itai, S. Sekiyama, A. Motooka, M. Sasaki, Koichiro Suenaga","doi":"10.4271/2005-01-3828","DOIUrl":"https://doi.org/10.4271/2005-01-3828","url":null,"abstract":"Ultra-low energy consumption and ultra-low emission vehicle technologies have been developed by combining petroleum-alternative clean energy with a hybrid electric vehicle (HEV) system. Their component technologies cover a wide range of vehicle types, such as passenger cars, delivery trucks, and city buses, adsorbed natural gas (ANG), compressed natural gas (CNG), and dimethyl ether (DME) as fuels, series (S-HEV) and series/parallel (SP-HEV) for hybrid types, and as energy storage systems (ESSs), flywheel batteries (FWBs), capacitors, and lithium-ion (Li-ion) batteries. Evaluation tests confirmed that the energy consumption of the developed vehicles is 1/2 of that of conventional diesel vehicles, and the exhaust emission levels are comparable to Japan's ultra-low emission vehicle (J-ULEV) level. In the analysis of energy consumption improvement factors, it was found that a heavy-duty (HD)-HEV benefits from the effect of regenerative braking to a greater extent than a light-duty (LD)-HEV.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"8 1","pages":"1691-1704"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88912711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of Heavy Loads on Light Duty Vehicle Axle Operating Temperature","authors":"B. M. O'connor, Chris Schenkenberger","doi":"10.4271/2005-01-3893","DOIUrl":"https://doi.org/10.4271/2005-01-3893","url":null,"abstract":"With the continued growth of the sport utility vehicle (SUV) market in North America in recent years more emphasis has been placed on fluid performance in these vehicles. In addition to fuel economy the key performance area sought by original equipment manufacturers (OEMs) in general has been temperature reduction in the axle. This is being driven by warranty claims that show that one of the causes of axle failure in these type vehicles is related to overheating. The overheating is, in turn, caused by high load situations, e.g., pulling a large trailer at or near the maximum rated load limit for the vehicle, especially when the vehicle or its main subcomponents are relatively new. The excessive temperature generally leads to premature failure of seals, bearings and gears. The choice of lubricant can have a significant effect on the peak and stabilized operating temperature under these extreme conditions. Several laboratory methods evolved with time and experience to assess lubricant performance. One laboratory method was created to reproduce a scenario leading to the stated warranty issues encountered by some equipment manufacturers today. This involved using a new axle and subjecting it to a simulated severe road condition after a short break-in period and measuring the peak temperature as a function of fluid type. This was later validated with actual vehicle evaluations conducted in a desert region of the USA in high ambient temperature conditions. Good correlation was observed between the laboratory and vehicle methods. Further refinement of the laboratory method now is in progress based on vehicle data obtained during these evaluations. Both methods showed that fluid choice can have a significant effect on peak and stabilized temperatures.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"59 1","pages":"1827-1832"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86765554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"2-Color Thermometry Experiments and High-Speed Imaging of Multi-Mode Diesel Engine Combustion","authors":"Satbir Singh, R. Reitz, M. Musculus","doi":"10.4271/2005-01-3842","DOIUrl":"https://doi.org/10.4271/2005-01-3842","url":null,"abstract":"Although in-cylinder optical diagnostics have provided significant understanding of conventional diesel combustion, most alternative combustion strategies have not yet been explored to the same extent. In an effort to build the knowledge base for alternative low-temperature combustion strategies, this paper presents a comparison of three alternative low-temperature combustion strategies to two high-temperature conventional diesel combustion conditions. The baseline conditions, representative of conventional high-temperature diesel combustion, have either a short or a long ignition delay. The other three conditions are representative of some alternative combustion strategies, employing significant charge-gas dilution along with either early or late fuel injection, or a combination of both (double-injection). These operating conditions are investigated for soot volume fraction, soot temperatures, calculated adiabatic flame temperatures, and soot radiation heat loss through 2-color soot thermometry experiments. The spatial location of in-cylinder soot is imaged using a high-speed CMOS camera, and exhaust-gas NO x is also measured. The soot thermometry and high-speed soot luminosity imaging show that the low-temperature operating conditions have lower in-cylinder soot than the high-temperature conditions. Also, soot is formed upstream in the jet for high-temperature operating conditions, but for low-temperature operating conditions, the soot is formed farther downstream, closer to the bowl edge. For all conditions, the onset of in-cylinder soot occurs after the premixed bum, during the mixing-controlled combustion phase. As the amount of soot decreases, the radiation heat loss also decreases drastically. For conventional diesel diffusion combustion operating condition, radiation from soot is about 1.1 percent of the total fuel energy, but for low-temperature combustion operating conditions, the soot radiative heat loss is almost negligible (≈ 0.01 percent). The condition with high soot radiation had peak soot temperatures as much as 300 K lower than the peak adiabatic flame temperatures near 2700 K, and exhaust NO x emissions were near 600 ppm. For the low-temperature conditions, the peak soot temperatures were only about 200 K lower than the peak adiabatic temperatures near 2200 K, and the exhaust NO x concentrations were less than 10 ppm.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"35 1","pages":"1605-1621"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81192573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Achievement of Low Emissions by Engine Modification to Utilize Gas-to-Liquid Fuel and Advanced Emission Controls on a Class 8 Truck","authors":"T. Alleman, C. J. Tennant, R. Hayes, M. Miyasato, A. Oshinuga, Greg Barton, M. Rumminger, V. Duggal, Christopher Nelson, M. May, R. A. Cherrillo","doi":"10.4271/2005-01-3766","DOIUrl":"https://doi.org/10.4271/2005-01-3766","url":null,"abstract":"A 2002 Cummins ISM engine was modified to be optimized for operation on gas-to-liquid (GTL) fuel and advanced emission control devices. The engine modifications included increased exhaust gas recirculation (EGR), decreased compression ratio, and reshaped piston and bowl configuration.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"9 1","pages":"1609-1619"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75916010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Development of Predictive Models for Non-Acidic Lubricity Agents (NALA) using Quantitative Structure Activity Relationships (QSAR)","authors":"D. Barr, Christopher L. Friend","doi":"10.4271/2005-01-3900","DOIUrl":"https://doi.org/10.4271/2005-01-3900","url":null,"abstract":"This study describes the use of Quantitative Structure Activity Relationships (QSAR) to develop predictive models for non-acidic Lubricity agents. The work demonstrates the importance of separating certain chemical families to give better and more robust equations rather than grouping a whole data set together. These models can then be used as important tools in further development work by predicting activities of new compounds before actual synthesis/testing.","PeriodicalId":21404,"journal":{"name":"SAE transactions","volume":"58 1","pages":"1845-1856"},"PeriodicalIF":0.0,"publicationDate":"2005-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76960383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}