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Viewing 1 to 30 of 251
2017-03-28
Journal Article
2017-01-0411
Yuming Yin, Subhash Rakheja, Jue Yang, P-E. Boileau
Abstract This study is aimed at characterizing the nonlinear stiffness and damping properties of a simple and low cost design of a hydro-pneumatic suspension (HPS) that permits entrapment of gas into the hydraulic fluid. The mixing of gas into the oil yields highly complex variations in the bulk modulus, density and viscosity of the hydraulic fluid, and the effective gas pressure, which are generally neglected. The pseudo-static and dynamic properties of the HPS strut were investigated experimentally and analytically. Laboratory tests were conducted to measure responses in terms of total force and fluid pressures within each chamber under harmonic excitations and nearly steady temperature. The measured data revealed gradual entrapment of gas in the hydraulic fluid until the mean pressure saturated at about 84% of the initial pressure, suggesting considerably reduced effective bulk modulus and density of the hydraulic fluid.
2016-04-05
Technical Paper
2016-01-0196
Sivanandi Rajadurai, Madhusudhanan Paulraj, Alrin Maria Victor
Abstract The numerical methodology is developed to estimate the backpressure value acquired from the cold flow bench into the hot flow conditions by equalizing various gas flow properties such as gas density and gas constant. The exhaust muffler geometry is adopted for virtual analysis. Computational Fluid Dynamics (CFD) modeling of the exhaust muffler in hot and cold flow conditions shows 60% of difference in back pressure values. The same muffler sample is tested in hot and cold flow test bench for back pressure on same measurement location used in CFD tool, the test result difference between these two conditions is obtained as 61%. By using derived 1D calculation, the cold flow back pressure results are extrapolated to generate hot flow back pressure values for the exhaust muffler system. These extrapolated values are then validated with the back pressure analysis results performed in both CFD and flow test bench using cold and hot flow conditions.
2015-09-01
Technical Paper
2015-01-2002
Takeshi Yokomori, Haruko Nagai, Hiroshi Shiratori, Naoki Shino, Naoki Fujisawa, Taro Hirasawa
This study reports a novel alternative technique that can achieve simultaneous two-dimensional temperature and velocity measurements in gas flow. This method is combining phosphor thermometry and PIV operated by a single laser unit. The temperature distribution was obtained from phosphorescence by using two-color method, and the velocity distribution was obtained from two phosphor particle images which were taken in time series during the persistence of the phosphorescence. The measured temperature and velocity were agreed with that measured by thermocouple and that expected as theoretical distribution in the high-temperature gas flows, respectively.
2014-04-01
Technical Paper
2014-01-1576
Nehemiah Sabinus Alozie, David Peirce, Lionel Ganippa
Abstract When assessing particulate emissions, diesel engine exhausts are usually diluted to suit the design limitations of the measurement devices. Particle number concentrations (PNC) are known to be sensitive to dilution conditions and must be considered when evaluating results. Laboratories employ various experimental techniques to dilute exhaust samples before measurements. The majority of measurement systems use air as dilution a gas, some employ filtered exhaust gas in a closed loop, while others employ nitrogen, where prevention of oxidation reaction is required. In this work, the effect of using air and nitrogen as dilution gases on the PNCs from diesel engine exhausts has been investigated. Our approach explored the use of carbon dioxide (CO2) concentration ratios in diluted and raw exhaust samples, evaluated by non-dispersive infrared (NDIR) analysers to determine dilution conditions of the measured sample.
2014-04-01
Technical Paper
2014-01-1414
Weidi Huang, Zhijun Wu, Liguang Li, Zongjie Hu, Ya Gao, Jun Deng
Abstract In this study, in order to form a wide range of ambient gas density, Nitrogen and sulfur hexafluoride (SF6) are employed as ambient gas. Based on the common rail and high speed imaging system, the spray characteristics in extremely high ambient density and different ambient temperature are investigated in a constant volume vessel, and the influences of gas physical property on the spray characteristics have also been analyzed. The investigation results show that: the spray tip penetration and spray cone angle vary phenomenally with the increase of the ambient gas density. Due to the generation of shock wave, the results of the spray characteristics from two ambient gas densities are different nevertheless the same densities. Furthermore, the spray tip penetrations from the different ambient gases do not vary obviously from each other until the detachment of the shock wave from the spray tip.
2013-10-15
Technical Paper
2013-32-9116
Hiroshi Enomoto, Shogo Kunioka, Lukas Kano Mangalla, Noboru Hieda
An experimental study has been conducted at small kerosene droplet behavior near well-defined butane diffusion flame for the critical need on high efficient and cleaner energy technology. High temperature of background gas was generated using butane flame. Microflame from butane can reach the maximum temperature around 1200K at tip of outer glass. Single droplet of kerosene was injected by a small injector tube (30 μm-diameter) in to hot environment. Droplet of kerosene was released by attachment of piezo actuator on wall injector. Once the droplet is exposed to the hot atmosphere of micro flame, the temporal regression of the droplet surface was recorded. Droplet diameter was observed by CCD camera with strobe light flash at 180ns. The images captured in this experiment were analyzed by post-processing software to determine the vaporization of droplet.
2013-10-15
Technical Paper
2013-32-9117
Hiroshi Enomoto, Shunsuke Sawasaki, Kosuke Nishioka, Lukas Kano Mangalla
In this study, the background gas of the droplet vaporization was concerned and simulated numerically using ANSYS fluent code. The new type, engine-like, condition of high pressure chamber and high temperature environment was considered to conduct experiment on kerosene droplet evaporation. 2D geometry of domain simulation was discretized in the very fine quadrilateral meshes. The numerical approach was solved using implicit scheme of compressible gas solver (density based). Temperature dependent properties of air are expressed for gas material properties. As the study concerning on high pressure condition the equation state of Peng-Robinson was expressed in simulation. Governing equations of mass, momentum and energy were solved by the second order upwind for flow, turbulent kinetic energy and turbulent dissipation rate. Standard k-ε model was used to solve turbulence flow in the spatial discretization.
2013-10-15
Technical Paper
2013-32-9123
Hiroshi Enomoto, Shogo Kunioka, Noboru Hieda
In this paper, droplet behavior near diffusion flame was observed. Single droplet was created by thin glass tube and piezo device which pushes the side of glass tube. Dispersions of droplets location near diffusive flame were compared to droplets with no flame condition. CCD camera, strobe light with 180nsec flash time and lens of ten magnification were used for observation. Droplet pictures were taken with resolution of 0.46um/pix. As a result, droplets near diffusive flame tend to increase its dispersion of location as approaching tip of the flame. Stefan flow caused by evaporation and turbulence outer flow can be thought as causes.
2013-03-25
Technical Paper
2013-01-0104
Tuan Le Anh, Khanh Nguyen Duc, Huong Tran Thi Thu, Tai Cao Van
Recently, using hydrogen or hydrogen-rich gas as a supplement fuel for spark ignition and compression ignition engines is one of the potential solutions for improving brake thermal efficiency, reducing fuel consumption and pollution emissions from internal combustion engines. This article investigates the effect of HHO gas addition on engine performance and emission characteristics. HHO gas was produced by the electrolysis process of distilled water and stored in a high pressure tank before injected into the intake manifold. The experimental study was carried out on a 97 cc SI engine equipped with two injection systems (HHO gas and addition air) on the intake manifold. The tests were divided into two cases: hybrid HHO/gasoline and HHO/gasoline with addition air from second injection.
2013-01-09
Technical Paper
2013-26-0001
Ewa Rostek, Krzysztof Biernat
The article presented the processes of pyrolysis and gasification of biomass leading to the preparation of liquid hydrocarbon fractions in the synthesis of Fischer-Tropsch and processes HTU. Preliminary thermogravimetric testing of biomass samples was conducted on the STA 449 F3 Jupiter® coupled with the gases analyzer - spectrometer QMS 403 Aëolos. These studies were carried out for samples of cereal straw, crushed to a state of dry dust. The temperature regime provided that the samples were heated to the temperature of 750°C at the heating rate of 10 K/min. Gases (nitrogen, argon or carbon dioxide) were used with flow rates of 60 ml/min. The results, along with discussion, are presented in graphs - TG curves and mass spectrum.
2012-04-16
Technical Paper
2012-01-0444
Jan Czerwinski, Pierre Comte, Thomas Hilfiker, Andreas Fürholz
In order to analyze the processes during the gas exchange in the engine, knowledge of pressure states in both inlet and outlet is required. This pressure measuring is known as “low pressure indication”. In the present work, three examples of controlling the quality of low pressure measurement are presented. An insight in the pressure waves in exhaust pipe, especially in the exhaust blow-off is given. It was shown that: a small inaccuracy of measurement, lower than 10 mbar can be attained, the asymmetric course of the exhaust pulse can clearly be verified, and a protection screen for a sensor exposed to the exhaust blow-off pressure wave can be a tool to optimize between longlife and accuracy. The most important statements are: both presented methods of low pressure indication - the direkt and the indirect yield the results with highest accuracy.
2012-01-09
Technical Paper
2012-28-0020
Pravin V. Yarsam, Abhijit. A. Athawale, Milind. D. Peshave, S. N. Sapali
The power output of an internal combustion engine is directly proportional to the amount of air that can be forced into the cylinder per cycle and the amount of fuel that can be burned efficiently. The amount of air is most effectively increased by means of a mechanical supercharger. The purpose of this paper is attempting the non mechanical supercharging ways (Supercharging by means of gas dynamic effects) for naturally aspirated (NA) diesel engines and understanding in a better way the induction gas dynamics and its influence on engine performance characteristics. Wave dynamics in the intake system has strong influence on the performance of naturally aspirated internal combustion (IC) engines. This paper presents an application of Helmholtz resonator in the induction system of the naturally aspirated diesel engine to improve the engine breathing efficiency (volumetric efficiency).
2011-10-06
Technical Paper
2011-28-0044
Byan Wahyu Riyandwita, Myung-whan Bae, Elvira Fidelia Tanjung, Kazuo Tsuchiya
It is important to understand the influence of gas transport properties on the process of urea gas decomposition in the modeling of a urea-SCR system. The purpose of this study is to find the gas transport property that exerts the strongest influence on the process of urea gas decomposition in a urea-SCR system using a three-dimensional model with the laminar flow of incompressible viscous gas at a steady-state condition by the SIMPLE algorithm. It is found that the gas transport properties which have the strongest influence on the process of urea gas decomposition in a urea-SCR system are the density and molecular diffusivity. It is also found that the influence of density is stronger than the molecular diffusivity at low temperature ranges. In contrary, the molecular diffusivity has stronger influence at high temperature ranges comparing with the density.
2011-01-19
Technical Paper
2011-26-0034
S. Suresh Bagavathy, N. Balasubramanian, D. Premnath, S. Krishnan
The objective of the diesel engine development program is not only providing the maximum thermal efficiency but also to meet future stringent emission targets. The focus should be on controlling and reducing the unburned emissions, especially blow-by emission apart from controlling burnt emissions. In some extreme cases blow-by may contribute up to 50% of the total oil consumption of the engine. These blow-by emissions are the responsible phenomena for the engine operation, the economy and ecology expressed through the oil consumption and oil change interval rates. Engine breathing system is the most complex circuit within the engine, the air entrapment into space above oil in engine system is pushing more oil from sump. This should be avoided. In effect of controlling these factors the engine breathing system should be properly designed and maintained.
2011-01-19
Technical Paper
2011-26-0024
C. Khandai, Amar Bakare, R. M. Petkar, K. V. R. Babu, Chris Dias, Alfred Reck
Diesel engines tend to operate on lower exhaust temperatures, compared to their gasoline counterparts. Exhaust emission control becomes a significant issue at these lower temperatures, as any catalytic converter needs certain light off temperature to commence functioning. The trend so far has been to move the catalytic converters closer to the exhaust manifold, in order to get the benefit of higher temperatures - but most of the applications are limited to the location available after the turbo chargers. This is due the fact that very minute and efficient catalyst is required, if it has to be placed before the turbo charger. This catalyst also needs to be extremely durable to take care of high exotherms which occur within the catalysts and also to prevent any possible damage to the turbo chargers.
2011-01-19
Technical Paper
2011-26-0044
Montajir Rahman, Kenji Hara, Shigeru Nakatani, Yoshimasa Tanaka
An analyzer based on Quantum Cascade Laser (QCL) has been developed for chemical sensing of gaseous nitrogen compounds (NO, NO₂, N₂O and NH₃). The QCL can emit coherent lights in the Mid-infrared (Mid-IR) region where these nitrogen compounds exhibit strong absorption tendency. Therefore, it is possible to detect very low concentration gas. QCL can also give a super fine resolution of the spectrum in this region. Therefore, utilization of this spectrometer can reduce the interference caused by the spectral overlap of coexisting gases in automobile engine exhaust. In the previous study, the fundamental concept of development along with some basic performance of the analyzer had been reported. In this study, improvement of performance has been attempted. Especially, the cell design, response time of NH₃, broadening the measurement ranges, and increasing the data sampling speed have been considered.
2011-01-19
Technical Paper
2011-26-0029
Alain Ristori, Paul Spurk, Marcus Pfeiffer, Frank Schütze, P. Tancell, Sudipto Basu
With the implementation of Euro V emissions legislation in 2010, the vast majority of light-duty diesel vehicles now employ a diesel particulate filter. The expansion of the Diesel Euro V standard outside Europe is inhibited in part by the low availability of ≺50 ppm sulfur fuel. Having said this, countries such as India and China have ≺50 ppm sulfur fuel available in many urban centers today, with the geographical area covered growing each year. Whilst it is well known that diesel DPF applications require ≺50 ppm sulfur fuel for optimum long-term operation, the ability of the system to withstand periodic "high" sulfur events would be a useful enabler for the early implementation of Euro V legislation to these markets. In this paper, the authors set out to assess the capability of the DOC and cDPF exhaust gas aftertreatment system to cope with periodic high sulfur fuel events.
2011-01-19
Technical Paper
2011-26-0007
Bipin Bihari, Steenath B. Gupta, Munidhar Biruduganti, Raj R. Sekar
Two diagnostics were developed that are particularly suitable for use with natural gas-fuelled reciprocating engines that are used for power generation applications. The first diagnostic relates flame chemiluminescence to thermodynamic metrics relevant to engine combustion - Heat Release Rate (HRR) and in-cylinder bulk gas temperature. Studies were conducted in a single-cylinder natural gas-fired reciprocating engine that could simulate turbocharged conditions with Exhaust Gas Recirculation. Crank-angle-resolved spectra (266 to 795 nm) of flame luminosity were measured for various operational conditions by varying the ignition timing for MBT conditions and by holding the speed at 1800 rpm and Brake Mean Effective Pressure (BMEP) at 12 bar. The effect of dilution on CO₂* chemiluminescence intensities was studied, by varying the global equivalence ratio (0.6 - 1.0) and by varying the Exhaust Gas Recirculation rate.
2011-01-19
Technical Paper
2011-26-0001
A. Shah, S. S. Thipse, A. Tyagi, S. D. Rairikar, K. P. Kavthekar, N. V. Marathe, Padmesh Mandloi
Dual fuel operating strategy offers great opportunity to reduce emissions like particulate matter and NOx from compression ignition engine and use of clearer fuels like natural gas. Dual-fuel engines have number of potential advantages like fuel flexibility, lower emissions, higher compression ratio, better efficiency and easy conversion of existing diesel engines without major hardware modifications. In view of energy depletion and environmental pollution, dual-fuel technology has caught attention of researchers. It is an ecological and efficient combustion technology. This paper summarizes a review of recent research on dual-fuel technology and future scope of research. Paper also throws light on present limitations and drawbacks of dual-fuel engines and proposed methods to overcome these drawbacks. A parametric study of different engine-operating variables affecting performance of diesel-CNG dual-fuel engines vis-à-vis base diesel operation is also summarized here.
2011-01-19
Technical Paper
2011-26-0084
B. Dinesh Kumar, A. Senthil Kumar, K. C. Vora
In this work a simple 1-D model for the macro kinetic conversion behaviour of a commercial automotive Three-way-exhaust catalyst for a Turbocharged DI-Gasoline-Engine is realized using GT-Power. A detailed reaction kinetic model to predict the activity of the commercial three way catalyst has been adopted from Young-Deuk [1], considering all possible reactions in the catalytic converter based upon the Langmuir-Hinshelwood mechanism. 1D model was later modified for the laboratory scale catalyst and validated against synthetic gas test bench data.
2009-11-03
Technical Paper
2009-32-0032
TEOH Yew Heng, Horizon GITANO-BRIGGS, TAN Yee Hern
It is well known that conventional carbureted two-stroke engines have high exhaust emission and poor fuel efficiency. To solve these problems direct gaseous fuel injection (DI) was introduced as a lower cost alternative to the gasoline direct injection (GDI) System. In this paper we investigate the use of liquefied petroleum gas (LPG) as a fuel in terms of lean combustion operation, and focus on analysis of in cylinder combustion pressure, fuel mass fraction burned, engine performance and exhaust emissions. Results are compared for various injection timings from premixed (early injection) to fully direct injection mode (late injection). Results show that late start of injection timing causes the torque to drop off significantly and poorer exhaust emission, mainly due to poor mixing of gaseous fuel and air. The DI of gaseous fuel effectively reduces exhaust emission and can substantially improve the fuel economy of two-stroke engines.
2009-11-03
Technical Paper
2009-32-0026
How Heoy Geok, Taib Iskandar Mohamad, Shahrir Abdullah, Yusoff Ali, Azhari Shamsudeen
A single cylinder port injection gasoline engine was converted to a bi-fuel gasoline-compressed natural gas operation. The engine was run at wide open throttle and speeds ranging from 1500 to 5000 rpm. Cylinder pressure and air-fuel flow rate were recorded to calculate the indicated performance. Results show CNG operation yields higher FCE and lower ISFC. However, the indicated power, indicated torque, IMEP and volumetric efficiency of CNG were reduced due to lower charge density and slower flame speed. In terms of exhaust emissions, CNG shows significantly lower emission of HC, CO2 and CO. The NOx emission however shows mixed behavior.
2009-11-03
Technical Paper
2009-32-0101
Oliver Schögl, Stephan Schmidt, Martin Abart, Roland Kirchberger, Matthias Fitl, Philipp Gschwantner
In the early phase of an engine development process, the main characteristics of an engine setup, such as lengths, diameter and volumes, are usually defined by means of 1D CFD simulation technologies. Only single flow situations are modeled in 3D due to the high expenditure of time and money. This paper presents a new efficient development methodology using 1D, 3D as well as coupled 1D/3D simulation techniques - the described simulation strategy leads to a more realistic and more comparable reproduction of the flow situation, especially in the critical areas of the simulation domain, while avoiding the restrictions and disadvantages of 1D and 3D simulation. By the use of test bench results of a comparable prototype engine, the quality of the simulation strategy has been successfully verified.
2009-11-03
Technical Paper
2009-32-0085
Daisuke Shirota, Norimasa Iida
Thermal and mixing stratifications have been thought as one of the ways to avoid an excessive pressure rise on HCCI combustion. The purpose of this research is to investigate the potential of thermal and mixing stratifications for reducing PRR (Pressure Rise Rate) on HCCI combustion. The pre-mixture with thermal and mixing stratifications is charged in RCM (Rapid Compression Machine). After that, the pre-mixture is compressed and in that process, in-cylinder gas pressure and chemiluminescence images are obtained and analyzed. Furthermore, experimental results are compared with the computational results calculated by using multi-zone model for analyzing these mechanisms.
2009-11-03
Technical Paper
2009-32-0074
Emishaw D. Iffa, A. Rashid A. Aziz
The complicated In-cylinder varying density field behavior of gaseous fuels makes the air fuel mixing process difficult to study. This problem urges to find out the injected gaseous fuel density distribution. This paper tries to find out the normalized injected CNG density distribution at small injection pressure. Background oriented schlieren and image processing techniques are implemented to find the variable density distribution on a constant volume chamber during injection.
2009-11-03
Technical Paper
2009-32-0066
Yudai YAMASAKI, Masanobu KANNO, Yasuhiro TAURA, Shigehiko KANEKO
Autoignition and combustion characteristics of biomass gas were investigated experimentally. A mock biomass gas consisting of H2, CH4, CO, N2 and CO2 was used as a wood pyrolysis gas. Experiments were carried out with a modified gas engine varying equivalence ratio and fuel composition. High hydrogen content increases the combustion speed, but it hardly affects ignition timing. Carbon monoxide in fuels does not affect combustion speed largely. The autoignition temperature of biomass gas is about 1000K, which is the same as those of hydrocarbon fuels. The engine also realizes 42% of the indicated thermal efficiency and a maximum IMEP of 0.3MPa.
2009-11-02
Technical Paper
2009-01-2740
Kentaro Misawa, Shun-ichi Ishiuchi, Masaaki Fujii, Jun Matsumoto, Koichi Tanaka, Jun Nakagawa, Katsumi Endo, Shun-ichi Hayashi, Kotaro Tanaka, HiroYuki Yamada, Yuichi Goto
Real-time analysis of benzene in automobile exhaust gas was performed using the Jet-REMPI (supersonic jet / resonance enhanced multi-photon ionization) method. Real-time benzene concentration of two diesel trucks and one gasoline vehicle driving in Japanese driving modes were observed under ppm level at 1 s intervals. As a result, it became obvious that there were many differences in their emission tendencies, because of their car types, driving conditions, and catalyst conditions. In two diesel vehicle, benzene emission tendencies were opposite. And, in a gasoline vehicle, emission pattern were different between hot and cold conditions due to the catalyst conditions.
2009-11-02
Technical Paper
2009-01-2727
Craig Wildman, Robert J. Scaringe, Wai Cheng
This paper explores the combined effects of boosting, intake air temperature, trapped residual gas fraction, and dilution on the Maximum Pressure Rise Rate (MPRR) in a boosted single cylinder gasoline HCCI engine with combustion controlled by negative valve overlap. Dilutions by both air and by cooled EGR were used. Because of the sensitivity of MPRR to boost, the MPRR constrained maximum load (as measured by the NIMEP) did not necessarily increase with boosting. At the same intake temperature and trapped residual gas fraction, dilution by recirculated burn gas was effective in reducing the MPRR, but dilution by air increased the value of MPRR. The dependence of MPRR on the operating condition was interpreted successfully by a simple thermodynamic analysis that related the MPRR value to the volumetric heat release rate.
2009-11-02
Journal Article
2009-01-2698
Johannes Arning, Tashiv Ramsander, Nick Collings
Gasoline Homogeneous Charge Compression Ignition (HCCI) combustion has been studied widely in the past decade. However, in HCCI engines using negative valve overlap (NVO), there is still uncertainty as to whether the effect of pilot injection during NVO on the start of combustion is primarily due to heat release of the pilot fuel during NVO or whether it is due to pilot fuel reformation. This paper presents data taken on a 4-cylinder gasoline direct injection, spark ignition/HCCI engine with a dual cam system, capable of recompressing residual gas. Engine in-cylinder samples are extracted at various points during the engine cycle through a high-speed sampling system and directly analysed with a gas chromatograph and flame ionisation detector. Engine parameter sweeps are performed for different pilot injection timings and quantities at a medium load point.
2009-09-13
Technical Paper
2009-24-0115
M. Davy, R.L. Evans, A. Mezo
It is well known that lean operation of homogeneous- charge spark-ignited engines is effective in increasing thermal efficiency and reducing exhaust emissions. In particular, the lower combustion temperatures provided by a lean air-fuel mixture result in a significant reduction in NOx emissions. Lean operation is normally restricted, however, by the “lean-limit” of combustion, as measured by the air-fuel ratio above which ignition is impossible, or combustion is incomplete. In order to extend the lean limit of operation a new “partially-stratified charge” combustion concept has been developed. This technique relies on the fact that a stronger initial flame kernel produced following the spark event should also be effective in igniting a very lean mixture which may not otherwise ignite, or which may result in incomplete combustion.
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