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Inverse Vibration Problem Used for the Characterization of the Damping Added by a Trim Foam on a Plate

CEVAA-Nicolas Merlette
CEVAA, LAUM-Meryem LE DEUNF
  • Technical Paper
  • 2020-01-1580
To be published on 2020-06-03 by SAE International in United States
Many solutions exist to insure the NVH comfort of ground and air vehicles, like heavy mass (bitumen pads), viscoelastic treatments and absorbing foams. The trim foam is an alternative to heavy solutions. To know the potential of the foam, a study of its capacity to damp vibration is done. A system, composed by a suspended plate, with a foam on it, is characterized in different cases of contact at the foam-plate interface (glued or not) and with different types of foam. An experimental test facility is developed to identify the global damping of the structure: a laser vibrometer measures the displacement field of the foam-plate structure, an inverse method is used to determine the structural parameters. By changing the contact at the interface, it is possible to identify the contribution of the friction forces to the global damping of the structure. Another type of damping is the viscoelastic damping due to the intrinsic characteristics of the trim foam. With the help of FEA, it is possible to understand the influence of the damping effect. The…
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Ammonia Measurement Investigation Using Quantum Cascade Laser and Two Different Fourier Transform Infrared Spectroscopy Methods

Caterpillar UK Ltd-Richard Barrett, Jim Baxter
Loughborough university-Nilton Li, Ashraf El-Hamalawi
  • Technical Paper
  • 2020-01-0365
To be published on 2020-04-14 by SAE International in United States
Most diesel engine exhausts have been fitted with SCR (Selective Catalyst Reduction) in order to reduce NOX (Oxides of Nitrogen) by using NH3 (ammonia). However, both NOX and NH3 have been classified as compounds hazardous for the environment and human health. If the reaction between NOX and NH3 is unbalanced during treatment, it can lead to either NOX or NH3 being released into the environment. Accurate measurement is thus necessary. QCL (Quantum Cascade Laser) and FTIR (Fourier Transform InfraRed) are two methods that have been used to measure NH3 and NOX directly in diesel engine exhausts. However, only a few studies have compared those two methods of NH3 measurement, mainly from diesel engine exhausts. The aim of this paper is to compare the QCL and 2 different FTIR specifications for NH3 measurement directly from diesel engine exhausts under well-controlled laboratory conditions. Researchers have found that as NH3 is reactive, it is absorbed inside the exhaust pipe if the probe location is some distance away from the SCR. The results reported here contradict this and show…
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LiDAR and Camera-based Convolutional Neural Network Detection for Autonomous Driving

National Research Council Canada-Ismail Hamieh, Ryan Myers, Hisham Nimri, Taufiq Rahman
University of Windsor-Aarron Younan, Brad Sato, Abdul El-Kadri, Selwan Nissan, Kemal Tepe
  • Technical Paper
  • 2020-01-0136
To be published on 2020-04-14 by SAE International in United States
Autonomous vehicles are currently a subject of great interest and there is heavy research on creating and improving algorithms for detecting objects in their vicinity. Object classification and detection are crucial tasks that need to be solved accurately and robustly in order to achieve higher automation levels. Current approaches for classification and detection use either cameras or light detection and ranging (LiDAR) sensors. Cameras can work at high frame-rate, and provide dense information over a long range under good illumination and fair weather. LiDARs scan the environment by using their own emitted pulses of laser light and they are only marginally affected by the external lighting conditions. LiDARs provide accurate distance measurements. However, they have a limited range, typically between 10 and 100 m, and provide sparse data. A ROS-based deep learning approach has been developed to detect objects using point cloud data. With encoded raw camera and LiDAR data, several basic statistics such as elevation and density are generated. The system leverages simple and fast convolutional neural network (CNN) solution for object classification and…
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Effects of n-Butanol Additions on Combustion and Emission Characteristics of HTL and Diesel blends

Beijing Institute of Technology-Ziming Yang
University of Illinois-Timothy Lee, Chia-Fon Lee
  • Technical Paper
  • 2020-01-0393
To be published on 2020-04-14 by SAE International in United States
Biocrude diesel converted from wet biowaste via hydrothermal liquefaction (HTL) is drawing increased attention in recent years due to its wide range of raw materials (algae, swine manure, and food processing waste). However, from the previous experiments done in a constant volume chamber, it was observed that the presence of 20% of HTL in the blend produced as much soot as pure diesel at the ambient oxygen ratio of 21%, and even more soot at low oxygen ratios. It was also observed that n-butanol additions could reduce the soot emissions of diesel significantly under all tested conditions. In this work, the spray and combustion characteristics of HTL and diesel blends with n-butanol added were investigated in a constant volume chamber. The ambient temperature and oxygen ranged from 800 to 1200 K and 13% to 21%, respectively, covering both conventional and low-temperature combustion (LTC) regimes. Time-resolved images of the spray and natural flame luminosity (an indicator of soot) were captured by a high-speed camera coupled with a copper vapor laser beam. The experiments revealed that n-butanol…
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Study on dynamic characteristics of droplet impact on wet wall

Tianjin University-Yuqian Wang, Yiqiang Pei, Jing Qin, Lili Lu, Xiang Li, Zhenshan Peng
  • Technical Paper
  • 2020-01-1429
To be published on 2020-04-14 by SAE International in United States
To better understand the spray impingement on oil substrate and the interaction of the two in a gasoline direct injection engine.It's important to understand the behavior of single droplet impinge on the oil film and composition of the coronal formed by fuel and oil.In this paper, laser induced fluorescence method was used to observe the phenomenon of ethanol droplets impinging on the liquid film of glycerol aqueous solution. The We number of incident droplets, the dynamic viscosity of the liquid film and the dimensionless liquid film thickness were studied. The relationship of fluorescence intensity and coronal composition and the formation mechanisms of coronal and splash were built. Tests have shown that We number have a major promoting effect on crown splash. High liquid film dynamic viscosity and dimensionless liquid film thickness have an inhibitory effect on coronal formation and splash. Under the condition that the We number of incident droplets is equal, the composition of the liquid film in the crown decreases as the dynamic viscosity of the liquid film increases. The proportion of the…
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SUV kinematics during a steer-induced rollover resolved using consumer-grade video, laser scans and match-moving techniques

MEA Forensic Engineers & Scientists-Cole R. Young, David J. King, Gunter P. Siegmund
  • Technical Paper
  • 2020-01-0642
To be published on 2020-04-14 by SAE International in United States
Rollover crashes are complex events that generate motions in all six degrees of freedom. Directly quantifying the angular rotations from video can be difficult and vehicle orientation as a function of time is often not reported for staged rollover crashes. Our goal was to evaluate the ability of using a match-moving technique and consumer-grade video cameras to quantify the roll, pitch and yaw angles and angular velocities of a rollover crash. We staged a steer-induced rollover of an SUV at 106 km/h. The vehicle was fitted with tri-axial accelerometers and angular rate sensors, and five consumer-grade video cameras (2 on tripods, 2 on drones, 1 handheld, ~30 fps) captured the event. Roll, pitch and yaw angles were determined from the video using specialized software. We then compared the vehicle orientation angles from the video data to the integrated angular rate data, and also compared the angular rates from the differentiated video data to the angular rates measured directly by the sensors. We found that both methods of measuring the 3D angles and angular rates generated…
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A New Cavitation Algorithm to Support the Interpretation of LIF Measurements of Piston Rings

Technical University of Munich-Georg Wachtmeister
Technical University of Munich / Tenneco-Fabian H. Ruch
  • Technical Paper
  • 2020-01-1091
To be published on 2020-04-14 by SAE International in United States
To investigate oil transport mechanisms under real engine conditions, laser induced fluorescence (LIF) is used. The engine oil is mixed with a dye that can be induced by a laser. The emitted light intensity from the dye correlates with the residual oil at the sensor position and resulting oil film thicknesses can be determined in high detail for each crank angle. However, the general expectation is not always achieved, e.g. an exact representation of piston ring barrel shapes. In order to investigate the responsible lubrication effects of this behavior, a new cavitation algorithm for the Reynolds equation has been developed. The solution retains the mass conservation and does not use any switch function in its mathematical approach. In contrast to common approaches, no vapor-liquid ratio is used, but one or several bigger bubbles are approximated, as have been observed in other experiments already. As a result, not only the known boundary conditions for the Reynolds equation become unnecessary, but the solution also gives a clearer idea about the shape of the cavitation bubble. The combination…
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Optical study on the fuel spray characteristics of high-pressure isobaric combustion using four consecutive injections

King Abdullah University of Science & Technology-Qinglong Tang, Ramgopal Sampath, Priybrat Sharma, Gustav Nyrenstedt, Abdullah Al Ramadan, Moez Ben Houidi, Bengt Johansson, Gaetano Magnotti
Saudi Aramco-Jihad Badra
  • Technical Paper
  • 2020-01-1129
To be published on 2020-04-14 by SAE International in United States
High-pressure isobaric combustion using the double compression expansion concept was proposed to obtain higher brake thermal efficiency than the conventional diesel combustion. Experiments in metal engines have shown that four consecutive injections delivered by a single injector can achieve isobaric combustion. Improved understanding of the detailed fuel-air mixing with multiple consecutive injections is needed to optimize the isobaric combustion and reduce engine emissions. In this study, we explored the fuel spray characteristics of the four consecutive injections strategy using fuel-tracer planar laser-induced fluorescence (PLIF) imaging on a heavy-duty optical engine under non-reactive condition. Toluene of 2% by volume was added into the n-heptane fuel and served as the tracer. The fourth harmonic of a 10 Hz Nd:YAG laser was applied for excitation of toluene. One of the fuel sprays was bisected by the vertical laser sheet and visualized by a camera from the side view. The PLIF images of the premixed mixture formed by port fuel injection were used to normalize the direct-injection PLIF images and correct the effect of non-uniformity of the laser sheet.…
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Apparent Soot Size and Concentration in Combusting Diesel Jets at High Gas Pressures and Temperatures Measured by Combining Quasi-Simultaneous LII, Elastic Light Scattering and Light Extinction

Chalmers University of Technology-Mats Andersson, Sven Andersson
RISE Research Institutes of Sweden-Raul Ochoterena
  • Technical Paper
  • 2020-01-0787
To be published on 2020-04-14 by SAE International in United States
A method for measuring apparent soot particle size and concentration in turbulent combusting diesel jets with elevated and inhomogeneous optical density is presented and discussed. The method is based on the combination of quasi-simultaneous Laser Induced Incandescence (LII), Elastic Scattering (ELS) and Light Extinction (LE) measurements exhibiting a high potential for spatially resolved measurements of carbonaceous particles in flames and residual gases at a given instant. The method evaluates the LII signal by calculating the laser fluence across the flame and compensating for signal trapping, allowing measurements where laser extinction between the flame borders reaches values up to 90 %. The method was implemented by measuring particle size and concentration in the middle sagittal axis of optically dense, combusting diesel jets at a certain time after the start of combustion. Experiments were carried out in the Chalmers High Pressure, High Temperature spray rig under conditions similar to those prevailing in direct injected compression ignition engines. Measurements of apparent particle size and concentration together with volume fraction conferring an instantaneous single-shot case and an average measurement…
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Impact of multiple injection strategies on efficiency and combustion characteristics in an optical PPC engine

Lund University-Miao Zhang, Leilei Xu, Saeed Derafshzan, Xue-Song Bai, Mattias Richter, Marcus Lundgren
  • Technical Paper
  • 2020-01-1131
To be published on 2020-04-14 by SAE International in United States
The partially premixed combustion (PPC) concept is regarded as an intermediate process between the fully mixed Homogeneous charge compression ignition (HCCI) combustion and compression ignition (CI) combustion. It is also a combination of auto-ignition mode, a fuel-rich premixed mode, and a diffusion combustion mode. To achieve high efficiency and low soot emission, the in-cylinder mixture process and combustion behavior of PPC are still to be further explored using laser diagnostic. In this paper, a combined combustion deriving from three stages (HCCI stage, transition stage, PPC stage) was achieved by using multiple injection strategies changing from -220° to -8° after top dead center (ATDC) in an optical heavy-duty CI engine. To analyze the interaction between different combustion modes from HCCI, PPC, and CI, the natural luminosity of combustion was captured by high speed camera. The result shows that piston bowl and cylinder wall play an important role on mixture process in the transition stage and PPC stage. Besides, the interaction between different combustion modes result in different ignition behavior, combustion propagation and gross indicated efficiency.