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Technical Paper

Numerical study of catalytic methanation reactions using a kinetic model

2024-09-18
2024-24-0022
The main element for the increase in atmospheric temperature is assumed to be the increase of CO2 concentration. Hence, it is essential to reintegrate the secondary products like H2 and CO2 into the energy supply so that the direct CO2 emission can be reduced. A promising approach for a CO2 neutral production circle is the conversion of CO2 into methane, commonly known as methanation. To make the SNG production a recycling process, the exhaust CO2 emitted by a lignite power plant, a refinery, or a cement production plant can be used as a CO2 source to fully convert the hydrogen/CO2 to methane as done by the Sabatier reaction. The Sabatier reaction is thermodynamically favoured, nevertheless the reaction is limited in kinetics and hence catalysts are needed to achieve acceptable conversion from CO2 into CH4. Hence, to understand the complex methanation process, we thoroughly discuss the CO2 methanation to maximize the methane formation and minimize the CO formation.
Technical Paper

Glow-discharge Optical Emission Spectroscopy Study of Cr(III) Sealing in Anodized Aluminium-Silicon Alloys for Brake Component

2024-09-08
2024-01-3038
Calipers and pistons for high-end car braking systems are typically realized using anodized Aluminium-Silicon alloys. Indeed, Aluminium-Silicon alloys are light materials with optimal mechanical properties and, when anodized, excellent corrosion and wear resistances. To achieve these top-notch surface properties, the anodizing process is followed by a sealing post-treatment, which significantly improves the corrosion resistance and tunes the tribological properties (e.g., hardness and friction coefficient) of the anodized pieces. Sealing consists in the precipitation of insoluble hydroxides and functional compounds (e.g., corrosion inhibitors) inside the nano-pores of the anodic layer. Nevertheless, sealing might not penetrate through all the nano-porous structure of the anodic layer. Thus, in light of possible post-machining of sealed, anodized components, it appears fundamental to develop a tool to determine the depth penetration of sealing inside the anodic layer.
Technical Paper

Piston and Guide-Pin Rattle Noise Mitigation in Electro-Mechanical Brake Caliper

2024-09-08
2024-01-3032
The hydraulic brake caliper utilizes pressurized brake fluid to actuate one or multiple pistons generating friction between the brake pads and disc. Calipers are classified into floating and fixed type caliper. Floating caliper slides inboard/outboard direction to apply and release pressure on the outer pad. This type of caliper has rubber or spring components to maintain specific clearance for sliding characteristics. Therefore, caliper rattle noise could occur due to wheel vibrations when the vehicle is driven on unpaved roads or rough surfaces. Rattle noise is particularly pronounced in front calipers positioned closer to the driver and its susceptibility tends to increase with the weight of the caliper. The Electro-Mechanical Brake (EMB) caliper has gained substantial attention in automotive industry for its advantages features including reduced brake drag, optimized vehicle layout and precise brake control.

2024-07-24

Leadership - Powertrains, Fuels & Lubricants Meeting

2024-07-24
PF&L is priority event for mobility professionals that specialize in powertrain, fuels, lubricants technology, including OEM and Tier 1 component suppliers Light medium and heavy-duty vehicle system and product design engineers

2024-07-24

2024-07-24

Attend - Powertrains, Fuels & Lubricants Meeting

2024-07-24
PF&L is priority event for mobility professionals that specialize in powertrain, fuels, lubricants technology, including OEM and Tier 1 component suppliers Light medium and heavy-duty vehicle system and product design engineers

Contact - Powertrains, Fuels & Lubricants Meeting

2024-07-24
PF&L is priority event for mobility professionals that specialize in powertrain, fuels, lubricants technology, including OEM and Tier 1 component suppliers Light medium and heavy-duty vehicle system and product design engineers
Technical Paper

A Computational Study of Hydrogen Direct Injection Using a Pre-Chamber in an Opposed-Piston Engine

2024-07-02
2024-01-3010
Combustion characteristics of a hydrogen (H2) direct-injected (DI) pre-chamber (PC)-assisted opposed piston two-stroke (OP2S) engine are investigated by 3D computational fluid dynamics (CFD) simulations. The architecture of the OP2S engine has potential features for reducing wall heat losses, as the DI H2 jets are not directed towards the piston face. To overcome the high resistance to autoignition of H2, a PC technology was implemented in order to enhance the ignition of the mixture by the multiple hot reactive jets. To further investigate the interaction between the H2 plume and the chamber walls, three different piston bowl designs were evaluated and ranked based on a merit function. For the cases under study, the flat piston design was found to be most favorable (compared to the narrow and wide pistons) due to its reduced surface area for lower wall heat losses.
Technical Paper

Effect of Dithering on Post-Catalyst Exhaust Gas Composition and on Short Time Regeneration of Deactivated PdO/Al2O3 Catalysts under Real Engine Conditions

2024-06-12
2024-37-0002
Fossil fuels such as natural gas used in engines still play an important role worldwide which however is also exacerbating climate change as a result of carbon dioxide emissions. Although natural gas engines show an overall low pollutant emissions level, methane slip due to incomplete combustion occurs, causing methane emissions with a more than 20 times higher global warming potential than CO2. Additionally, further tightening of emissions legislation is to be expected bringing methane emissions even more into focus making exhaust gas aftertreatment issues remain relevant. For lean gas applications, (Pd)-based catalysts turned out to convert CH4 most efficiently usually being supported by metal oxides such as aluminium oxide (Al2O3). Water (H2O) contained in the exhaust gas causes strong inhibition on Pd catalysts.
Technical Paper

Experimental Study of Lignin Fuels for CI Engines

2024-06-12
2024-37-0022
This study explores the feasibility of using a sustainable lignin-based fuel, consisting of 44 % lignin, 50 % ethanol, and 6 % water, in conventional compression ignition (CI) marine engines. Through experimental evaluations on a modified small-bore CI engine, we identified the primary challenges associated with lignin-based fuel, including engine startup and shutdown issues due to solvent evaporation and lignin solidification inside the fuel system, and deposit formation on cylinder walls leading to piston ring seizure. To address these issues, we developed a fuel switching system transitioning from lignin-based fuel to cleaning fuel with 85 vol% of acetone, 10 vol% of water and 5 vol% of ignition improving additive, effectively preventing system clogs.
Technical Paper

Influences of High-Pressure Pump and Injector Nozzle Geometry on Hydraulics Characteristics of a Mechanical Diesel Direct-Injection System

2024-06-04
2024-01-5061
The geometry of high-pressure pump and injector nozzles crucially influences hydraulic behaviors (e.g., the start of injection, the pressure profiles developed in the high-pressure line, needle lift, and injection rates) in diesel engines. These factors, in turn, significantly impact fuel atomization, fuel–air mixing, combustion quality, and the formation of emissions. The main geometry parameters such as plunger diameter and the number and diameter of nozzles lead to the system complexity, requiring careful analysis, design, and calibration. In this study, a high-speed shadowgraph system and a high-resolution pressure recording system were developed to capture the start of injection, spray structure, and pressure profiles in the high-pressure line. Additionally, a model was developed using GT-Fuel package built within the GT-Suite of simulation tools to explore different plunger diameters and numbers and diameters of injector nozzles.
Standard

Test Method for the Determination of Water Concentration in Polyol Ester and Diester Aerospace Lubricants by Coulometric Karl Fischer Titration

2024-05-17
CURRENT
ARP5991B
The test method describes the procedure for the direct determination of water concentration in polyol ester and diester based aerospace lubricants by commercially available automated coulometric Karl Fischer titration instruments. The method was validated to cover the water concentration range of 150 to 3500 µg/g. The method may also be suitable for the determination of water concentrations outside this range and for other classes of fluids; however, the precision statement shall not be applicable for such uses.
Journal Article

Dimethyl Ether Biogas Reactivity-Controlled Compression Ignition for Sustainable Power Generation with Low Nitrogen Oxide Emissions

2024-04-22
Abstract Biogas (60% methane–40% CO2 approximately) can be used in the reactivity-controlled compression ignition (RCCI) mode along with a high-reactivity fuel (HRF). In this work dimethyl ether (DME) that can also be produced from renewable sources was used as the HRF as a move toward sustainable power generation. The two-cylinder turbocharged diesel engine modified to work in the DME–biogas RCCI (DMB-RCCI) mode was studied under different proportions of methane (45–95%) in biogas since the quality of this fuel can vary depending on the feedstock and production method. Only a narrow range of biogas to DME ratios could be tolerated in this mode at each output without misfire or knock. Detailed experiments were conducted at brake mean effective pressures (BMEPs) of 3 and 5 bar at a speed of 1500 rpm and comparisons were made with the diesel–biogas dual-fuel and diesel–biogas RCCI modes under similar methane flow rates while the proportion of CO2 was varied.
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