Browse Topic: Engine mechanical components

Items (14,780)
Despite the increasing electrification of current vehicles, Diesel engines will continue to be used for several decades to come. There is still a need to introduce emission control technologies, especially those that show good potential and do not require extensive engine modifications. The increasing focus on reducing pollutant emissions and improving energy efficiency has prompted engine manufacturers to continuously strive for technological progress. The aim is to ensure compliance with environmental regulations and the fulfillment of social expectations. Specifically, new Diesel engine projects face the challenge of minimizing both nitrogen oxides (NOx) and soot emissions, which requires significant investiment in research to develop innovative combustion methods and exhaust gas treatment. One of these innovative methods is Ducted Fuel Injection (DFI), which aims to reduce emissions by improving spray development to obtain a better mixture at flame upstream. This study presents an
Dias, Fábio Jairodos Santos, Leila RibeiroRufino, CaioGarcia, Ezio CastejonLomonaco, RaphaelArgachoy, CelsoLacava, Pedro Teixeira
Autonomous vehicles for mining operations offer increased productivity, reduced total cost of ownership, decreased maintenance costs, improved reliability, and reduced operator exposure to harsh mining environments. A large flow of data exists between the remote operation and the ore haul vehicle, and part of the data becomes information for the maintenance sector which it monitors the operating conditions of various systems. One of the systems deserving attention is the suspension system, responsible for keeping the vehicle running and within a certain vibration condition to keep the asset operational and productive. Thus, this work aims to develop a digital twin-assisted system to evaluate the harmonic response of the vehicle’s body. Two representations were created based on equations of motion that modeled the oscillatory behavior of a mass-damper system. One of the representations indicates a quarter of the ore transport truck’s hydraulic system in a healthy state, called a virtual
Rosa, Leonardo OlimpioBranco, César Tadeu Nasser Medeiros
In the global scenario marked by the increasing environmental awareness and the necessity on reducing pollutant emission to achieve the decarbonization goals, action plans are being proposed by policy makers to reduce the impact of the climate change, mainly affecting the sectors that most contribute to CO2 emissions such as transportation and power generation. In this sense, by virtue of the National Energy Plan 2050, the Brazilian market will undergo the decommissioning of thermal power plants fueled by diesel and heavy fuel oil (HFO) by 2030, compromising about 6.7 GW of power capacity according to the Brazilian Electricity Regulatory Agency (ANEEL) database. An alternative to the scrapping of these engine power plants is their conversion to operate with fuels with a lower carbon footprint, such as the natural gas. This work, therefore, aims to numerically assess the conversion feasibility of a HFO large bore four-stroke turbocharged engine to operate with natural gas by means of a
Gonçalves, Vinícius FernandezZabeu, Clayton BarcelosAntolini, JácsonSalvador, RobertoAlmeida, RogérioValiati, Allan SoaresFilho, Guenther Carlos Krieger
The objective of this study is to investigate the root cause of cracks detected in the Turbocharger bracket belonging to the engine Mercedes-Benz OM471 (Power: 390kW, Torque: 2600Nm) from Vehicle Truck Mercedes-Benz Actros 2651LS 6x4 Euro V. The investigation started with the instrumentation of every related component (besides the bracket itself, the charge air pipe, the exhaust pipe and also the crankcase for reference) in order to perform a vibration measurement. The necessary equipment to execute this procedure, included accelerometers, temperature sensors, strain gages and an inductive engine speed sensor. All data had to be acquired directly from real application conditions in vehicle, maximum load of 74 ton in a previously defined mountain road track, due to the impossibility to generate similar results in comparison to the ones detected on road through bench tests (or any other in-door experiment). The bracket position is located on the right side of a diesel combustion engine
Feijó, Igor SommerfeldGonçalves, Carlos Aurélio Bustamante
Recognizing the significant challenges inherent in the analysis of periodic gas flow through reciprocating engines, one can easily appreciate the value of studying the steady flow through cylinder heads, manifolds, and exhaust systems. In these studies, flow benches are the cornerstone of the experimental apparatus needed to validate theoretical results or to perform purely experimental analysis. The Metal-Mechanics Department of IFSC owns a SuperFlow model SF-110 flow bench that has suffered some in house maintenance and received electronic sensors to allow computerized data acquisition. As the essential original sensors in this flow bench were liquid column manometer (for pressure difference across the test subject) and micromanometer (for pressure difference across the orifice plate used to measure the flow), the essential new sensors are electronic differential pressure sensors (installed in parallel with the original ones). In recent decades, however, the use of a mass air flow
Vandresen, MarceloSantos, Luciano Amaury
During accelerations and decelerations of a race car whose engine has a wet sump, the forces generated by the vehicle’s motion cause the engine oil to vigorously shift towards the walls of the oil pan and crankcase, contributing to the phenomenon known as ‘sloshing.’ This phenomenon often leads to fluctuations in oil pressure, resulting in oil pressure surge, when the oil is pushed away from the pump pickup point. Via the logged data, the Formula UFSM FSAE Team had witnessed a recurrent lack of oil pressure in the race track during the 2023 Brazilian FSAE competition. In the AutoCross Event, the recurrence of this problem was 80% of the right corners on lateral accelerations between 0.80G and 1.30G. The average oil pressure in this condition was 0.80 bar, even reaching 0.10 bar above 5000 RPM. Therefore, it was necessary to develop a new set of baffles for the oil pan, capable of minimizing the effects of sloshing and, consequently, the oil surge. As a method of research, a test bench
Zimmermann, Natalia DiovanaJunior, Luiz Alfredo CoelhoMartins, MarioHausen, Roberto
As a part of an automobile suspension structure, fatigue durability performance of the automotive stabilizer bar linkage is crucial to the safety and reliability of the suspension system. In this study, the modeling and simulation analysis methods of the stabilizer bar linkage were described in detail, especially for the welded positions between the connecting rod and the spherical shells (or sleeves). Based on the equivalent structural stress method and the theory of critical distances, damage values of welded positions in the stabilizer bar linkage were solved. For the spherical shell end, the simulation reproduced the bench test; and for the sleeve end, the analysis approach was determined by comparing in several different modeling ways. Mooney-Rivlin model was adopted to fit the constitutive relationship of rubber material in the bushing. The above methods were applied to predict the fatigue durability performance of the stabilizer bar linkage product, and the effectiveness was
Wang, XuHan, ChaoDeng, Jianjiao
As regulations become more stringent, engine manufacturers are adopting innovative technologies to reduce emissions while maintaining durability and reliability. One approach involves optimizing air handling systems. Eaton developed a 48 V electric exhaust gas recirculation pump (EGRP) to reduce NOx and CO2 emissions while improving fuel efficiency when paired with a high-efficiency turbocharger. This study integrates an electric EGRP and a high-efficiency turbocharger onto a 13.6L John Deere off-road diesel engine to evaluate the impact on fuel efficiency and NOx emissions across various drive cycles including the nonroad transient cycle (NRTC), the low load application cycle (LLAC), the constant speed–load acceptance (CSLA) test, and the ramped modal cycle (RMC). The study highlights the benefits and limitations of the prototype EGRP on an off-road engine. Since the setup did not include aftertreatment systems, engine-out emissions were analyzed. Experiments were conducted at
Willoughby, AudreyAdekanbi, MichaelKakani, RaghavAhmad, Zar NigarShaver, GregHolloway, EricHaaland, EricEvers, MatthewLoesch, AdamMcClurg, JosiahBagal, NileshMcCarthy, JamesCoates, Michael
This study examines performance metrics and emission profiles of Kirloskar TV1 CI engine fuelled with blend containing waste transformer oil (WTO) biodiesel (40%), n-Heptane (10%), and diesel (50%) by volume (referred to as WTO40H10D50), with additional 10 lpm of hydrogen induction in the intake manifold. Effects of varied injection of fuel timing (19°, 21°, and 23°bTDC) and injection pressure (170, 210, and 240 bar) of WTO40H10D50 on diesel engine were analyzed at 100% engine loading condition. The findings indicate that an injection timing of 23°bTDC and an IP of 240 bar yield the highest BTE and lowest BSEC, suggesting optimal energy conversion efficiency. The influence of inducted H2 resulted in the lowest smoke opacity and HC emissions, demonstrating more complete and cleaner combustion. The results indicate at 23° bTDC of injection timing and 240 bar injection pressure produced best overall performance, with highest brake thermal efficiency and the lowest brake specific energy
Veeraraghavan, SakthimuruganPalani, KumaranDe Poures, Melvin VictorMadhu, S.
This study investigates the influence of Silica-Diamond-Like Carbon (Si-DLC) coated pistons on performance metrics of diesel engine fuelled with various blends of Cassia Fistula biodiesel (CFBD10, CFBD20, CFBD30, and CFBD40). The primary focus is on key performance metrics, including Brake Thermal Efficiency (BTE), Brake Specific Energy Consumption (BSEC), and Exhaust Gas Temperature (EGT). The results demonstrated improvement in BTE and EGT, alongside a reduction in BSEC across all biodiesel blends compared to conventional diesel. Specifically, at full engine load, CFBD10 exhibited a BTE of 33.41%, which is 3.17% higher than neat diesel in the stock engine. At part load and no-load scenarios, improvements of 2% and 0.51% over neat diesel were recorded. During no-load conditions, the BSEC for CFBD10 was measured at 9.901 MJ.kW-hr, 0.738 MJ.kW-hr lower than that of neat diesel. Further increases in Cassia fistula blends resulted in higher BSEC values due to lower calorific content
Veeraraghavan, SakthimuruganDe Poures, Melvin VictorMadhu, S.Palani, Kumaran
SAE Formula Student Car Organization mandates the installation of a 20mm diameter restrictor between the throttle body and the engine inlet. The primary objective of this restrictor is to regulate and reduce the mass flow of air into the engine inlet. To achieve this, a venture nozzle has been selected as the ideal component, to decrease air pressure while simultaneously increasing velocity within the intake manifold. This research project focuses on optimizing the restrictor by strategically adjusting the convergent and diverging angles. To enhance the restrictor's efficiency, a comprehensive Computational Fluid Dynamics (CFD) analysis was conducted, exploring a wide range of convergent angles from 12° to 24° and divergent angles spanning from 4° to 8°. The analysis was performed using CFD Fluent within the ANSYS Workbench platform. Following an extensive series of CFD simulations, the optimal angle combination was found to be a converging angle of 20° combined with a divergent angle
Sathishkumar, A.Soundararajan, R.Ram Kumar, S. K.Mahi Kaarthik, G.Raj Vigneshwar, R.Feroz Ali, L.
The larger domain of surface texture geometry and other input variables related to engine operation, i.e., elevated temperature, has remained to be studied for finding suitable surface texture for real-time engine operations. In previous efforts to find suitable surface texture geometry and technique, the tribological performance of the piston material (Al4032) with dimples of varying diameters (90 to 240 μm) was evaluated under mixed and starved lubrication conditions in a pin-on-disk configuration. The disc was textured using a ball nose end mill cutter via conventional micromachining techniques. The area density and aspect ratio (depth to diameter) of the dimples were kept constant at 10% and 1/6, respectively. SAE 20W-40 oil was used as a lubricant with three separate drop volumes. The experiments were conducted in oscillating motion at temperatures of 50, 100 and 150°C. Conventional micromachining achieved improved dimensional precision and minimized thermal damage. Textured
Sahu, Vikas KumarShukla, Pravesh ChandraGangopadhyay, Soumya
Cooling system for an IC engine, consisting of the Water pump (WP), Radiator and Fan, plays an important role in maintaining thermal efficiency of the engine and protects the engine from overheating. Based on the vehicle application requirement, Fan will be mounted directly either on Crankshaft or WP pulley. But wherever increase in Fan speed ratio are in demand, it is preferred to mount the Fan on WP pulley. So it important to understand the WP housing structural strength with respect to vibration loads contributed from Radiator Fan assembly. This paper presents investigation of Failure of WP Housing during engine validation at engine test bed with Electronic Viscous Fan, based on the different operating conditions of the engine and fan as per the validation cycle. While the accessories are loading and the corresponding stresses are high when the fan is engaged. But in the current case, the failure of WP housing happened only during Fan clutch disengaged condition. Experimental
R, Mahesh Bharathi
This paper analyses the causes of thrust bearing failure during engine durability evaluations in naturally aspirated engine. The primary objective is to provide an experimental methodology for engineers and researchers investigating such failures. By employing Fault Tree Analysis (FTA), the study identifies potential sources of failure and recommends measures to minimize or eliminate them. The research focuses on a case study involving the observation of thrust bearing chip-off after engine durability test. Root cause analysis was conducted using vibration, rotational fluctuation, and dynamic crank axial measurements. Time domain data analysis was performed to establish the failure mechanism, and the impact of the testing setup was discussed based on this mechanism. Additionally, the study considers the effect of subsystems, such as the engine dynamometer, transmission, and propeller shaft, on thrust bearing failure. The findings from this study aim to enhance the understanding of
Kumar, AshokP, PrasathChoubisa, ManasSau, Sanjoy
The modern-day development in the field of mobility demands the development of advanced engineering materials for various engineering applications. Composite materials play a pivotal role in the advancement of mobility by achieving overall weight reduction and thereby contributing to the sustainability of the environment. Metal matrix composites has played a crucial role over the last few decades in the automotive industry replacing the conventional metal in achieving a better strength to weight ratio. Metal matrix composites can be a combination of a metal and a ceramic combined at a macroscopic level to achieve better mechanical and tribological properties at a reduced weight to strength ratio. Aluminium being one of the largest metals widely used in automobiles, are gradually being replaced with Aluminium metal matrix composites. Aluminium – silicon carbide composite is a key interest among the researchers due to the attractive mechanical and tribological properties that enhance the
Valsan, Ashray
This study investigated the contact pressure distribution of three combustion seal designs for fuel injectors using both experimental techniques and finite element analysis (FEA). The designs tested included the baseline seal (Design #1), a conical seal (Design #2), and the current production seal (Design #3). In phase 1, a 2D axisymmetric FEA was conducted under worst-case torque conditions (67.8 Nm) to simulate contact pressure, with an axial load of 10 kN and combustion pressure of 21.3 MPa applied to the injector assembly. Phase 2 employed Fuji films to measure the pressure distribution at higher torques (89.5 and 115.2 Nm) in a more realistic scenario, incorporating challenges such as misalignment and eccentric loading. During this phase, Fuji film shearing was a significant challenge, complicating the accurate assessment of pressure profiles. Design #1 failed to maintain the minimum threshold contact pressure of 70 MPa over a 1 mm length, leading to potential leakage. Design #2
Kaliyanda, Aneesh
ABSTRACT Cylinder Pressure Monitoring (AVL CYPRESS™) is a technology which provides closed-loop feedback to enable real-time control of combustion in a compression ignition engine. This makes it possible to adapt to the fuel ignition quality and energy density by adjusting the main injection quantity and the placement of the injection events. The engine control system can thus detect fuel quality and adapt the combustion phasing quickly and robustly – and without any prior knowledge of fuel properties. By using a cylinder pressure sensor(s), the engine controller will be able to map the development of the apparent rate of heat release (ARHR) and the mass fuel burn curve - which provides good thermal efficiency correlation. The cylinder pressure map detects the combustion event and the feedback controller adjusts the start of injection to maintain the combustion event at the desired crank position. The cylinder pressure sensor allows for accurate measurement of the power produced. By
Johnson, GustavHunter, Gary
ABSTRACT 3D printing is a rapidly evolving technique for alternative piston manufacturing that offers the ability to realize complex combustion bowl geometry, robust structure and advanced cooling channel geometries while delivering precise tolerance and mass control. IAV has designed, analyzed, optimized and produced 3D printed pistons for heavy-duty diesel engines. The key features include an innovative form of combustion bowl, 300 bar peak cylinder pressure capability and advanced cooling channels in a mass neutral to less capable design. During 2018, these pistons will undergo fired engine testing
Dolan, RobertBudde, RogerSchramm, ChristianRezaei, Reza
ABSTRACT The next generation of military vehicles will require new and improved power systems. As fuel prices continue to rise and as power draws become greater on tactical wheeled vehicles, the performance and efficiency of the power system becomes more important. Up to 40% of vehicular traffic in combat theater is dedicated to fuel and water logistics. Reduction in fuel consumption will result in less traffic and reduced exposure to IED’s as well as gains in cost efficiency. Advances in powertrain and vehicle systems are required to achieve these gains. Hybrid propulsion systems have been proven in passenger automobiles as well as some commercial applications. This technology enables fuel economy improvements upwards of 25%. Hybrid systems can also provide export power and silent watch capability for military vehicles. Duty cycle and environmental demands are more severe in military applications and current energy storage devices are not robust. Several hybrid military platforms have
Milner, DavidSmith, WilfordAlbers, Ken
ABSTRACT The majority of commercial off the shelf (COTS) diesel engines rely on EGR to meet increasingly stringent emissions standards, but these EGR systems would be susceptible to corrosion and damage if JP-8 were used as a fuel due to its high sulfur content. Starting with a Cummins 2007 ISL 8.9L production engine, this program demonstrates the modifications necessary to remove EGR and operate on JP-8 fuel with a goal of demonstrating 48% brake thermal efficiency (BTE) at an emissions level consistent with 1998 EPA standards. The effects of injector cup flow, improved turbo match, increased compression ratio with revised piston bowl geometry, increased cylinder pressure, revised intake manifold for improved breathing, and piston, ring and liner designs to reduce friction are all investigated. Testing focused on a single operating point, full load at 1600 RPM. This engine uses a variable geometry turbo and high pressure common rail fuel system, allowing control over air fuel ratio
Lutz, TimModiyani, Rajani
ABSTRACT ACT's non-catalytic, sulfur-tolerant “Swiss-roll” reforming technology is an effective way to provide the required reformate composition for the Army’s SOFC system. This technology will enable DoD to implement efficient and low acoustic signature Solid Oxide Fuel Cell (SOFC) system in the field and satisfy the Single Fuel Policy. While the high sulfur content of JP-8 and coke formation pose significant challenges for catalytic-based reforming systems, the thermal partial oxidation based reformer is comparatively less complex, highly compact, lightweight and requires minimal power consumption. These advantages allow for a fuel cell fed with JP-8 be implemented in a transportable system, such as ground vehicle, with low acoustic signature for the US Army
Chen, Chien-HuaPearlman, HowardZelinsky, RyanCrawmer, JoelRichard, BradleyRonney, Paul
Abstract Line2Line’s patented abradable powder surface coatings are a mechanism by which clearance between mating components is reduced, and the tribological properties of the interacting surfaces can be improved. The following discussion presents the modeling efforts targeting the numerical analysis of abradable powder piston skirt coatings. This study employs the Cylinder-Kit Analysis System for Engines (CASE) by Mid-Michigan Research to model the performance enhancements offered by abradable powder coatings as applied to piston skirts. Two piston models were generated for the purposes of this analysis, one with the post-run stock reference geometry and coating, as supplied by the manufacturer, and the second having the Line2Line post-run coated geometry. The pistons modeled had been installed within two separate Cummins R2.8 L turbo diesel engines, both of which were subject to several hours of runtime. The primary finding of the current study is that the Line2Line abradable powder
Nicklowitz, DanielSchock, HaroldSuman, AndyLowe, JimWood, Ai LeGrande
ABSTRACT Propulsion systems for military applications, especially for ground combat vehicles, operate in harsh environments and must fulfill a long list of challenging technical requirements. High power density, fuel efficiency, multi-fuel capability, reliability and serviceability are only a few of the top level requirements that cascade down to many sub-system requirements. As part of the Combat Vehicle Prototyping (CVP) program, the US Military is focusing on opposed piston engine technology to meet the requirements for the Advanced Combat Engine (ACE). Globally, opposed piston engines have no considerable presence in commercial applications and have been mostly replaced for military applications. This paper reviews the opportunities and challenges with opposed piston engine technology and introduces an advanced high-performance 4-stroke engine solution as alternative for the ACE
Franke, MichaelKoehler, ErikTomazic, Dean
ABSTRACT This paper discusses inherent advantages and additional design changes that can be made to a single crankshaft opposed piston engine (SCOPE) in order to satisfy military engine heat rejection-to-power requirements of 0.45. The paper starts off with a discussion of the currently demonstrated heat rejection to power levels being obtained with the commercial version of the SCOPE configuration. Here, it is seen that heat rejection-to-power ratios are approximately 0.69. Tests are ongoing and this value is considered preliminary in nature. Analytical results are then presented that decompose where the heat is being generated - for the intake air system, the coolant system, and also the oil lubrication system. The model includes consideration of heat generated from the engines turbochargers, cylinders, pistons, and gear train. The model is anchored to measurements made with a commercial version of the SCOPE engine. Engine heat rejection results for this baseline configuration
Kacynski, KenJohnson, S. ArnieHuo, MingYancone, J.Katech, Chris Meszaros
ABSTRACT VanDyne SuperTurbo Inc. has recently completed Phase I of an Army SBIR project entitled “Diesel Waste Heat Recovery Utilizing a SuperTurbocharger”. The project focused on modeling a SuperTurbocharger for a specific Army application and evaluating the potential benefits from a single device capable of supercharging, turbocharging and turbocompounding. The modeling effort resulted in predicted efficiency gains from both air flow management and mechanical waste heat recovery. Additionally, the modeling program revealed additional engine power available that was inaccessible with the engine’s current turbocharged configuration. This paper will cover the fundamentals of the technology, the Phase I engine modeling results and the path forward for the Phase II prototype testing project
VanDyne, EdWaldron, Thomas
ABSTRACT Modern medium and heavy duty Commercial Off The Shelf (COTS) diesel engines take advantage of state-of-the-art technologies to deliver excellent performance while meeting the most stringent emissions legislation. While some of these technologies offer significant advantages in terms of engine efficiency, performance and weight versus traditional military engines, others are driven purely by the need to meet emissions standards. In order to successfully adapt these COTS engines for military use and fuel (JP-8), the emissions-only systems must be removed and the engine recalibrated for maximum efficiency. The downsized, turbocharged engine would enable a simultaneous improvement in engine weight, performance and efficiency in one of the DoD’s largest fleet of vehicles - High Mobility Multipurpose Wheeled Vehicle (HMMWV), when compared to the current configuration. This paper will illustrate how a modern diesel engine was quickly developed from COTS to military-ready
Johnson, Gustav
ABSTRACT The need for current and future military vehicles to include more powerful and efficient powertrains is critical to both improving operational performance and reducing logistical burden. VanDyne SuperTurbo Inc. is working jointly with TARDEC and OEM partners to develop and field a revolutionary technology that simultaneously increases available engine power and reduces overall fuel consumption. The ability to incorporate efficient supercharging will allow vehicles to accelerate faster in combat situations and accept a heavier load. The ability to mechanically recover waste heat energy will allow vehicles to improve their operational range and reduce the Class III supply chain. SuperTurbo technology additionally reduces visible soot emissions and is transferable to gensets and other equipment. The end result of fielding this kind of capability will be a force protection multiplier that equips the warfighter with better performing systems
Waldron, ThomasVanDyne, EdBrown, Jared
ABSTRACT Additive/Abradable Powder Coatings (AAPC’s) are field proven, thick, solid film graphite coatings that wear in to the ideal functional geometry of mechanical components. Lubed or dry, devices lap in and run with minimized clearance and friction for highest efficiency, quietest operation, and longest life in sandy environments. AAPC’s will improve military readiness, reduce sustainment costs, and cut components logistics and fuel consumption. Processing is easy, robust and effective on new and used components in prototyping, production and remanufacturing. Worn components can be restored in theater to achieve durable, ‘better than new’ performance levels. Applications include turbos, IC pistons, lube pumps, hydraulics, roots blowers, screw compressors, refrigerant compressors, lip seal seats, and others. This paper will focus on the AAPC benefits observed on pistons and turbo compressor housings
Suman, Andrew
ABSTRACT A sudden increase in microgrid electrical power consumption requires the fast supply of energy from different generating sources to guarantee microgrid voltage stability. This paper presents the results of simulations investigating the integration of an electric supercharger into a Heavy Duty Diesel (HDD) genset connected to a microgrid for reducing engine speed droop in response to an abrupt power demand requested from the grid. First, a mean value model for the 13 L HDD engine is used to study the response of the baseline turbocharged engine during a fast load increase at low engine speed. The limited air mass in the cylinder during the transient results in engine lugging and ultimately engine stall. Then, an electrical supercharger is integrated before the turbocharger compressor to increase the engine air charge. During steady state operation, the simulation results indicate that the supercharger is able to increase the air-charge by approximately 50% over the lower half
Salehi, RasoulMartz, JasonStefanopoulou, AnnaRizzo, DeniseMcGrew, DeanHansen, Taylor
ABSTRACT This paper details the exploration of oil jet piston cooling phenomenon with a focus on heat transfer from the diesel engine piston to the oil. Several numerical methods based on computational fluid dynamics (CFD) and conjugate heat transfer (CHT) were developed to resolve key aspects of piston oil cooling. These methods aim to establish and characterize the flow and heat transfer regimes that are inherent to the piston gallery cooling system, and to assist in quantifying the piston heat transfer and establish its dependence on a number of parameters related to the engine layout and performance, the oil cooling system, and the cooling gallery contained within the piston. Telemetry experimental data from a single-cylinder diesel engine was used to better understand the piston cooling system and to develop and validate modeling and simulation approaches. The combined findings offer a foundation for further study of oil jet piston cooling. Citation: A. Grunin. V. Korivi, “Oil
Grunin, ArkadyKorivi, Vamshi
ABSTRACT The latest advancements in common rail fuel injection system, material science, engine control strategies, and manufacturing technologies have challenged and allowed engine designers to create a high power density, fuel efficient, reliable, and environmental friendly multi-fuel engine. To increase power density a novel high-speed 2-stroke turbocharged compression ignition engine will feed the pressurized air directly into the combustion chamber without going through the crankcase. Thus, only pressurized clean air will be used for combustion and oil consumption will be dramatically reduced. To further improve volumetric efficiency and reduce emissions, a computer controlled dynamic variable valve timing system can be incorporated such that the optimum amount of pressurized air will be available for combustion at various loads and conditions. Combustion efficiency at different loads can be optimized by adjusting the compression ratio dynamically through computer control. By
Chue, Stephen
ABSTRACT This paper provides a brief historical look at opposed-piston, two-stroke (OP2S) engines and their use in military applications. It also highlights the engine’s fundamental architectural advantages. In addition, the paper introduces the Achates Power opposed-piston engine, providing detailed, measured results of its power density, thermal efficiency and low heat rejection. Furthermore, the paper includes an overview of the fundamental challenges of OP2S engines, along with a discussion of how Achates Power has addressed these issues. Finally, the paper demonstrates that the operating characteristics of the Achates Power opposed-piston engine allow for optimizing the power density of the entire vehicle propulsion system as defined by Charles Raffa, Ernest Schwarz and John Tasdemir [1
Fromm, LaurenceHerold, RandyKoszewnik, JohnRegner, Gerhard
A reactivity-controlled compression ignition (RCCI) engine offers ultralow soot and nitrogen oxide (NOx) emission in addition to higher thermal efficiency than diesel or compression ignition (CI) engines. However, the higher emissions of unburned hydrocarbons (HC) and carbon monoxide (CO) from RCCI engines pose a significant challenge that hinders their adoption in the future automotive sector. Additionally, HC includes several hydrocarbons that harm human health and the environment. This study aims to minimize HC and CO formation and emissions by implementing different injection strategies, including adjustments to spray angle configuration, injection timing, and fuel premixing ratio. Additionally, the study examines how different injection strategies affect the spatial and temporal distribution of HC and CO inside the combustion chamber. To achieve this objective, a numerical investigation is conducted on a single-cylinder diesel engine modified to operate in RCCI mode, utilizing a
Yadav, Neeraj KumarChandel, Amit SinghMaurya, Rakesh KumarPadhee, Srikant Sekhar
The use of carbon-free fuels, such as ammonia or hydrogen, or at least carbon neutral fuels, such as green methane or methanol is one of the most important paths in the development of low-carbon internal combustion engines (ICE). Especially for large, heavy-duty engines, this is a promising route, as replacing them with battery electric or fuel cell drives poses even greater challenges, at least for the time being. For some applications or areas of the world, small ICEs for trucks, passenger cars or off-road vehicles, operated with alternative fuels will still remain the means of choice. One of the biggest challenges in the development of hydrogen combustion engines is achieving high compression ratios and mean effective pressures due to combustion anomalies, caused by the low ignition delay and broad flammability limit of hydrogen. Oil droplets are considered to be one of the main triggers for pre-ignition and knocking. This paper will give a brief introduction, showing the results of
Rossegger, BernhardGrabner, PeterGschiel, KevinVareka, Martin
Hydrogen as a chemical energy carrier is considered as one of the most promising options to achieve effective decarbonization of the transportation sector, due to its carbon-free chemical composition. This is particularly true for applications that rely on internal combustion engines (ICEs), although much research is still needed to achieve stable, reliable, and safe operations of the engine. To this purpose, direct injection (DI) of gaseous hydrogen during the compression stroke offers great potential to avoid backfire and largely reduce preignition issues, as opposed to port-fuel injection. Recently, much research has been dedicated, both experimentally and numerically, to understanding the physics and chemistry connected with hydrogen’s mixing and combustion processes in ICEs. This work presents a computational fluid dynamics (CFD) study of the hydrogen DI process in an optical engine operating at relatively low tumble conditions. Gaseous hydrogen pressurized at 86 bar is introduced
Torelli, RobertoWu, BifenPark, Ji-WoongPei, Yuanjiang
The development of new fuels for internal combustion engines (ICE) requires further technical support by understanding the pollutant formation mechanism in various phases of combustion so that emissions can be minimised. This research will therefore utilize a bespoke in-cylinder sampling system to analyse the precursors of Polycyclic Aromatic Hydrocarbons (PAHs) and Particulate Matter (PM) during bio-derived lactone combustion in a single-cylinder diesel engine. The sampling system was composed of a poppet-type in-cylinder sampling valve that displaced one of the engine’s intake valves and protruded into the combustion chamber beyond the flame quenching layer, and a Gas Chromatography Flame Ionization Detector (GC-FID) that analysed the samples. The sampling valve was electromagnetically actuated, and its operation was referenced to the engine crank shaft encoder allowing the valve to open at any crank angle degree (CAD) within a timing resolution of 0.2 CAD. Lactones are oxygenated
Han, YanlinHellier, PaulWu, JinchengLadommatos, Nicos
Recuperated low-pressure-ratio split-cycle engines represent a promising engine configuration for applications like transportation and stand-alone power generation by offering a potential efficiency as high as 60%. However, it can be challenging to achieve the stringent NOx emission standard, such as Euro 6 limit of 0.4 gNOx/kWh, due to the exhaust cylinder high intake temperature. This paper presents experimental investigation of hydrogen-air combustion NOx emissions for such engines for the first time. Experiments are carried out using a simplified constant-volume combustion chamber with glow-plug ignition. Two fuel injection techniques are performed: direct injection and injection via a novel convergent-divergent injector. For the direct injection scenario, NOx levels are unsatisfactory with respect to the Euro 6 standards over a range of operating temperatures from 200 °C to 550 °C. Recorded NOx levels can reach twice the permissible limit which necessitates the implementation of
Eldakamawy, Mohamed HossamPicard, Mathieu
For turbocharged engine design, manufacturer-provided turbocharger maps are typically used in simulation analysis to understand key engine performance metrics. Each data point in the turbocharger map is generated by physically testing the hardware or through CFD analysis—both of which are time-consuming and expensive. As such, only a modest set of data can be generated, and each data map must be interpolated and extrapolated to create a smooth surface, which can then be used for engine simulation analysis. In this article, five different machine learning algorithms are described and compared to experimental data for the prediction of Cummins Turbo Technologies (CTT) fixed geometry turbines within and outside of the experimental data range. The results were validated against xxx-provided test data. The results demonstrate that the Bayesian neural networks performed the best, realizing a 0.5%–1% error band. In addition, it is extrapolatable when suitable manually created extra data
Supe, ShreyasNatarajan, BharathShaver, Greg
Turbocharger design involves adjustment of various geometric parameters to improve the performance and suit mechanical constraints, depending on the application-specific requirements. In designing the turbine stage, these parameters are optimized to maximize durability and efficiencies at the required operating points. For a heavy-duty class eight truck, “road load” and “rated power” are generally considered the two most important operating points. The objective of this article is to improve the efficiencies of these two operating points. The common challenge in the development of a turbine wheel design is the large number and interdependence of parameters to optimize. For example, increasing the blade thickness improves structural strength but reduces the mass flow capacity, thus influencing its performance. It is general practice to optimize the wheel geometry using iterative CFD analysis. However, running simulations for every single change in geometry involves significant
Wichlinski, JosephGonser, LukasNaik, PavanTaylor, Alexander H.Al-Hasan, Nisar S.
This SAE Aerospace Standard (AS) covers combustion heaters and accessories used in, but not limited to, the following applications: a Cabin heating (all occupied regions and windshield heating) b Wing and empennage anti-icing c Engine and accessory heating (when heater is installed as part of the aircraft) d Aircraft deicing
AC-9 Aircraft Environmental Systems Committee
During a recent Bosch tech showcase, we spoke with Joe Dear, engineering manager for electric propulsion systems at Linamar. The Guelph, Ontario-based parts manufacturer is no stranger to building unsung components for the auto industry, including gears, camshafts, connecting rods, and cylinder heads. The Linamar team was demonstrating a modified Ram 2500, a collaboration between Bosch and Linamar, that was outfitted with a prototype electric powertrain and new e-axles: a rigid axle on the rear (with a Bosch motor and inverter) and a steering axle up front
Blanco, Sebastian
Airplane turbines and rocket engines are very powerful, hot and noisy and yet in need of extremely sensitive measurement technology. And they have another thing in common: They are most efficient when they run on a constant and even flame. Specialized measurement technology helps aerospace engineers improve combustion chambers and fuel injectors. In Switzerland, two ambitious student organizations have been using iterative pressure measurements to develop and build a significantly more efficient next generation of rocket engines
Reducing vehicle weight is a key task for automotive engineers to meet future emission, fuel consumption, and performance requirements. Weight reduction of cylinder head and crankcase can make a decisive contribution to achieving these objectives, as they are among the heaviest components of a passenger car powertrain. Modern passenger car cylinder heads and crankcases have greatly been optimized in terms of cost and weight in all-aluminum design using the latest conventional production techniques. However, it is becoming apparent that further significant weight reduction cannot be expected, as processes such as casting have reached their limits for further lightweighting due to manufacturing restrictions. Here, recent developments in the additive manufacturing (AM) of metallic structures is offering a new degree of freedom. As part of the government-funded research project LeiMot [Lightweight Engine (Eng.)] borderline lightweight design potential of a passenger car cylinder head with
Kayacan, CanPischinger, StefanAhlborn, KlausBültmann, Jan
Proton exchange membrane (PEM) fuel cells are one potential green energy option for fuel cells, which are becoming more popular in the energy production industry. Despite the fact that it continues to draw a lot of interest, many obstacles, such as enhancing performance, boosting durability and reducing cost are impeding the fuel cells commercialization. Air/hydrogen feed has an impact on the fuel cell performance; as a result, the cathode side of the fuel cell supply manifold pressure must be regulated. Substantial power is used when operating at maximum load, and fuel cells may experience oxygen starvation due to inadequate air. Maintaining a quick and adequate air concentration in the fuel cell cathode is essential to avoiding oxygen starvation and maximizing durability. In this paper, to solve the issues of oxygen starvation in a PEM fuel cell, various fractional order control strategies are developed, and comparative analysis is done to maintain the supply manifold pressure based
A, AdithyaShaik, AmjadCHIKATI, RAMBABU
The impacts of injection pressure with a Gaussian-shaped ribbed piston bowl design for energy-assisted compression-ignition (EACI) combustion were investigated in an optically accessible engine. Three injection pressures (600, 800, and 1000 bar) were investigated for three potential first injection timings corresponding to injection timings for injection dwells of 1.5, 2.0, and 2.5 ms of a fixed second injection timing of -5.0 CAD. Reliable positioning of the hot combusted gases from the first injection near the injector tip enables mixing-controlled combustion of the second injection. Results demonstrated the EACI capabilities of pairing high injection pressures with the Gaussian-shaped ribbed piston bowl. At higher injection pressures, the redirection of fuel vapors from the in-line fuel jet back toward the ignition assistant (IA) increased the residence time the fuel mixture was exposed to the hot zone from the ignition assistant, reducing the possibility of misfires. Results also
Amezcua, Eri R.Stafford, Jacob M.Rothamer, David A.Kim, Kenneth S.Kweon, Chol-bum M.
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