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Technical Paper

Knockdown Factor Estimation of Stiffened Cylinders under Combined Loads - A Numerical Study

2024-06-01
2024-26-0417
Airframe section of rockets, missiles and launch vehicles are typically cylindrical in shape. The cylindrical shell is subjected to high axial load and an external pressure during its operation. The design of cylinders subjected to such loads is generally found to be critical in buckling. To minimize the weight of cylinders, it is typically stiffened with rings and stringers on the inner diameter to increase the buckling load factor. Conventionally the buckling load estimated by analytical or numerical means is multiplied by an empirical factor generally called Knockdown factor (kdf) to get the critical buckling load. This factor is considered to account for the variation between theory and experiment and is specified by handbooks or codes. In aerospace industry, NASA SP 8007 is commonly followed and it specifies the kdf as a lower bound fit curve for experimental data .
Technical Paper

Fully Retractable Easy Access Spare Wheel Carrier Mechanism for Commercial Vehicles.

2024-04-09
2024-01-2225
In today's market practise & standard mechanism being provided from OEM, tyre changing mechanism is a tedious job, took long time & much higher efforts in Indian trucking industry harsh environments. Heavy commercial vehicles are fitted with spare wheel carrier that has a rope mechanism to load and unload the spare wheel. The mounting of this system is generally on side of frame/ chassis or within the limits of side member. The invention reduces effort and time required to remove spare tyre. The invention brings the spare wheel to a vertical position where it is easy to remove its bolts and remove it from its mountings. Also, this innovative mechanism is well supported by 3 way actuation system (Air Actuated system, Electric motor driven system or Hydraulic cylinder actuated mechanisms), which reduced human efforts and gives benefit to drivers in terms of comfort.
Technical Paper

New Solution for Material Damage Characterization of CFRP Laminate with Filament Winding Structure Using a Hexagonal-Shaped Mandrel

2024-04-09
2024-01-2884
CFRP manufactured by a filament winding process has a unique laminate structure. So far, a material damage model applied to design CFRP component manufactured by FW process was identified using a material property of a CFRP flat plate laminated unidirectionally with predetermined angle. However, from these material properties the effect of filament winding structure cannot be evaluated nor can be introduced to the material model. In this study, a newly hexagonal shaped mandrel with flat parts on the cylinder and dome region of the high-pressure vessel was devised and a procedure of a flat plate laminate with filament winding structure was proposed. Filament winding structure on a flat surface by this method matched well with that of the curved surface simulated by ComposCad. In addition, the FEM simulation result of meso-scale laminate coupon model using material damage model obtained from material property of coupon matched well with the experimental result. 
Technical Paper

A Three-Way Catalyst model for a bio-methane Heavy-Duty engine: characterization at different lambda

2024-04-09
2024-01-2084
Given the spread of natural gas engines in low-term toward decarbonization and the growing interest in gaseous mixtures as well as the use of hydrogen in Heavy-Duty (HD) engines, appropriate strategies are needed to maximize thermal efficiency and achieve near-zero emissions from these propulsor systems. In this context, some phenomena related to real-world driving operations, such as engine cut-off or misfire, can lead to inadequate control of the Air-to-Fuel ratio, key factor for Three-Way Catalyst (TWC) efficiency. Goal of the present research activity is to investigate the performance of a bio-methane-fueled HD engine and its aftertreatment system, consisting of a Three-Way Catalyst, at different Air-to-Fuel ratio. An experimental test bench characterization, in different operating conditions of the engine workplan, was carried out to evaluate the catalyst reactivity to a defined pattern of the Air-to-Fuel ratio.
Technical Paper

Virtual Chip Test and Washer Simulation for Machining Chip Cleanliness Management Using Particle-Based CFD

2024-04-09
2024-01-2730
Metal cutting/machining is a widely used manufacturing process for producing high-precision parts at a low cost and with high throughput. In the automotive industry, common engine components such as cylinder heads or cylinder blocks are all manufactured using such processes. Despite its cost benefits, manufacturers often face the problem of machining chips and cutting oil residue remaining on the finished surface after machining operations, and these wastes can be very difficult to clean. While part cleaning/washing equipment suppliers often claim that their washers have superior performance, determining the washing efficiency is challenging without knowledge of chip clogging locations and water jet flow patterns. In this paper, a virtual engineering methodology using particle-based CFD is developed to manage the metal chip cleanliness issue resulting from engine component machining operations. This methodology comprises two simulation methods.
Technical Paper

Numerical Study on the Combustion Characteristics of an Ammonia/Hydrogen Engine with Active Prechamber Ignition

2024-04-09
2024-01-2104
With the implementation of global carbon reduction policies, there has been a growing emphasis on the research of zero-carbon fuels. Both ammonia and hydrogen, as zero-carbon fuels for internal combustion engines, come with their own set of advantages and disadvantages. Jet ignition, known for its high ignition energy and rapid flame propagation velocity, offers a more effective ignition means of combining ammonia and hydrogen than spark ignition for use in the engine. This paper, while maintaining the lambda value of 1, conducted a numerical study to assess the impact of various prechamber structures on the combustion characteristics of an ammonia/hydrogen engine. Firstly, the nozzles angle emerges as a critical parameter in the design of active prechamber structures.
Technical Paper

Combustion analysis of Hydrogen-DDF mode based on OH* chemiluminescence images

2024-04-09
2024-01-2367
Hydrogen-diesel dual-fuel combustion processes were studied in a rapid compression and expansion engine (RCEM). In the experiments, the combustion processes were visualized using an optically accessible RCEM that can simulate a single compression and expansion stroke of a diesel engine. A small amount of diesel was injected as a pilot ignition for the hydrogen, with injection pressures of 40, 80, and 120 MPa using a common rail injection system. The amount of diesel injected was varied as 3, 6, and 13 mm3. The hydrogen-air mixture was introduced into the combustion chamber through the intake valve. The amount of hydrogen was manipulated by varying the total excess air ratio(λtotal) at 3 and 4. The RCEM was operated at a constant speed of 900 rpm, and the in-cylinder pressure and temperature at TDC were set at 5 MPa and 700 K, respectively.
Technical Paper

Low-Cost Open-Source Data Acquisition for High-Speed Cylinder Pressure Measurement with Arduino

2024-04-09
2024-01-2390
In-cylinder pressure measurement is an important tool in internal combustion engine research and development for combustion, cycle performance, and knock analysis in spark-ignition engines. In a typical laboratory setup, a sub crank angle (CA) resolved (typically between 0.1 and 0.5 degree) optical encoder is installed on the engine crankshaft, and a piezoelectric pressure transducer is installed in the engine cylinder. The charge signal produced by the transducer due to changes in cylinder pressure during the engine cycle is converted to voltage by a charge amplifier, and this analog voltage is read by a high-speed data acquisition (DAQ) system at each encoder trigger pulse. The high speed of engine operation and the need to collect hundreds of engine cycles for appropriate cycle-averaging requires significant processor speed and memory, making typical data acquisition systems very expensive.
Technical Paper

Next Generation High Efficiency Boosted Engine Concept

2024-04-09
2024-01-2094
Ford Motor Company, working with FEV North America and Oak Ridge National Laboratory, developed a concept for a next generation of boosted spark ignited engine for application in light-duty on-highway vehicles. Key goals were 23% improved fuel economy and 15% reduced weight compared to a baseline 2016 Model Year Ford 3.5 L Ecoboost engine system in the lead application of a Ford F150. Additional requirements include the use of conventional regular E10 gasoline fuel and conventional exhaust aftertreatment employing 3-way catalyst technology for compliance with U.S. and global pollutant emissions regulations. A modular inline 6-cylinder engine whose technical assumptions include high 14:1 geometric compression ratio, large stroke-to-bore ratio of 1.33, continuously variable intake valve lift and timing, variable geometry turbocharger, active pre-chamber ignition system, cooled low pressure EGR, and innovative active cooling system.
Technical Paper

Study of Dimethyl Ether Fuel Spray Characteristics and Injection Profile

2024-04-09
2024-01-2702
The majority of transportation systems have continued to be powered by the internal combustion engine and fossil fuels. Heavy-duty applications especially are reliant on diesel engines for their high brake efficiency, power density, and robustness. Although engineering developments have advanced engines towards significantly fewer emissions and higher efficiency, the use of fossil-derived diesel as fuel sets a fundamental threshold in the achievable total net carbon reduction. Dimethyl ether can be produced from various renewable feedstocks and has a high chemical reactivity making it suitable for heavy-duty applications, namely compression ignition direct injection engines. Studies of dimethyl ether for engine combustion have shown positive results with an ultra-low propensity to form soot regardless of NOx levels. Further reduction in NOx and soot emission regulations presents a significant challenge to combustion performance.
Technical Paper

Numerical study on the design of a passive prechamber on a heavy-duty hydrogen combustion engine

2024-04-09
2024-01-2112
Lean-burning hydrogen internal combustion engines are potentially a good option for future transportation solutions since they do not emit carbon-dioxide and unburned hydro-carbons, and the emissions of nitric-oxides can be kept low. However, under lean-burn conditions the combustion duration increases and the combustion stability decreases, leading to a reduced thermal efficiency. Turbulent jet ignition (TJI) can be used to extend the lean-burn limit, while decreasing the combustion duration and improving combustion stability. The objective of this paper is to investigate the feasibility of a passive prechamber TJI system on a heavy-duty hydrogen engine under lean-burn conditions using CFD modelling. The studied concept is mono-fuel, port-fuel injected, and spark ignited in the prechamber. The overall design of the prechamber is discussed and the effect of certain design parameters have on the engine performance are studied.
Technical Paper

The New Toyota 2.4L L4 Turbo Engine with 8AT and 1-Motor Hybrid Electric Powertrains for Midsize Pick-up Trucks

2024-04-09
2024-01-2089
It is more and more challenging for internal combustion engines in pick-up trucks which have heavy weight and high drag, to fulfill both strict fuel economy and emission regulations toward the target of “Carbon Neutrality”, while exceeding customer expectations. To overcome these difficult tasks, Toyota has developed the new 2.4L L4 turbocharged gasoline engine which for the first time complies with severe emission regulations such as Tier3 Bin30/LEVIII SULEV30 for body-on-frame midsize pick-up trucks. At the same time, both thermal-efficiency and maximum torque are improved by adopting high-speed combustion to the turbocharged engine based on the TNGA (Toyota New Global Architecture) platform, spray guide combustion by center direct injection in combustion chamber, quick light-off close-coupled three-way catalyst and a quick response turbocharger.
Technical Paper

Effect of in-cylinder flow motion on fuel-air mixture formation in a medium-duty DI-SI H2 engine: an experimentally supported CFD study

2024-04-09
2024-01-2117
The increased utilization of batteries and fuel-cells for powering electric applications, as well as bio- and e-fuels into internal combustion engines are seen as options to lower the carbon footprint of industry and transportation sectors. When high power outputs and fast refuelling are requisites, H2 ICEs may be a relevant choice. Applications include electricity conversion within a genset or mechanical energy in a vehicle. Within this framework, a John Deere 4045 Diesel engine converted to a H2 single-cylinder is studied at relevant operating conditions for the mentioned use cases, which pose high torque and power output requirements. The modified engine integrates a Phinia DI-CHG 10 outward-opening H2 injector instead of the Diesel unit, as well as a spark-plug rather than the standard glow-plug.
Technical Paper

Benchmarking of Neural Netowrk Methodologies for Piston Thermal Model Calibration

2024-04-09
2024-01-2598
During the design phase of engine components, it is important to have accurate model predictions of the temperature field in order to adequately capture temperature-dependent material behavior and thermal gradients that greatly influence the component fatigue life. In pistons, the heat transfer analysis depends on backside heat transfer boundary conditions (BCs), which are difficult to estimate. One method to circumvent this problem is to collect experimental temperature data and calibrate the backside heat transfer BCs in a computer model to this data. Previously, a traditional Bayesian calibration methodology has been successfully applied to calibrate these backside BCs in piston heat transfer models to experimental data. This method leverages the use of Gaussian process surrogate modeling of the computer model and then performing Bayesian inference on the unknown boundary conditions, which can be computationally expensive.
Technical Paper

A Deviation-based Centroid Displacement Method for Combustion Parameters Acquisition

2024-04-09
2024-01-2839
The absence of combustion information continues to be one of the key obstacles to the intelligent development of engines. Currently, the cost of integrating cylinder pressure sensors remains too high, prompting attention to methods for extracting combustion information from existing sensing data. Mean-value combustion models for engines are unable to capture changes of combustion parameters. Furthermore, the methods of reconstructing combustion information using sensor signals mainly depend on the working state of the sensors, and the reliability of reconstructed values is directly influenced by sensor malfunctions. Due to the concentration of operating conditions of hybrid vehicles, the reliability of priori calibration map has increased. Therefore, a combustion information reconstruction method based on priori calibration information and the fused feature deviations of existing sensing signals is proposed and named the "Deviation-based Centroid Displacement Method" (DCDM).
Technical Paper

Development of an Ultra-Low Carbon Flex Dual-Fuel Ammonia Engine for Heavy-Duty Applications

2024-04-09
2024-01-2368
The work examined the practicality of converting a standard production 6 cylinder 8 litre heavy-duty diesel engine for flex dual-fuel operation with Ammonia as the main fuel. A small amount of diesel fuel (aka pilot) was used as an ignition source. Ammonia was injected into the intake ports of the engine cylinders during the intake stroke, while the original fuel injection equipment was retained and used for pilot diesel injection. A bespoke engine control unit was used to control the injection of both fuels and other engine parameters. The aim was to provide a cost-effective retrofitting technology for existing heavy-duty IC engines, to enable eco-friendly operation with minimal carbon emissions. The tests were carried out at a baseline speed of 600 rpm for the entire load range of the engine (10-90%), with minimum pilot diesel quantity and as high as 90% substitution ratio of ammonia for diesel fuel.
Technical Paper

Combustion Timing Control based on First Principal Component

2024-04-09
2024-01-2842
When an SI engine is equipped with individual cylinder pressure transducers, combustion timing of each cylinder can be precisely controlled by adjusting spark timing in real-time. In this paper, a novel method based on principal component analysis is developed to control the combustion timing with a significantly less computational burden than a conventional method.
Technical Paper

Improving the Performance of Diesel Engines by Bore Profile Control under Operating Conditions

2024-04-09
2024-01-2832
A cylinder block involves bore deformation due to assembling stress of cylinder head and thermal stress. This distortion is found to be the cause of the exacerbation of piston skirt friction and piston slap. This article presents a numerical and experimental study of the effect of an optimized bore profile on engine performance. A friction analysis of 3-dimentional elastohydrodynamic was applied for an estimation of the piston skirt friction. A cylinder bore with barrel shape under the part load operation point was assumed as an optimal bore profile in terms of piston skirt friction without compromising piston slap. From the simulation study, it was found that the piston secondary motion just after firing top dead center can be mitigated by narrower piston – bore clearance at upper position of the cylinder.
Technical Paper

Cylinder Head Insulation Plate, Design, Analysis and Testing for an Extreme High Efficiency Internal Combustion Engine

2024-04-09
2024-01-2831
The main objective of this paper is to describe the design, analysis and testing of a novel method of insulating the combustion chamber, which is key for efficiency demonstration on a new class of internal combustion engine (ICE). A recuperated split cycle engine (RSCE) has unique demands for heat loss reduction. In particular during the combustion event, to minimize the heat losses is a must to achieve high efficiency. The insulation is provided by a metal plate that is assembled into the cylinder head to line the combustion chamber surface. The design has been focused on reducing heat transfer surface area and exploiting contact gap thermal resistance between the upper surface of the plate and the cylinder head, thus reducing heat wasted to the coolant circuit. In this paper, the plate requirements, functions, design, analysis and test results from a research and development (R&D) program of a heavy duty (HD) recuperated split cycle engine are reported.
Technical Paper

The Influence of Fundamental Processing Parameters of Ultrasonic Shot Peening on Surface Characteristics of 7B50-T7751 Alloy

2024-04-09
2024-01-2681
Aluminum alloy has become an indispensable part of the automotive industry because of its excellent mechanical properties such as lightweight, high strength, high reliability, maintainability, and low cost. Aluminum alloy is used in automobiles, such as engine blocks, cylinder heads, intake manifolds, brake components, and fuel tanks. Fatigue and fracture are the main reasons for its engineering failure. Surface strengthening techniques, such as ultrasonic shot peening (USP), are often used to improve the fatigue resistance of aluminum alloys. This article expounds on the working principle of ultrasonic shot peening and elucidates the influence of USP process parameters on the surface characteristics of aluminum alloy. Experimental results observed the effects of USP parameters on surface properties such as surface roughness, microhardness, and surface morphology.
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