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Training / Education

Introduction to Commercial and Off-Road Vehicle Cooling Airflow Systems

2024-09-12
Vehicle functional requirements, emission regulations, and thermal limits all have a direct impact on the design of a powertrain cooling airflow system. Given the expected increase in emission-related heat rejection, suppliers and vehicle manufacturers must work together as partners in the design, selection, and packaging of cooling system components. The goal of this two-day course is to introduce engineers and managers to the basic principles of cooling airflow systems for commercial and off-road vehicles.
Technical Paper

Combustion Chamber Development for Flat Firedeck Heavy-Duty Natural Gas Engines

2024-04-09
2024-01-2115
The widely accepted best practice for spark-ignition combustion is the four-valve pent-roof chamber using a central sparkplug and incorporating tumble flow during the intake event. The bulk tumble flow readily breaks up during the compression stroke to fine-scale turbulent kinetic energy desired for rapid, robust combustion. The natural gas engines used in medium- and heavy-truck applications would benefit from a similar, high-tumble pent-roof combustion chamber. However, these engines are invariably derived from their higher-volume diesel counterparts, and the production volumes are insufficient to justify the amount of modification required to incorporate a pent-roof system. The objective of this multi-dimensional computational study was to develop a combustion chamber addressing the objectives of a pent-roof chamber while maintaining the flat firedeck and vertical valve orientation of the diesel engine.
Technical Paper

Assessing the Effects of Computational Model Parameters on Aerodynamic Noise Characteristics of a Heavy-Duty Diesel Engine Turbocharger Compressor at Full Operating Conditions

2024-04-09
2024-01-2352
In recent years, with the development of computing infrastructure and methods, the potential of numerical methods to reasonably predict aerodynamic noise in compressors has increased. However, aerodynamic acoustic modeling of complex geometries and flow systems is currently immature, mainly due to the greater challenges in accurately characterizing turbulent viscous flows. Therefore, recent advances in aerodynamic noise calculations for automotive turbocharger compressors were reviewed and a quantitative study of the effects for turbulence modeling (Shear-Stress Transport (SST) and Detached Eddy Simulation (DES)) and time-steps (2°and 4°) in numerical simulations on the performance and acoustic prediction of a compressor under full operating conditions was investigated. The results showed that for the compressor performance, the turbulence models and time-step parameters selection were within 1.5% error of the simulated and measured values for pressure ratio and efficiency.
Technical Paper

Introduction of the eGTU – an electric version of the Generic Truck Utility Aerodynamic Research Model

2024-04-09
2024-01-2273
Common aerodynamic research models have been used in aerodynamic research throughout the years to assist with the development and correlation of new testing and numerical techniques, in addition to being excellent tools for gathering fundamental knowledge about the physics around the vehicle. In 2020, the Generic Truck Utility (GTU) was introduced by Woodiga et al. following the success of the DrivAer, originally introduced by Heft et al. in 2012, in the automotive aerodynamics space but with a goal to capture the unique flow fields created by pickups and large SUVs. To date, a number of studies have been presented on the GTU (Howard et. al 2021, Gleason, Eugen 2022), however, with the increasing prevalence of electric vehicles (EVs), the authors have created additional configurations to create an EV-style underbody for the GTU. The existing GTU can change the cab and box lengths independently and has a rear cap with three different backlight angles to model SUVs.
Technical Paper

Control Strategy for Engine Silicone Oil Fan Clutch Based on Engine Cooling System

2024-04-09
2024-01-2234
In order to study the influence of engine silicone oil fan clutch on the performances of engine cooling system under different control strategies, a model of engine cooling system for commercial vehicle is established. The working characteristics of the silicone oil clutch and the measured performance parameters of the cooling system components are taken into account in our proposed model. Modeling methods for different silicone oil fan control strategies are also given. Using the established model, the performance parameters under different vehicle speeds, such as engine outlet coolant temperature and cooling fan power consumption, are calculated and analyzed. The in-suite measurement of the engine cooling system is carried out to get the temperatures of engine inlet and outlet from engine ECU. The model is validated by the comparison between the calculation and the measured results.
Technical Paper

A Holistic Approach to Next-Generation Polymer Composite Pickup Bed Development and Prototyping

2024-04-09
2024-01-2432
As we move toward electrification in future mobility, weight and cost reduction continue to be priorities in vehicle development. This has led to continued interest in advanced molding processes and holistic design to enable polymer materials for demanding structural applications such as pickup truck beds. In addition to performance, it is necessary to continue to improve styling, functionality, quality, and sustainability to exceed customer expectations in a competitive market. To support development of a lightweight bed design, a cross-functional team objectively explored the latest materials and manufacturing technologies for this application. In Phase 1 of this work, presented in 2022, the team considered a variety of alternatives for each functional area of the bed, including thermoplastic and thermoset materials with a range of processing technologies.
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

A Mechanical Energy Control Volume Approach Applied to CFD Simulations of Road Vehicles

2024-04-09
2024-01-2524
This paper presents a mechanical energy control volume analysis for incompressible flow around road vehicles using results from Detached Eddy Simulation Computational Fluid Dynamics calculations. The mechanical energy control volume method equates the work done by surface forces of the vehicle to the (i) kinetic energy flux and work done at the boundaries of the domain and (ii) the energy lost in the domain. Using a control volume approach allows the decomposition of contributions to the drag into volumetric and wake terms in the fluid domain, providing quantitative insight into which regions and mechanisms of the flow contribute the most to the overall drag. The formulation discussed herein includes terms for common features in automotive CFD simulations including shaft power (also known as ventilation drag) from rotating wheels, moving belts, and porous media.
Technical Paper

Experimental Study of Ammonia Combustion in a Heavy-Duty Diesel Engine Converted to Spark Ignition Operation

2024-04-09
2024-01-2371
Ammonia is one of the carbon-free alternatives considered for power generation and transportation sectors. But ammonia’s lower flame speed, higher ignition energy, and higher nitrogen oxides emissions are challenges in practical applications such as internal combustion engines. As a result, modifications in engine design and control and the use of a secondary fuel to initiate combustion such as natural gas are considered for ammonia-fueled engines. The higher-octane number of methane (the main component in natural gas) and ammonia allows for higher compression ratios, which in turn would increase the engine's thermal efficiency. One simple approach to initiate and control combustion for a high-octane fuel at higher compression ratios is to use a spark plug. This study experimentally investigated the operation of a heavy-duty compression ignition engine converted to spark ignition and ammonia-methane blends.
Technical Paper

Downsizing a Heavy-Duty Natural Gas Engine by Scaling the Air Handling System and Leveraging Phenomenological Combustion Model

2024-04-09
2024-01-2114
A potential route to reduce CO2 emissions from heavy-duty trucks is to combine low-carbon fuels and vehicle electrification/hybridization. Hybridization offers the potential to downsize the engine. Although engine downsizing in the light-duty sector can offer significant fuel economy savings mainly due to increased part-load efficiency, its benefits and downsides in heavy-duty engines are less clear. As there has been limited published research in this area to date, there is a lack of a standardized engine downsizing procedure. This paper aims to use an experimentally validated one-dimensional phenomenological combustion model in a commercial engine simulation software GT-Power alongside turbocharger scaling methods to develop downsized engines from a baseline 6-cylinder (2.2 L/cyl, 26 kW/L) pilot-ignition, direct-injection natural gas engine.
Technical Paper

Road Profile Reconstruction Based on Recurrent Neural Network Embedded with Attention Mechanism

2024-04-09
2024-01-2294
Recognizing road conditions using onboard sensors is significant for the performance of intelligent vehicles, since the road profile is a crucial factor for safe, smooth, and comfortable driving. In this paper, a recurrent neural network embedded with attention mechanisms is proposed to reconstruct the road profile sequence. Firstly, the road and vehicle sensor signals are obtained in a simulated environment by modeling the road, tire, and vehicle dynamic system. After that, the models under different working conditions are trained and tested using the collected data, and the attention weights of the trained model are then visualized to optimize inputs. Finally, field experiments on the real vehicle are conducted to collect real road profile data, combined with vehicle system simulation, to verify the performance of the proposed method.
Technical Paper

Optimizing the Dispense time of a battery from the Swappable charging station.

2024-04-09
2024-01-2026
In the emerging economies, there is a growing adoption of electric vehicles into fleet vehicles, especially light weight commercial vehicles, 2 wheelers and 3 wheelers. With the steady increase in this business area, there’s a demand for the innovation in the battery charging methodologies. The swappable charging method is one such charging method that’s gaining prominence. Battery swapping involves replacing an EV’s depleted battery with a fully charged one. This approach can significantly reduce wait times for drivers, as swapping batteries typically takes only a few minutes, similar to the time it takes to refuel an ICE vehicle. The objective of the present work is to optimize the charging process in the swappable charging station to prolong the battery life and also to reduce the waiting time. With battery swapping, EV owners can avoid concerns related to battery degradation, since they receive a fully charged, well-maintained battery during each swap.
Technical Paper

A Numerical Analysis of Terrain and Vehicle Characteristics in Off-Road Conditions Through Semi-Empirical Tyre Contact Modelling

2024-04-09
2024-01-2297
In the last decades the locomotion of wheeled and tracked vehicles on soft soils has been widely investigated due to the large interest in planetary, agricultural, and military applications. The development of a soil contact model which accurately represents the micro and macro-scale interactions plays a crucial role for the performance assessment in off-road conditions since vehicle traction and handling are strongly influenced by the soil characteristics. In this framework, the analysis of realistic operative conditions turns out to be a challenging research target. In this research work, a semi-empirical model describing the interaction between a tyre and homogeneous and fine-grained soils is developed in Matlab/Simulink. The stress distribution and the resulting forces at the contact are based on well-known terramechanics theories, such as pressure-sinkage Bekker’s approach and Mohr-Coulomb’s failure criterion.
Technical Paper

Fuzzy Control of Regenerative Braking on Pure Electric Garbage Truck Based on Particle Swarm Optimization

2024-04-09
2024-01-2145
In order to improve the braking energy recovery rate of pure electric garbage trucks and ensure the braking effect of garbage trucks, a strategy of optimizing the regenerative braking fuzzy control of garbage trucks by particle swarm optimization is proposed. A multi-stage front and rear wheel braking force distribution curve considering braking effect and braking energy recovery is designed. According to the vehicle demand braking force and braking strength, a hierarchical regenerative braking fuzzy control strategy is established. The first layer is based on the vehicle demand braking force, based on the front and rear axle braking force distribution scheme, and uses the fuzzy controller to realize the first distribution of the front axle braking force.
Technical Paper

Numerical Evaluation of Injection Parameters on Transient Heat Flux and Temperature Distribution of a Heavy-duty Diesel Engine Piston

2024-04-09
2024-01-2688
A major concern for a high-power density, heavy-duty engine is the durability of its components, which are subjected to high thermal loads from combustion. The thermal loads from combustion are unsteady and exhibit strong spatial gradients. Experimental techniques to characterize these thermal loads at high load conditions on a moving component such as the piston are challenging and expensive due to mechanical limitations. High performance computing has improved the capability of numerical techniques to predict these thermal loads with considerable accuracy. High-fidelity simulation techniques such as three-dimensional computational fluid dynamics and finite element thermal analysis were coupled offline and iterated by exchanging boundary conditions to predict the crank angle-resolved convective heat flux and surface temperature distribution on the piston of a heavy-duty diesel engine.
Technical Paper

Maximizing FCEV Stack Cooling Performance: Developing a Performance Prediction Model Based on Machine Learning for Evaporative Cooling Radiator

2024-04-09
2024-01-2586
Recently, regulations on automobile emissions, including Euro7, have been significantly strengthened to address climate change. The automobile industry is responding to these regulations by developing electric vehicles that use batteries and fuel-cells. Automobile emissions, including NOx are environmentally harmful, especially in the case of vehicles equipped with high-temperature and high-pressure diesel engines, which are more detrimental than gasoline engine. Therefore, the electrification of commercial vehicles using diesel engines could potentially yield even greater environmental benefits. For commercial vehicles battery electric vehicles(BEVs) require a large number of batteries to secure a long driving range, which reduces their maximum payload capacity. However, fuel-cell electric vehicles(FCEVs) use hydrogen as a fuel to generate electricity, allowing them to achieve a long driving range with relatively fewer batteries.
Technical Paper

Integrating Machine Learning in Pedestrian Forensics: A Comprehensive Tool for Analysing Pedestrian Collisions

2024-04-09
2024-01-2468
In 2022, 385 pedestrians were killed in Great Britain, whilst 5,901 were reported to be seriously injured. Although these rates have improved since 2004, they have worsened since 2020. Due to the nature of the interaction and the physics involved, these collisions are extremely complex. Analysis of these accidents becomes difficult due to restricted access to cameras and vehicle data, as well as limited investigation techniques, which are frequently based on the Searle throw distance estimate. The current forensic methods usually require lengthy investigations and focus mainly on determining the vehicle’s impact speed to ascertain the driver’s degree of liability. Current accident reconstruction methods cannot reliably calculate the pedestrian kinematics behaviour at the time of impact, nor are they capable of solving hit-and-run scenarios without relying on additional evidence, which this research addresses.
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

Maximum Pulling Force Calculation of Permanent Magnet Tractor Motors in Electric Vehicle Applications

2024-04-09
2024-01-2217
In electric vehicle applications, the majority of the traction motors can be categorized as Permanent Magnet (PM) motors due to their outstanding performance. As indicated in the name, there are strong permanent magnets used inside the rotor of the motor, which interacts with the stator and causes strong magnetic pulling force during the assembly process. How to estimate this magnetic pulling force can be critical for manufacturing safety and efficiency. In this paper, a full 3D magnetostatic model has been proposed to calculate the baseline force using a dummy non-slotted cylinder stator and a simplified rotor for less meshing elements. Then, the full 360 deg model is simplified to a 90deg quarter model based on motor symmetry to save the simulation time from 2 days to 4 hours. A rotor position sweep was conducted using the quarter model to find the max pulling force position. The result shows that the max pulling force happens when the rotor is 1mm overlapping with the stator core.
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.
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