Development of a Duty Cycle for the Design and Optimization of Advanced, Heavy-Duty Port Drayage Trucks

2017 ◽  
Vol 2609 (1) ◽  
pp. 19-27 ◽  
Author(s):  
Pascal Amar ◽  
Parthav Desai ◽  
Aravind Kailas ◽  
Jean-Baptiste Gallo
Keyword(s):  
Real World ◽  
Duty Cycle ◽  
Greenhouse Gas Emission ◽  
Aerodynamic Drag ◽  
Electrical Power ◽  
Rolling Resistance ◽  
Conventional Vehicle ◽  
Design And Optimization ◽  
Vehicle Simulation ◽  
Drayage Trucks

Hybrid electric and electric trucks are potential technology solutions for reducing emissions at ports. However, developing an advanced, low-emission technology driveline entails thoroughly understanding typical truck operations in the real-world environment. This paper presents the work performed to develop a novel, more representative drayage duty cycle that characterizes drayage truck operations in the ports of San Pedro Bay in California. Unlike a conventional vehicle, an optimized hybrid driveline requires detailed understanding not only of torque requirements and vehicle speeds but also of the potential recovery of dynamic brake energy, charging opportunities, stopping and idling times, and many other operational requirements. Keeping this in mind, the duty cycle presented in this paper incorporated real-world, near-dock activities of Class 8 drayage trucks such as daily hours of operation, mileage, altitude profiles of routes, and idling and key-off patterns. The empirical duty cycle model was subsequently integrated with a complete vehicle simulation to explore the best solutions to minimize energy consumption for drayage applications in and around the ports. The analysis presented indicates that trucks spent most of the generated power in overcoming aerodynamic drag and rolling resistance of tires for a complete drayage shift and that electrical auxiliary loads dominated for near-dock operations because of idling and low-speed profiles. Therefore, achieving zero-emission near-dock operations entails focusing on auxiliary loads and rolling resistance. By using simulations, it was estimated that a hybrid truck with electrical power limited to about 100 kW could deliver a greenhouse gas emission reduction of about 30%.

Perspectives on greenhouse gas emission estimates based on Australian wastewater treatment plant operating data

2013 ◽  
Vol 69 (3) ◽  
pp. 451-463 ◽  
Author(s):  
D. W. de Haas ◽  
C. Pepperell ◽  
J. Foley
Keyword(s):  
Wastewater Treatment ◽  
Steady State ◽  
Greenhouse Gas ◽  
Greenhouse Gas Emission ◽  
Electrical Power ◽  
Research Work ◽  
Treatment Plant ◽  
Emission Factors ◽  
N2o Emissions ◽  
Operating Data

Primary operating data were collected from forty-six wastewater treatment plants (WWTPs) located across three states within Australia. The size range of plants was indicatively from 500 to 900,000 person equivalents. Direct and indirect greenhouse gas emissions were calculated using a mass balance approach and default emission factors, based on Australia's National Greenhouse Energy Reporting (NGER) scheme and IPCC guidelines. A Monte Carlo-type combined uncertainty analysis was applied to the some of the key emission factors in order to study sensitivity. The results suggest that Scope 2 (indirect emissions due to electrical power purchased from the grid) dominate the emissions profile for most of the plants (indicatively half to three quarters of the average estimated total emissions). This is only offset for the relatively small number of plants (in this study) that have significant on-site power generation from biogas, or where the water utility purchases grid electricity generated from renewable sources. For plants with anaerobic digestion, inventory data issues around theoretical biogas generation, capture and measurement were sometimes encountered that can skew reportable emissions using the NGER methodology. Typically, nitrous oxide (N2O) emissions dominated the Scope 1 (direct) emissions. However, N2O still only accounted for approximately 10 to 37% of total emissions. This conservative estimate is based on the ‘default’ NGER steady-state emission factor, which amounts to 1% of nitrogen removed through biological nitrification-denitrification processing in the plant (or indicatively 0.7 to 0.8% of plant influent total nitrogen). Current research suggests that true N2O emissions may be much lower and certainly not steady-state. The results of this study help to place in context research work that is focused on direct emissions from WWTPs (including N2O, methane and carbon dioxide of non-biogenic origin). For example, whereas non-biogenic CO2 contributions are relatively minor, it appears that opportunities to reduce indirect emissions as a result of modest savings in power consumption are at least in the same order as those from reducing N2O emissions. To avoid potentially high reportable emissions under NGER guidelines, particularly for methane, the onus is placed on WWTP managers to ensure that accurate plant monitoring operating records are kept.

scholarly journals Aerodynamic Drag and Rolling Resistance of Three-Wheelers

2009 ◽  
Vol 42 (4) ◽  
pp. 21
Author(s):  
J. A. K. S. Jayasinghe ◽  
B. S. Samarasiri ◽  
G. M. A. I. Rajakaruna
Keyword(s):  
Aerodynamic Drag ◽  
Rolling Resistance

Assessment and design of real world driving cycles targeted to the calibration of vehicles with electrified powertrain

2021 ◽  
pp. 146808742110387
Author(s):  
Stylianos Doulgeris ◽  
Zisimos Toumasatos ◽  
Maria Vittoria Prati ◽  
Carlo Beatrice ◽  
Zissis Samaras
Keyword(s):  
Real World ◽  
Simulation Models ◽  
Cost Effective ◽  
Operational Parameters ◽  
Virtual Design ◽  
Passenger Cars ◽  
Real World Data ◽  
Vehicle Simulation ◽  
Driving Cycles ◽  
The Impact

Vehicles’ powertrain electrification is one of the key measures adopted by manufacturers in order to develop low emissions vehicles and reduce the CO2 emissions from passenger cars. High complexity of electrified powertrains increases the demand of cost-effective tools that can be used during the design of such powertrain architectures. Objective of the study is the proposal of a series of real-world velocity profiles that can be used during virtual design. To that aim, using three state of the art plug-in hybrid vehicles, a combined experimental, and simulation approach is followed to derive generic real-world cycles that can be used for the evaluation of the overall energy efficiency of electrified powertrains. The vehicles were tested under standard real driving emissions routes, real-world routes with reversed order (compared to a standard real driving emissions route) of urban, rural, motorway, and routes with high slope variation. To enhance the experimental activities, additional virtual mission profiles simulated using vehicle simulation models. Outcome of the study consists of specific driving cycles, designed based on standard real-world route, and a methodology for real-world data analysis and evaluation, along with the results from the assessment of the impact of different operational parameters on the total electrified powertrain.

Development of a surrogate-based vehicle dynamic model to reduce computational delays in a driving simulator

SIMULATION ◽  
2016 ◽  
Vol 92 (12) ◽  
pp. 1087-1102 ◽  
Author(s):  
Nariman Fouladinejad ◽  
Nima Fouladinejad ◽  
Mohamad Kasim Abdul Jalil ◽  
Jamaludin Mohd Taib
Keyword(s):  
Real Time ◽  
Dynamic Model ◽  
Surrogate Model ◽  
Driving Simulator ◽  
Computational Time ◽  
Vehicle Dynamic ◽  
Approximation Techniques ◽  
Conventional Vehicle ◽  
Vehicle Simulation ◽  
Vehicle Dynamic Model

The development of a real-time driving simulator involves highly complex integrated and interdependent subsystems that require a large amount of computational time. When advanced hardware is unavailable for economic reasons, achieving real-time simulation is challenging, and thus delays are inevitable. Moreover, computational delays in the response of driving simulator subsystems reduce the fidelity of the simulation. In this paper, we propose a technique to decrease computational delays in a driving simulator. We used approximation techniques, sensitivity analysis, decomposition, and sampling techniques to develop a surrogate-based vehicle dynamic model (SBVDM). This global surrogate model can be used in place of the conventional vehicle dynamic model to reduce the computational burden while maintaining an acceptable accuracy. Our results showed that the surrogate model can significantly reduce computing costs compared to the computationally expensive conventional model. In addition, the response time of the SBVDM is nearly five times faster than the original simulation codes. Also, as a method to reduce hardware cost, the SBVDM was used and the results showed that most of the responses were accurate and acceptable in relation to longitudinal and lateral dynamics. Based on the results, the authors suggested that the proposed framework could be useful for developing low-cost vehicle simulation systems that require fast computational output.

A Study on the Aerodynamic Drag of a Non-Pneumatic Tire

2012 ◽  
Author(s):  
Hyeonu Heo ◽  
Jaehyung Ju ◽  
Doo-Man Kim ◽  
Sangwa Rhie
Keyword(s):  
Drag Force ◽  
Aerodynamic Drag ◽  
Fuel Efficiency ◽  
Rolling Resistance ◽  
Navier Stokes ◽  
Viscoelastic Materials ◽  
Complex Flow ◽  
Pneumatic Tire ◽  
Rans Method ◽  
Pneumatic Tires

An understanding of the flow around a tire in contact with the ground is important for when designing a fuel efficient tire as aerodynamic drag accounts for about one third of an entire vehicle’s rolling loss [1]. Recently, non-pneumatic tires (NPTs) have drawn attention mainly due to their low rolling resistance associated with the use of low viscoelastic materials in their construction. However, an NPT’s fuel efficiency should be re-evaluated in terms of aerodynamic drag: discrete flexible spokes in an NPT may cause more aerodynamic drag, resulting in greater rolling resistance. In this study, the aerodynamic flow around an NPT in contact with the ground is investigated for i) stationary and ii) rotating cases using the Reynolds-Averaged Navier-Stokes (RANS) method. The NPT has a more complex flow and a higher drag force than does the pneumatic counterpart.

scholarly journals Nonlinear Controllers for a Light-Weighted All-Electric Vehicle Using Chebyshev Neural Network

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Vikas Sharma ◽  
Shubhi Purwar
Keyword(s):  
Neural Network ◽  
Electric Vehicle ◽  
Aerodynamic Drag ◽  
Rolling Resistance ◽  
Adaptive Controller ◽  
Dc Motor ◽  
Resistance Coefficient ◽  
Chebyshev Neural Network ◽  
Nonlinear Controllers ◽  
Aerodynamic Drag Coefficient

Two nonlinear controllers are proposed for a light-weighted all-electric vehicle: Chebyshev neural network based backstepping controller and Chebyshev neural network based optimal adaptive controller. The electric vehicle (EV) is driven by DC motor. Both the controllers use Chebyshev neural network (CNN) to estimate the unknown nonlinearities. The unknown nonlinearities arise as it is not possible to precisely model the dynamics of an EV. Mass of passengers, resistance in the armature winding of the DC motor, aerodynamic drag coefficient and rolling resistance coefficient are assumed to be varying with time. The learning algorithms are derived from Lyapunov stability analysis, so that system-tracking stability and error convergence can be assured in the closed-loop system. The control algorithms for the EV system are developed and a driving cycle test is performed to test the control performance. The effectiveness of the proposed controllers is shown through simulation results.

Model-Based Estimation of Vehicle Aerodynamic Drag and Rolling Resistance

2015 ◽  
Vol 8 (2) ◽  
pp. 433-439 ◽  
Author(s):  
Darui Zhang ◽  
Andrej Ivanco ◽  
Zoran Filipi
Keyword(s):  
Aerodynamic Drag ◽  
Rolling Resistance ◽  
Model Based

scholarly journals In for the Long Haul

1999 ◽  
Vol 121 (02) ◽  
pp. 60-61
Author(s):  
Phil Kittredge ◽  
Thomas Urbas ◽  
Wayne Shintaku
Keyword(s):  
Real Time ◽  
Real World ◽  
Duty Cycle ◽  
Experimental Mechanics ◽  
Heavy Vehicle ◽  
Heavy Duty ◽  
The Real ◽  
Clutch Pedal ◽  
Heavy Duty Truck ◽  
Comprehensive Data

This article focuses on the fact that engineers at Meritor Automotive decided to learn how truck components really held up on the highways. So they outfitted an 18-wheeler with the company’s products for a 24,000-mile trial, in real time and in the real world. According to Meritor, the comprehensive data generated by the test has spurred improvements in brake components, clutches, drivelines, axles, and transmissions. The company claims that the data opens opportunities for improvements in virtually every type of heavy-duty truck component that Meritor builds. The engineers in Meritor’s experimental mechanics unit enlisted support from all the groups in the heavy vehicle division. The use of a channel to record clutch pedal displacement helped engineers improve their model for determining the number of clutch applications in a line-haul duty cycle. Meritor expects that this information will lead to improved durability of several clutch components.

scholarly journals Drag reduction mechanisms on a generic square-back vehicle using an optimised yaw-insensitive base cavity

2021 ◽  
Vol 62 (12) ◽  
Author(s):  
Magnus Urquhart ◽  
Max Varney ◽  
Simone Sebben ◽  
Martin Passmore
Keyword(s):  
Bluff Body ◽  
Greenhouse Gas Emission ◽  
Aerodynamic Drag ◽  
Base Flow ◽  
Key Factors ◽  
Passenger Vehicles ◽  
Reduction Mechanisms ◽  
Image Velocimetry ◽  
Base Cavity ◽  
Tapered Cavity

AbstractRegulations on global greenhouse gas emission are driving the development of more energy-efficient passenger vehicles. One of the key factors influencing energy consumption is the aerodynamic drag where a large portion of the drag is associated with the base wake. Environmental conditions such as wind can increase the drag associated with the separated base flow. This paper investigates an optimised yaw-insensitive base cavity on a square-back vehicle in steady crosswind. The test object is a simplified model scale bluff body, the Windsor geometry, with wheels. The model is tested experimentally with a straight cavity and a tapered cavity. The taper angles have been optimised numerically to improve the robustness to side wind in relation to drag. Base pressures and tomographic Particle Image Velocimetry of the full wake were measured in the wind tunnel. The results indicate that a cavity decreases the crossflow within the wake, increasing base pressure, therefore lowering drag. The additional optimised cavity tapering further reduces crossflow and results in a smaller wake with less losses. The overall wake unsteadiness is reduced by the cavity by minimising mixing in the shear layers as well as dampening wake motion. However, the coherent wake motions, indicative of a balanced wake, are increased by the investigated cavities. Graphical abstract

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