Your Selections

University of Birmingham
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Events

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Determination of a Tyre’s Rolling Resistance Using Parallel Rheological Framework

University of Birmingham-Hamad Sarhan Aldhufairi, Oluremi Olatunbosun, Khamis Essa
Published 2019-06-20 by SAE International in United States
Nowadays, rolling resistance sits at the core of tyre development goals because of its considerable effect on the car’s fuel economy. In contrast to the experimental method, the finite element (FE) method offers an inexpensive and efficient estimation technique. However, the FE technique is yet to be a fully developed product particularly for rolling-resistance estimation. An assessment is conducted to study the role of material viscoelasticity representation in FE, in linear and non-linear forms, through the use of Prony series and parallel rheological framework (PRF) models, respectively, on the tyre’s rolling-resistance calculation and its accuracy. A unique approach was introduced to estimate the rolling resistance according to the tyre’s hysteresis energy coefficient. The non-linear PRF choice resulted in rolling-resistance calculations that reasonably match that of the experimental work and the literature for various vertical load and inflation cases, whereas the Prony series option was found irresponsive to the tyre’s deformation in which it gave unreliable and infinitesimal outputs.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Coupled Eulerian Lagrangian Finite Element Model of Drilling Titanium and Aluminium Alloys

SAE International Journal of Aerospace

University of Birmingham-Ali Mohamed Abdelhafeez, Sein Leung Soo, David Aspinwall
Airbus Operations Limited-Anthony Dowson
  • Journal Article
  • 2016-01-2126
Published 2016-09-27 by SAE International in United States
Despite the increasing use of carbon fibre reinforced plastic (CFRP) composites, titanium and aluminium alloys still constitute a significant proportion of modern civil aircraft structures, which are primarily assembled via mechanical joining techniques. Drilling of fastening holes is therefore a critical operation, which has to meet stringent geometric tolerance and integrity criteria. The paper details the development of a three-dimensional (3D) finite element (FE) model for drilling aerospace grade aluminium (AA7010-T7451 and AA2024-T351) and titanium (Ti-6Al-4V) alloys. The FE simulation employed a Coupled Eulerian Lagrangian (CEL) technique. The cutting tool was modelled according to a Lagrangian formulation in which the mesh follows the material displacement while the workpiece was represented by a non-translating and material deformation independent Eulerian mesh. The performance of the CEL based simulation was also benchmarked against an equivalent pure Lagrangian model (both tool and workpiece mesh deforms with the material). The geometry of commercially supplied twin-fluted twist drills utilised in experimental validation trials were imported into the model. Cutting speed (m/min)/ feed rate (mm/rev) combinations were 50/0.08 and 150/0.24 for the…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Improving Cold Start and Transient Performance of Automotive Diesel Engine at Low Ambient Temperatures

University of Birmingham-Arumugam Sakunthalai Ramadhas, Hongming Xu
Published 2016-04-05 by SAE International in United States
Ambient temperature has significant impact on engine start ability and cold start emissions from diesel engines. These cold start emissions are accounted for substantial amount of the overall regulatory driving cycle emissions like NEDC or FTP. It is likely to implement the low temperature emissions tests for diesel vehicles, which is currently applicable only for gasoline vehicles. This paper investigates the potential of the intake heating strategy on reducing the driving cycle emissions from the latest generation of turbocharged common rail direct injection diesel engines at low ambient temperature conditions. For this investigation an air heater was installed upstream of the intake manifold and New European Driving Cycle (NEDC) tests were conducted at -7°C ambient temperature conditions for the different intake air temperatures. Intake air heating reduced the cranking time and improved the fuel economy at low ambient temperatures. Intake air temperatures of 5° and 15°C reduced HC emissions by 40% and 65%, and NOx by 8.5% and 10%, respectively compared to that of at -7°C in the first part of NEDC. The instantaneous emission…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Influence of Coolant Temperature on Cold Start Performance of Diesel Passenger Car in Cold Environment

University of Birmingham-A S Ramadhas, Hongming Xu
Published 2016-02-01 by SAE International in United States
Diesel engines are the versatile power source and is widely used in passenger car and commercial vehicle applications. Environmental temperature conditions, fuel quality, fuel injection strategies and lubricant have influence on cold start performance of the diesel engines. Strategies to overcome the cold start problem at very low ambient temperature include preheating of intake air, coolant, cylinder block. The present research work investigates the effect of coolant temperatures on passenger car diesel engine’s performance and exhaust emission characteristics during the cold start at cold ambient temperature conditions. The engine is soaked in the -7°C environment for 6 hours. The engine coolant is preheated to the desired coolant temperatures of 10 and 20°C by an external heater and the start ability tests were performed. The coolant temperature of 10°C in the -7 °C environment improved the fuel combustion and thereby reduced the cranking period by half; reduced the peak HC emissions and NOx emissions by 85% and 30% respectively. The cold ambient conditions increased the accumulation mode particles by 60% and decreased the nucleation particles by…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Numerical Investigation of GDI Injector Nozzle Geometry on Spray Characteristics

University of Birmingham-Po-Wen Tu, Hongming Xu, Dhananjay Kumar Srivastava, Karl Dean, Daliang Jing
Jaguar Land Rover-Li Cao, Adam Weall
Published 2015-09-01 by SAE International in United States
The large eddy simulation (LES) with Volume of Fluid (VOF) interface tracking method in Ansys-FLUENT has been used to study the effects of nozzle hole geometrical parameters on gasoline direct injection (GDI) fuel injectors, namely the effect of inner hole length/diameter (L/D) ratio and counter-bore diameters on near field spray characteristics. Using iso-octane as a model fuel at the fuel injection pressure of 200 bar, the results showed that the L/D ratio variation of the inner hole has a more significant influence on the spray characteristics than the counter-bore diameter variation. Reducing the L/D ratio effectively increases the mass flow rate, velocity, spray angle and reduces the droplet size and breakup length. The increased spray angle results in wall impingements inside the counter-bore cavity, particularly for L/D=1 which can potentially lead to increased deposit accumulation inside fuel injectors. The influences of the counter-bore diameter become more obvious with decreased L/D ratio. For the lower L/D ratio, the sprays with large included angles are more vulnerable to the air entrained into the counter-bore cavity and the…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Visualization of the Gas Flow Field within a Diesel Particulate Filter Using Magnetic Resonance Imaging

University of Birmingham-Isaline Lefort
Johnson Matthey Technology Centre-Andrew P. E. York, Timothy C. Watling
Published 2015-09-01 by SAE International in United States
In recent years magnetic resonance imaging (MRI) has been shown to be an attractive method for fluid flow visualization. In this work, we show how MRI velocimetry techniques can be used to non-invasively investigate and visualize the hydrodynamics of exhaust gas in a diesel particulate filter (DPF), both when clean and after loading with diesel engine exhaust particulate matter. The measurements have been used to directly measure the gas flow in the inlet and outlet channels of the DPF, both axial profiles along the length and profiles across the channel diameter. Further, from this information we show that it is possible to indirectly ascertain the superficial wall-flow gas velocity and the soot loading profiles along the filter channel length.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

FE-Based Tire Loading Estimation for Developing Strain-Based Intelligent Tire System

University of Birmingham-Xiaoguang Yang, Oluremi Olatunbosun
Federal Highway Administration-Emmanuel Bolarinwa
Published 2015-04-14 by SAE International in United States
The development of intelligent tire technology from concept to application covers multi-disciplinary fields. During the course of development, the computational method can play a significant role in understanding tire behavior, assisting in the design of the intelligent tire prototype system and in developing tire parameters estimation algorithm, etc. In this paper, a finite element tire model was adopted for developing a strain-based intelligent tire system. The finite element tire model was created considering the tire's composite structure and nonlinear properties of its constituent materials, and the FE model was also validated by physical tests. The FE model is used to study tire strain characteristics by steady state simulation for straight line rolling, traction and braking, as well as cornering. Tire loading conditions were estimated by feature extraction and data fitting. This process forms the fundamentals for identifying tire loadings from strain information at potential sensor locations. Finally, the pros and cons of applying finite element tire model in developing tire loading estimation algorithm are discussed. A perspective of the role of FE-based method in developing…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Artificial Road Load Generation Using Artificial Neural Networks

University of Birmingham-Adebola Ogunoiki, Oluremi Olatunbosun
Published 2015-04-14 by SAE International in United States
This research proposes the use of Artificial Neural Networks (ANN) to predict the road input for road load data generation for variants of a vehicle as vehicle parameters are modified. This is important to the design engineers while the vehicle variant is still in the initial stages of development, hence no prototypes are available and accurate proving ground data acquisition is not possible. ANNs are, with adequate training, capable of representing the complex relationships between inputs and outputs. This research explores the implementation of the ANN to predict road input for vehicle variants using a quarter vehicle test rig. The training and testing data for this research are collected from a validated quarter vehicle model.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Characterisation of the Effects of Vehicle Parameter Variations on Vehicle Road Load Data

University of Birmingham-Adebola Ogunoiki, Oluremi Olatunbosun
Published 2015-04-14 by SAE International in United States
This paper presents a statistical characterisation of the effects of variations in vehicle parameters on vehicle road load data using a quarter vehicle as a case study.A model of a quarter vehicle test rig constructed from a commercial SUV is created in a multi-body dynamics (MBD) simulation environment to reproduce the real-life behaviour of the SUV. The model is thereafter validated by correlating the response data collected from both the model and laboratory test rig to the same road input. In order to ensure that only the effects of the variation of the vehicle parameters are captured, a time domain drive signal for a kerb strike road event on the physical vehicle is generated from the proving ground data collected during durability testing of the vehicle. The variants of the quarter vehicle are excited by the generated drive file and the effects of the parameter variations are characterised in terms of peaks, root mean square values and ranges of the sprung and unsprung acceleration as well as the forces in the suspension components.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Experimental Investigation of Different Blends of Diesel and Gasoline (Dieseline) in a CI Engine

SAE International Journal of Engines

University of Birmingham-Fan Zhang, Soheil Zeraati Rezaei, Hongming Xu
Tsinghua Univ.-Shi-Jin Shuai
  • Journal Article
  • 2014-01-2686
Published 2014-10-13 by SAE International in United States
Combustion behaviour and emissions characteristics of different blending ratios of diesel and gasoline fuels (Dieseline) were investigated in a light-duty 4-cylinder compression-ignition (CI) engine operating on partially premixed compression ignition (PPCI) mode. Experiments show that increasing volatility and reducing cetane number of fuels can help promote PPCI and consequently reduce particulate matter (PM) emissions while oxides of nitrogen (NOx) emissions reduction depends on the engine load. Three different blends, 0% (G0), 20% (G20) and 50% (G50) of gasoline mixed with diesel by volume, were studied and results were compared to the diesel-baseline with the same combustion phasing for all experiments. Engine speed was fixed at 1800rpm, while the engine load was varied from 1.38 to 7.85 bar BMEP with the exhaust gas recirculation (EGR) application. Results show that, compared to the diesel baseline, the total particle number concentration of G50 was reduced by up to 50% and 90% and count median diameter (CMD) was reduced by 25% and 75% at medium and low loads respectively. The G50 blend had the lowest smoke emission level (0.5…
Annotation ability available