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As vehicles are getting electrified and more intelligent, the energy consumption of the auxiliary system increases rapidly. The auxiliary battery acts as the backbone of the system to support the proper operation of the vehicle. It is important to ensure the auxiliary battery has enough energy to meet the basic loads regardless the vehicle is in park or running. However, the existing methods only focus on auxiliary energy management when the vehicle is in a dynamic event. To fulfill the gap, we propose an intelligent strategy that detects the low state of charge (SOC) condition, temporarily turns down the auxiliary loads based on their priorities and charges the auxiliary battery at the maximum efficiency of the auxiliary power unit. In addition, the proposed strategy allows the vehicle to get the park duration update and make intelligent decisions on charging the auxiliary battery.

Today’s advanced vehicles have high degree of interaction due to numerous sensors, actuators and also with complex communication within the control units. In order to hack a vehicle, it has to be within a certain range of communication. Here, we discuss the On-Board Diagnostic (OBD) regulations for next generation BEV/HEV, its vulnerabilities and cybersecurity threats that come with hacking. We propose three cybersecurity attack detection and defense methods: Cyber-Attack detection algorithm, Time-Based CAN Intrusion Detection Method and, Feistel Cipher Block Method. These control methods autonomously diagnose a cybersecurity problem in a vehicle’s onboard system using an OBD interface, such as OBD-II when a fault caused by a cyberattack is detected, All of this is achieved in an internal communication network structure. The results discussed here focus on the first detection method that is Cyber-Attack detection algorithm.

In the air conditioning system, flow-induced noise is very disturbing, including the noise generated in the expansion device and the heat exchangers. In the past few decades, most researches related to flow-induced noise focused on the relationship between the flow regimes near the expansion device and the amplitude of flow-induced noise when the measurements are not synched. In this paper, an experimental approach is used to explore the simultaneous relationships between flow-induced noise characteristics and flow regimes at the inlet of TXV of evaporators used in automobiles. A pumped R134a loop with microphones and transparent visualization sections is used to simulate the vapor compression system. Also, the paper evaluates the severity of flow-induced noise from not only the amplitude of noise but also the frequency of noise with a parameter called psychoacoustic annoyance (PA).

Carbon dioxide (CO2 or R744) is a promising next-generation refrigerant for mobile air-conditioning applications (MAC), which has the advantages of good heating performance in cold climates and environmental-friendly properties. This paper presents a simulation model of an integrated internal heat exchanger (IHX) and accumulator (Acc) using the finite volume method. The results are validated by a group of experimental data collected with different transcritical R744 mobile air-conditioner and heat pump (MHP) systems, and the error was within ±10%. The impacts of refrigerant mass flow rate and operating temperatures on the heat transfer rate of the IHX, improvement on refrigeration capacity and the liquid level in the Acc were studied. Results show that the net benefits of IHX are significant in AC mode, while it helps preventing flooding of the compressor in MHP mode.

This paper presents a cohesive set of engine-in-the-loop (EIL) studies examining the use of hierarchical model-predictive control for fuel consumption minimization in a class-8 heavy-duty truck intended to be equipped with Level-1 connectivity/automation. This work is motivated by the potential of connected/automated vehicle technologies to reduce fuel consumption in both urban/suburban and highway scenarios. The authors begin by presenting a hierarchical model-predictive control scheme that optimizes multiple chassis and powertrain functionalities for fuel consumption. These functionalities include: vehicle routing, arrival/departure at signalized intersections, speed trajectory optimization, platooning, predictive optimal gear shifting, and engine demand torque shaping. The primary optimization goal is to minimize fuel consumption, but the hierarchical controller explicitly accounts for other key objectives/constraints, including operator comfort and safe inter-vehicle spacing.

Flash boiling has drawn much attention recently for its ability to enhance spray atomization and vaporization, while providing better fuel/air mixing for gasoline direct injection engines. However, the behaviors of flash boiling spray with multi-component fuels have not been fully discovered. In this study, isooctane, ethanol and the mixtures of the two with three blend ratios were chosen as the fuels. Measurements were performed with constant fuel temperature while ambient pressures were varied to adjust the superheated degree. Macroscopic and microscopic characteristics of flash boiling spray were investigated using Diffused Back-Illumination (DBI) imaging and Phase Doppler Anemometry (PDA). Comparisons between flash boiling sprays with single component and binary fuel mixtures were performed to study the effect of fuel properties on spray structure as well as atomization and vaporization processes.

The spray structure and vaporization processes of flash-boiling sprays in a constant volume chamber under a wide range of superheated conditions were experimentally investigated by a high speed imaging technique. The Engine Combustion Network’s Spray G injector was used. Four fuels including gasoline, ethanol, and gasoline-ethanol blends E30 and E50 were investigated. Spray penetration length and spray width were correlated to the degree of the superheated degree, which is the ratio of the ambient pressure to saturated vapor pressure (pa/ps). It is found that parameter pa/ps is critical in describing the spray transformation under flash-boiling conditions. Three distinct stages namely the slight flash-boiling, the transition flash-boiling, and the flare flash-boiling are identified to describe the transformation of spray structures.

Inverted phi (ϕ)-sensitivity is a new approach of NOx reduction in compression-ignition (C.I.) engines. Previously, pure ethanol (E100) was selected as the preliminary test fuel in a single injection compression-ignition engine, and was shown to have good potential for low engine-out NOx emissions under low and medium load conditions due to its inverted ignition sequence. Under high load, however, the near-stoichiometric and non-homogeneous fuel/air distribution removes the effectiveness of the inverted ϕ-sensitivity. Therefore, it is desirable to recover the combustion sequence in the chamber such that the leaner region is burned before the near-stoichiometric region. When the combustion in near-stoichiometric region is inhibited, the temperature rise of that region is hindered and the formation of NOx is suppressed.

There are a few different ways in which biofuels can be sourced, with the most popular coming from agricultural sources. An alternative approach is to utilize biowaste. An estimated 20 million dry tons of volatile organic compounds, or biowaste, is annually deposited in US municipal wastewaters. Most of this biowaste energy content is not recovered and, as a result, the biowaste could be a massive potential source of renewable energy. Biocrude diesel is converted from wet biowaste via hydrothermal liquefaction (HTL). Three types of feedstocks (algae, swine manure, and food processing waste) were converted into biocrude oil via HTL. From the previous experiments done in an AVL 5402 single-cylinder diesel engine, it was observed that the presence of 20% of HTL in the blend performed similarly during combustion to pure diesel. By studying these mixtures in a constant volume chamber, these observations could be compared to the results in the diesel engine.

Automotive software complexity has been growing rapidly with time. The demand for automation in automotive segment including autonomous automobiles and software based products has caught the attention of researchers. Hence, it is necessary to check the complexity of automotive software and their reliability growth. Testing in the field of software artifact is resource intensive exercise. If project managers are able to put forward testing activities well then the testing resource consumptions may be much more resource/cost efficient. Reliability can be estimated during testing phase of software using software reliability growth models (SRGMs). A software package Computer Aided Software Reliability Estimation (CASRE) has many important SRGMs. These SRGMs are based on Non-Homogeneous Poisson Process (NHPP), Markov process or Bayesian models.

This article presents basic separation mechanisms with coalescing/impinging separators studied as the add-on to current popular centrifugal designs. The coalescence and impingement of oil on wire mesh and wave-plates are visualized and tested to investigate the impact of geometry and flow conditions on oil separation efficiency. Re-entrainment phenomenon is explained based on the mass balance. Oil mist flow at the swashplate reciprocating compressor discharge is quantified by video processing method to provide detailed information of the oil droplets. The physics behind oil separator is illustrated by visualization and measurement in this study, which gives useful guidelines for oil separator design and operation. The flow visualization shows the details of oil passing through different oil separation structures. Videos are quantified to provide information like droplet size distribution and liquid volume fraction.

Bio-butanol has been considered as a promising alternative fuel for internal combustion engines due to its advantageous physicochemical properties. However, the further development of bio-butanol is inhibited by its high recovery cost and low production efficiency. Hence, the goal of this study is to evaluate two upstream products from different fermentation processes of bio-butanol, namely acetone-butanol-ethanol (ABE) and isopropanol-butanol-ethanol (IBE), as alternative fuels for diesel. The experimental comparison is conducted on a single-cylinder and common-rail diesel engine under various main injection timings (MIT) and equivalent engine load (EEL) conditions. The experimental results show that ABE and IBE significantly affect the combustion phasing. The start of combustion (SOC) is retarded when ABE and IBE are mixed with diesel. Furthermore, the ABE/IBE-diesel blends are more sensitive to the changes in MIT compared with that of pure diesel.

In this work, an efficient and unified combustion model is introduced to simulate the flame propagation, diffusion-controlled combustion, and chemically-driven ignition in both SI and CI engine operation. The unified model is constructed upon a G-equation model which addresses the premixed flame propagation. The concept of the Livengood-Wu integral is used with tabulated ignition delay data to account for the chemical kinetics which is responsible for the spontaneous ignition of fuel-air mixture. A set of rigorously defined operations are used to couple the evolution of the G scalar field and the Livengood-Wu integral. The diffusion-controlled combustion is simulated equivalent to applying the Burke-Schumann limit. The combined model is tested in the simulation of the premixed SI combustion in a constant volume chamber, as well as the CI combustion in a conventional small bore diesel engine.

Reynolds-averaged Navier-Stokes (RANS) turbulence model has been used extensively for diesel engine simulations due to its computational efficiency and is expected to remain the workhorse computational fluid dynamics (CFD) tool for industry in the near future. Alternatively, large eddy simulations (LES) can potentially deal with complex flows and cover a large disparity of turbulence length scales, which makes this technique more and more attractive in the engine community. An n-dodecane spray flame (Spray A from Engine Combustion Network) was simulated using a dynamic structure LES model to understand the transient behavior of this turbulent flame. The liquid spray was treated with a traditional Lagrangian method and the gas-phase reaction was closed using a delta probability density function (PDF) combustion model. A 103-species skeletal mechanism was used for n-dodecane chemical kinetic model.

This paper introduces an intelligent energy distribution scheme for series plug-in hybrid electric vehicles (PHEVs) which incorporates the complexity of human driving behavior. Driving styles can have a significant impact on fuel consumption, but it is often unclear how one should drive to get the optimal fuel efficiency. Hybrid electric vehicles have been shown to improve fuel economy, reduce vehicle emissions and maintain drivability by incorporating electric motors into the drivetrain. Due to the highly complex system design and vehicle architecture, sophisticated energy management strategies (EMS) are required to optimize the vehicle performance. Currently, the power management system is based on static thresholds optimized on a fixed drive cycle for a given vehicle. This paper introduces an adaptive control method for EMS utilizing the complexity of human driving patterns for energy distribution in a series PHEV.

Biodiesel is a widely used biofuel in diesel engines, which is of particular interest as a renewable fuel because it possesses the similar properties as the diesel fuel. The pure soybean biodiesel was tested in an optical constant volume combustion chamber using natural flame luminosity and forward illumination light extinction (FILE) methods to explore the combustion process and soot distribution at various ambient temperatures (800 K and 1000 K) and oxygen concentrations (21%, 16%, 10.5%). Results indicated that, with a lower ambient temperature, the autoignition delay became longer for all three oxygen concentrations and more ambient air was entrained by spray jet and more fuel was burnt by premixed combustion. With less ambient oxygen concentration, the heat release rate showed not only a longer ignition delay but also longer combustion duration.

This paper develops a novel integrated navigational system for autonomous vehicle motion control. Vehicle control is defined in terms of the required vehicle steering angle, rate of steering change and speed. This paper proposes predictive control in the image plane. The proposed predictive control enables the navigation on the desired path, reduces the control complexity and increases the application space for multiple types of vehicles. The paper investigates vehicle control stability; especially in scenarios containing varying curvature turns and variable vehicle speeds. The primary emphasis of this paper is on vehicle control rather than scene analysis. To demonstrate the proposed vehicle control, a computer vision based multi-lane detection algorithm is introduced. The control strategy is applied such that the vehicle maintains position within the lane boundaries. Stability of the control algorithm is tested and demonstrated in multiple scenarios using 3-D simulation results.

A reconfigurable control system is an intelligent control system that detects faults within the system and adjusts its performance automatically to avoid mission failure, save lives, and reduce system maintenance costs. The concept was first successfully demonstrated by NASA between December 1989 and March 1990 on the F-15 flight control system (SRFCS), where software was integrated into the aircraft's digital flight control system to compensate for component loss by reconfiguring the remaining control loop. This was later adopted in the Boeing X-33. Other applications include modular robotics, reconfigurable computing structure, and reconfigurable helicopters. The motivation of this work is to test such control system designs for future long term space missions, more explicitly, the automation of life support systems.

An optically accessible single-cylinder high-speed direct-injection (HSDI) Diesel engine equipped with a Bosch common rail injection system was used to study the spray and combustion processes for European low sulfur diesel, bio-diesel, and their blends at different blending ratio. Influences of injection timing and fuel type on liquid fuel evolution and combustion characteristics were investigated under similar loads. The in-cylinder pressure was measured and the heat release rate was calculated. High-speed Mie-scattering technique was employed to visualize the liquid distribution and evolution. High-speed combustion video was also captured for all the studied cases using the same frame rate. NOx emissions were measured in the exhaust pipe. The experimental results indicated that for all of the conditions the heat release rate was dominated by a premixed combustion pattern and the heat release rate peak became smaller with injection timing retardation for all test fuels.

Biodiesel fuels and their blends with diesel are often used to reduce emissions from diesel engines. However, biodiesel has been shown to increase the NOx emissions. Operating a compression ignition engine in low-temperature combustion mode as well as using multiple injections can reduce NOx emissions. Experimental data for biodiesel are compared to those for diesel to show the effect of the biodiesel on the peak pressure, temperature, and emissions. Accurate prediction of biodiesel properties, combined with the KIVA 3V code, is used to investigate the combustion of biodiesel. The volume fraction of the cylinder that has temperatures greater than 2200 K is shown to directly affect the production of oxides of nitrogen. Biodiesel is shown to burn faster during the combustion events, though the ignition delay is often longer for biodiesel compared to diesel.