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Due to the recent trend emphasizing on environmental friendly, engine supercharger downsizing technology has been under development globally. In this report, the technical knowledge for high performance and high quality water-cooled CAC development is provided. For higher cooling performance, the optimum fin and tube core matrix water-cooled CAC, delivering best performance and quality have been developed. For higher reliability against thermal stress, the detail specifications of water-cooled CAC based on the transient analysis and the simulation technology have been established.

The large power mining dump truck usually has electric drive system for the harsh operating conditions of mining. The traction motor and multi-stage reducer are assembled in the limited space of the two rear wheels. The permanent magnet motor is often used as traction motor for its much advantage characteristic. However, the permanent magnet is particularly sensitive to the high temperatures since it can loose a part of magnetization when it is exposed to a high temperature. It is necessary to have better cooling system for improvement thermal performance of permanent magnet (PM) motor. The heat losses generated by permanent magnet motor in the off-road electric driving truck are cooled by the water to maintain the motor working effectively. This paper is focus on analyzing the thermal behavior of the PM motor numerically and experimentally.

The University of Maryland Space Systems Laboratory is developing the capability to simulate partial gravity levels for human operational activities through the use of ballast on body segments in the underwater environment. This capability will be important as NASA prepares to return to the Moon by the end of the next decade. The paper discusses various forms of partial gravity simulation used in the past, and derives a targeted set of applications for ballasted underwater simulations. Primary application of this technique is for static or quasistatic activities, such as collecting basic anthropometric data on reach envelopes or postural control, as well as accumulating an experience base on partial gravity habitat and vehicle design and operations.

Within the advances in CFD codes and HPC cluster size and processing capacities, multiphase CFD simulations became more feasible not only on research projects but also in production level. This work presents a simulation analysis of an automotive vehicle crossing certain height of water and analyzing the water ingestion by the air intake system and also the pressure load due to the water level and splashes reaching the vehicle. All the calculations were performed by Computational Fluid Dynamics, considering the car crossing 300mm of water height at 20 kph with a simulation time enough to the water reaches the whole car length. Results show the water path at the snorkel region and some part pressure load examples which can be used as an input for structural simulations to evaluate this part at this particular condition.

Physical testing of a vehicle wading through water is performed to gauge its capability to traverse through shallow to deep levels of water, wherein various vehicle performance parameters are observed, recorded and analysed. Jaguar Land Rover (JLR) has instigated and established a comprehensive CAE test procedure for assessing the same, which makes use of overset mesh (in a CFD environment) for a non-traditional approach to vehicle motion. The paper presents investigations made into the established wading physics, in order to optimise the splashing and water jet modelling. Large Scale Interface model was implemented instead of the previously standardised VOF-VOF fluid phase interaction model, and a comparison is made between the two. The implemented wheel rotation approach was scrutinised as well and appropriate inferences are drawn.

The vehicle WLTP and RDE homologation test cycles are pushing the engine technology toward the implementation of different solutions aimed to the exhaust gases emission reduction. The tightening of the policy on the Auxiliary Emission Strategy (A.E.S.), including those for the engine component protection, faces the Spark Ignited (S.I.) engines with the need to replace the fuel enrichment as a means to cool down both unburnt mixture and exhaust gases to accomplish with the inlet temperature turbine (TiT) limit. Among the whole technology solutions conceived to make SI engine operating at lambda 1.0 on the whole operation map, the water injection is one of the valuable candidates. Despite the fact that the water injection has been exploited in the past, the renewed interest in it requires a deep investigation in order to outcome its potential as well as its limits.

An automotive door latch that functions manually or electronically is a vital component of a door closure system. It primarily aims to provide security of the occupants by securing the door system by ensuring timely locking and unlocking of the doors. A wide range of factors like safety, ergonomics, and security influence the development of these latches to eliminate safety. With the growing trend and advancements, automotive electronics is becoming more complex and prevalent. Hence, any exposure of electrical/electronic components to water make them susceptible to short circuits, corrosion etc., thereby may make it the functionality of systems and increasing the chances of failure in these devices. Intrusion of water possible into the latch system can be disastrous depending on the climatic conditions. Stringent safety criteria have given rise to unconventional test methods that are time-consuming and hence necessitate virtual validation techniques.

This paper covers the development of computer simulation models of the Vapor Compression Distillation (VCD) process, the Super Critical Water Oxidation (SCWO) process, and two versions of a Vapor Phase Catalytic Ammonia Reduction (VPCAR) process. These process level models have combined into two Integrated Water Reclamation Systems (IWRS). Results from these integrated models, in conjunction with other data sources, have been used to develop a preliminary comparison of the two systems. Also discussed in this paper is the development of a Vapor Phase Catalytic Ammonia Reduction teststand and the development of a new urine analog for use with the teststand and computer models.

To date, almost all water used by the crew during space flight has been transported from Earth or generated in-flight as a by product of fuel cells and used for relatively short periods. With the United States' commitment to a permanent manned presence in space, this is no longer adequate. In order to resolve this problem, a plan for nearly complete recovery and recycling of water on-orbit has been formulated. Closed-loop water recovery on a scale applicable to a manned space station was first studied in the late 1960s and early 1970s. These tests, conducted with breadboard and early prototype equipment, demonstrated the feasibility of sustaining humans in a closed environment by a regenerative Environmental Control and Life Support System (ECLSS). However, increased awareness of potential hazards associated with long-term reuse of reclaimed water has resulted in the recognition that additional characterization of closed-loop water recovery systems and products is essential.

A numerical methodology using 3D computational fluid dynamics (CFD) was developed to simulate the water flows on vehicles in order to check the specifications under rain (visibility of door mirror by the driver, sealing…), or to evaluate washing efficiency (washing headlight, washing windshield …). The CFD method is constituted by a three step procedure. In the first step, the aerodynamic field around the vehicle is calculated with Powerflow software in a large domain. It uses a Lattice Boltzmann approach to solve airflow. The existing process of Powerflow computation developed by aerodynamic and aeroacoustic teams of Renault SAS was adapted to refine results in high gradients of velocity zones. In the second step, the field of air velocity vectors calculated with Powerflow is mapped towards a small domain where the water flow will be solved.

The Environmental Control System (ECS) of an aircraft provides thermal and pressure control of the engine bleed air for comfort of the crew members and passengers onboard. For safe and reliable operation of the ECS under complex operating environments, it is critical to detect and diagnose performance degradations in the system during early phases of fault evolution. One of the critical components of the ECS is the heat exchanger, which ensures proper cooling of the engine bleed air. This paper presents a wavelet-based fouling diagnosis approach for the heat exchanger.

A wavelet-based technique for reducing the impulsive character of sound recordings is presented. The amount of impulsive content removed may be adjusted by varying a statistical threshold. The technique is validated for a diesel idle sound-quality application. The wavelet-based modification produces a substantial decrease in impulsive character as verified by an objective sound-quality metric for engine “ticking”. Informal subjective assessment of the modified results found them to be realistic and free from artifacts. The procedure is expected to be useful for sound-quality simulation and target-setting for diesel powertrain noise and other automotive sounds containing both impulsive and non-impulsive content.

The future solution for the increasing air traffic density appears to be the free flight for which each airplane will have the possibility to choose its own trajectory and to follow it with only minor ground air traffic controllers' guides. The present paper deals with global collision avoidance which aims at separating aircraft taking into consideration the global traffic in a given area, contrarily to most of the existing approaches which are concerned with local traffic alone. The paper proposes a modeling of the global collision avoidance problem in the free flight context, in the horizontal plane, as a constrained optimization problem. A simulation example is performed in the end which shows the suitability of the proposed approach.

Visual Place Recognition (VPR) excels at providing a good location prior for autonomous vehicles to initialize the map-based visual SLAM system, especially when the environment changes after a long term. Condition change and viewpoint change, which influences features extracted from images, are two of the major challenges in recognizing a visited place. Existing VPR methods focus on developing the robustness of global feature to address them but ignore the benefits that local feature can auxiliarily offer. Therefore, we introduce a novel hierarchical place recognition method with both global and local features deriving from homologous VLAD to improve the VPR performance. Our model is weak supervised by GPS label and we design a fine-tuning strategy with a coupled triplet loss to make the model more suitable for extracting local features.

The Weapon Combat Effectiveness (WCE) analytics is very expensive, time-consuming, and dangerous in the real world because we have to create data from the real operations with a lot of people and weapons in the actual environment. The Modeling and Simulation (M&S) of many techniques are used for overcoming these limitations. Although the era of big data has emerged and achieved a great deal of success in a variety of fields, most of WCE research using the Defense Modeling and Simulation (DM&S) techniques studied have considered a lot of assumptions and limited scenarios without the help of big data technologies. Furthermore, WCE analytics using previous methodologies cannot help but get the bias results. This paper reviews and combines the basic knowledge for the new WCE analytics methodology using big data and M&S to overcome these problems of bias. Then this paper reviews the general overview of WCE, DM&S, and big data.

Off-road dump truck body is exposed to abrasive wear during handling of granular materials. The wear rate of body of dump truck has direct influence on maintenance and replacement during its service process. In this paper the discrete element method (DEM) is used to simulate the granular materials of dump truck. The wear of body floor during one dumping process can be achieved by cosimulation of FEM-DEM. The wear depth variation of body has the stochastic characteristic which can be modeled by Geometric Brownian Motion (GBM). The two parameters in the stochastic differential equation, drift coefficient and diffusion coefficient, can be estimated by the wear depth measuring data. It is possible to quantitatively predict the wear evolution of every grid point of the body floor by solving this stochastic differential equation. The simulation result of the wear model is helpful to optimize design of off-road dump truck body.

In internal combustion engine valves, wear often develops at the interface of the valve seat and the insert as a result of the high pressures produced by the combustion process at the moment of the closing event. An alternative to study the wear is by carrying out experimental tests in specific wear testing machines. The main drawback is that they are time consuming and expensive due to the need to carry out many tests for the usually observed scatter in the results. In the area of numerical methods, the wear simulation has been widely developed in the last years because it can solve complicated time consuming problems with general geometries. The aim of this work is to characterize the wear rate coefficients for bi-metallic pairs commonly used in internal combustion engine valves using experimental results and numerical solutions by using the Finite Element Method. Then, a numerical valve model is provided to demonstrate that the numerical and experimental solutions are in agreement.

The purpose of this SAE Aerospace Standard (AS) is to provide guidelines for the components and configurations that define the four versions of the Weather Support to Deicing Decision Making (WSDDM) winter weather nowcasting system.

The purpose of this SAE Aerospace Standard is to provide guidelines for the components and configurations that define the research and commercial versions of the Weather Support to Deicing Decision Making (WSDDM) winter weather nowcasting system.

Although computer models for vehicle and sub-system performance simulations have been developed and used extensively in the past several decades, there is currently a need to enhance the overall availability of these types of tools. Increasing demands on vehicle performance targets have intensified the need to obtain rapid feedback on the effects of vehicle modifications throughout the entire development cycle. At the same time, evolution of the PC and development of Web-based applications have contributed to the availability, accessibility, and user-friendliness of sophisticated computer analysis. Web engineering is an ideal approach in supporting globalization and is a cost-effective design-analysis integration business strategy. There is little doubt that this new approach will have positive impacts on product cost, quality, and development cycle time. This paper will show how Microsoft Excel and the Web can be powerful and effective tools in the development process.