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This paper provides an overview about the consequences of a 14/42 V - Electrical Power Supply System for the Electrical Interconnection and Switching Technology. It presents design guidelines and solutions for connector systems including advanced applications like fuse and relay boxes and gives an overview of those existing connectors already suited for 42 V and even higher voltages. The problem of arcing due to the increased voltage is discussed for the case that mating and unmating under load has to be taken into consideration. Arcing also has a tremendous impact on the design of 42 V proof relays. Therefore, some basic results be presented along with proposals how these problems can be overcome by appropriate designs. Another part of the paper looks at the electrical power supply system itself. Here interconnection techniques for new battery systems are discussed. Finally, the chances for new technologies are highlighted.

The paper presents a numerical study aimed at converting a commercial lightweight 2-Stroke Indirect Injection (IDI) Diesel aircraft engine to Direct Injection(DI). First, a CFD-1D model of the IDI engine was built and calibrated against experiments at the dynamometer bench. This model is the baseline for the comparison between the IDI and the DI combustion systems. The DI chamber design was supported by extensive 3D-CFD simulations, using a customized version of the KIVA-3V code. Once a satisfactory combustion system was identified, its heat release and wall transfer patterns were entered in the CFD-1D model, and a comparison between the IDI and the DI engine was performed, considering the same Air-Fuel Ratio limit. It was found that the DI combustion system yields several advantages: better take-off performance (higher power output), lower fuel consumption at cruise conditions, improved altitude performance, reduced cooling requirements.

The paper describes a numerical study, supported by experiments, on light aircraft 2-Stroke Direct Injected Diesel engines, typically rated up to 110 kW (corresponding to about 150 imperial HP). The engines must be as light as possible and they are to be directly coupled to the propeller, without reduction drive. The ensuing main design constraints are: i) in-cylinder peak pressure as low as possible (typically, no more than 120 bar); ii) maximum rotational speed limited to 2600 rpm. As far as exhaust emissions are concerned, piston aircraft engines remain unregulated but lack of visible smoke is a customer requirement, so that a value of 1 is assumed as maximum Smoke number. For the reasons clarified in the paper, only three cylinder in line engines are investigated. Reference is made to two types of scavenging and combustion systems, designed by the authors with the assistance of state-of-the-art CFD tools and described in detail in a parallel paper.

The U. S. Coast Guard has recently put into service new 210 ft cutters designed for search and rescue work, law enforcement, oceanographic work, and possible future ASW. This paper outlines the structure and capabilities of the vessel. An important feature of the cutter is its helicopter handling facilities, which have greatly increased the cutter's search and rescue capability by extending the area it can cover. The cutter is the first in Coast Guard service to be powered by a combination diesel engine and gas turbine installation. The combination gives a top speed of 18 knots and a cruising range of 5000 miles.

A three-dimensional model for a direct injection stratified-charge rotary engine has been employed to study two modifications to the pocket geometry of the engine. In one modification, a pocket is located towards the leading edge of the rotor and is shown to produce recirculation within the pocket and faster burning. In the second modification, a two pocket rotor with two injectors and two spark plugs is studied. It appears that this should result in better utilization of the chamber air. It also appears that both modifications rhould result in higher efficiency of the direct-injected stratifiedcharge rotary engine. However extensive computations are required before a final conclusion is reached and before specific recommendations can be made.

Increased torque values passing from engine to transmission have, increasingly become a problem regarding shaft misalignment. Engineers are restricted with regard to applying ISO standards when investigating bearing life cycles as they tend only to cover normal [radial thrust] load conditions. Depending on the application, the need has arisen for numerical models to determine reduction in normal life cycles due to abnormal running conditions. The Simulia Finite Element package Abaqus v6.7 provides trends in the deformations, contact pressures and their respective distribution. It was found the most efficient profile, with regards to a uniform contact pressure, under both radial and misaligned conditions is the toroidal profile.

A three-dimensional model is used to compute the flow,sprays and combustion in a stratified-charge rotary engine. Wall temperatures estimated from available measurements are used as boundary conditions for the energy equation. The computations provide local and instantaneous heat fluxes on the rotor and the rotor housing. The instantaneous heat fluxes are integrated in time over one cycle of the rotor to obtain estimates of local cycle averaged heat flux through the rotor and the rotor housing. These are then used as boundary conditions in a thermal analysis of the rotor and rotor housing with known coolant-side flow rates and heat transfer coefficients. The thermal analysis is done using a finite-element three-dimensional code which provides updated estimates of the rotor and rotor housing wall temperatures. These wall temperatures agree within ±20°C of the measured wall temperatures.

This paper provides a survey about the consequences of a 42V Power Supply System for new vehicle projects, specially, its impact on directed project for Emerging Markets. At a first moment, it will be described new systems and its demand for additional power availability for future projects, such as electrical steering and brake systems; electrical air conditioning compressor; and electrical water and oil pumps. Following this subject, it will be presented possible alternatives for 14/42V Power Supply Systems, and also its impact over Power and Signal Distribution System components, such as connector, terminals, cables, relays, electrical centers, etc. Finally, the previous presented scenarios will be analyzed under a point of view for the Emerging Market demand for such new proposed systems, looking for best alternative driven.

A colorful series of 150 slides was presented tracing 5 HP to 1200 HP marine gear design evolution beginning in 1906, followed by pre-WWI developments, Liberty Aircraft engine usage and a 1924 to 1972 series of pleasure boat and work boat marine gear photographs. The entire slide presentation is available in 35 m.m. film strip and may be ordered (at cost) from the author, R. C. McRoberts, Twin Disc, Incorporated, Racine, Wisconsin, 53403, U.S.A. For short time usage, a loan film is available. This history of U. S. marine gear development includes information contributed by the Snow-Nabstedt Gear Corp., Capitol Gears, Inc., Paragon Gears, Inc., The Walter Machine Co., Inc., Detroit Diesel Allison Div. of General Motors Corp., Caterpillar Tractor Co., Warner Gear Div. Borg-Warner Corp. and Twin Disc, Incorporated.

The significance and the number of vehicle safety features enabled via connectivity continue to increase. OnStar, with its automatic airbag notification, was one of the first vehicle safety features that demonstrate the enhanced safety benefits of connectivity. Vehicle connectivity benefits have grown to include remote software updates, data analytics to aid with preventative maintenance and even to theft prevention and recovery. All of these services require available and reliable connectivity. However, except for the airbag notification, none have strict latency requirements. For example, software updates can generally be postponed till reliable connectivity is available. Data required for prognostic use cases can be stored and transmitted at a later time. A new set of use cases are emerging that do demand continuous, reliable and low latency connectivity. For example, remote control of autonomous vehicles may be required in unique situations.

Hayes Lemmerz has published papers (Ref 1 and 2 ) where different rotor designs were investigated to increase airflow velocity. We also have published the dynamometer test's data to show the 100 degrees F drop in temperature and 50% drop in deformation in rotors with 5% increase in airflow velocity (Ref 3). In the previous paper (Ref 4), the increase of 37.2% of airflow velocity in a 72 curved fin rotor design, was shown. In this paper, we are showing the results of dynamometer testing the 72 curved fin rotor design. When the 72 curve fin rotor design is compared to current production design, the 72 curve fin rotor design shows, a 140° F (60° C) drop in temperature during heating and cooling cycles. Hayes Lemmerz is testing this rotor design on standard vehicle tests ( LACT and DST). The results of these tests would be presented in another paper.

Hayes Lemmerz has pursued fin configurations in straight and curved fin rotors to achieve high airflow velocity. The largest increase in airflow velocity of 37.2% is achieved by curving fins to a specific entry and exit angle and increasing surface area by increasing fin number. There is a need for funneling air into the narrow entry in the hub area. The new “Hayes Air Director” successfully channels air into the curved fins. Hayes Lemmerz is in the process of casting rotors with curved fins and the air director idea. Dynamometer and vehicle tests will follow. The current renwood model of the rotor design shows 34.8 to 37.2% increase in airflow velocity when tested on the Hayes Airflow machine.

The 912 engine is a well known 4-cylinder horizontally opposed 4-stroke liquid-/air-cooled aircraft engine. The 912 family has a strong track record: 40 000 engines sold / 25 000 still in operation / 5 million flight hours annually. 88% of all light aircraft OEMs use Rotax engines. The 912iS is an evolution of the Rotax 912ULS carbureted engine. The “i” stands for electronic fuel injection which has been developed according to flight standards, providing a better fuel efficiency over the current 912ULS of more than 20% and in a range of 38% to 70% compared to other competitive engines in the light sport, ultra-light aircraft and the general aviation industry. BRP engineers have incorporated several technology enhancements. The fully redundant digital Engine Control Unit (ECU) offers a computer based electronic diagnostic system which makes it easier to diagnose and service the engine.

Brake squeal signatures (2 kHz to 18 kHz) have tonal content highly dependent on the specific brake system structural architecture. The challenge in minimizing squeal involves correctly identifying the conditions (temperature, apply pressure, rotor speed as some basic parameters) of occurrence, defining the underlying structural dynamics of the system and applying appropriate suppression solutions. The quantitative metric of improvement is the cumulative event percentage of occurrence. Design variables of the brake system and performance attribute targets extend the challenge beyond the level of just reducing noise. Consideration of material costs, manufacturing/assembly factors, durability, thermal management as well as other factors narrow the solution space significantly. Compressed late stage development is not uncommon in reaching acceptable levels of performance and is a primary reason for following a well defined process flow with provision for alternative solutions.

AS speeds and operational altitudes of modern aircraft continue to increase, it is becoming more and more important that the total drag of the airplane be reduced while the rate of heat dissipation per unit frontal area of radiator be kept as high as possible. The standard method of increasing the temperature difference between cooling medium and coolant has been to use ethylene glycol as a coolant, because its boiling point is much higher than that of water; however, in its pure state glycol has various disadvantages that are not present when a pressure water system is used. This is a sealed system for making use of the physical characteristics of the increase in boiling temperature with pressure. When the radiator receives more heat from the engine than it is dissipating, a small quantity of steam is generated inside the cylinder jackets. The resulting increase in pressure will cause the temperature to rise until a balance is restored between heat rejection and radiator dissipation.

In the summer of 1922 the Buick Company began experimenting with balloon tires. The first tires tested, being four-ply and 32 x 6.20 in. in size, produced a galloping action that was sufficient to prejudice the company's engineers against them, and the tests were discontinued. In addition to the galloping effect, other difficulties encountered included those usually present in steering, the development of wheel shimmying to a serious degree, the lack of proper clearance for external brakes because of the small 20-in. wheels, the excessively rapid wear of the tire tread, and the greater susceptibility to puncture. Leaks because of the pinching of the inner tubes also occurred. When, later, a set of 5.25-in. tires was tried on a smaller car, the galloping was noticeably less; but punctures were more numerous than was the case with high-pressure tires.

Computational Fluid Dynamics (CFD) surely has played a fundamental role in the design of the bodies and shapes of both commercial and racing vehicles in the last decades. This circumstance was mainly due to the connected substantial improvement in the design timings and to the possibility of producing numerous flow field and surface data that are difficult to obtain from a physical experimental method. Such a local analysis leads to a further understanding of the interactions of components with the overall aerodynamics. The development of wing performances, with respect to racing vehicles, has to deal with very short times but also with a very detailed description of the physics occurring. Starting from these constraints, a coupling procedure was developed by the joining of a CFD code with a Finite Element Method (FEM) structural code to better evaluate the aerodynamic performance of the wing deformed under the fluid dynamic loads.

The military aviation services pay a phenomenal price due to turbine engine stall. Several of the major factors which comprise a substantial portion of the total price are presented. Included are weapon system development time, operational limitations, field maintenance problems, overhaul costs and accident rates. Also presented, in a general fashion, are several technical approaches to the solution of turbine engine stall. Fundamental research and orderly development of basic engine components, power control systems, and airframe and installation factors are discussed. Emphasis is placed on the need for tighter control of production tolerances and the requirement for united efforts in the integration of components into a complete system.

Future avionics systems will have distributed architectures requiring computers and data transfer systems that can perform real-time calculations and are fault tolerant. Previously developed data bus standards such as MIL-STD-1553 are inadequate for these applications. Existing standards will not meet the needs of the future. They are too slow; have functions that are single-point failures; do not take advantage of new technologies such as fiber optics; and have poor efficiency when applied to distributed architectures. To meet the needs of data buses for distributed, real-time, fault-tolerant architectures of the future, a candidate High-Speed Data Bus (HSDB) protocol has been developed by the authors. This paper describes the performance characteristics of the candidate HSDB protocol including the following: Token-passing protocol. Token-passing best meets the needs because it is inherently distributed. Fiber optics implementation.

Newer automobiles have complex dynamic and stability controls due to regulations, competition, and safety concerns. More systems require testing at the subcomponent level to ensure proper operation in the final vehicle assembly. Many of the stability and navigation features originally designed for aircraft components are now being incorporated into automobiles. Certain types of motion test simulators were originally designed for testing aircraft sensors as: gyroscopes, inertial navigation systems (INS), inertial measurement units (IMU), and attitude heading and reference systems (AHARS) This same type of equipment is now used for automotive testing as: airbag fuse sensors, anti-skid sensors, rollover sensors, vehicle stabilization systems, active suspension sensors, and navigation systems.