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Two-side hot dip galvanized steel has not been used extensively for exposed automotive parts, despite its proven corrosion resistance. A major deterrent is its inconsistent surface finish after forming and painting. This paper describes a new two-side hot dip galvanized product which overcomes this surface characteristic. Its production, using conventional methods, and the product characteristics in relation to automotive exposed applications are described.

To effectively reduce the greenhouse gas emission, electric scooters have been developed and become a booming green transportation around the world. Most of these electric scooters possess a fixed reduction ratio in the powertrain, which makes them far from satisfactory-you can't have low cost, high performance and efficiency at the same time. However, as a silver bullet, one kind of two-speed transmission is developed. The two-speed transmission will shift automatically according to speed and throttle. An exquisite design with of a one-way clutch as well as a synchronizer effectively reduces the inevitable shocks while shifting. The electric scooter with such two-speed transmission will be launched on the market in 2013. This product successfully reaches the concept of high performance, high efficiency and rather low cost.

Discusses federal regulations of fuel economy as a restraint of vehicle performance. Develops a case for the need for greater selection of gear ratios over the range of intended vehicle use. Describes the musts and wants for vehicle design. Relates the musts and wants to two-speed axles as a solution. Describes a two-speed axle design.

The concept of using two-stage combustion in a spark ignition engine has been tested in a single cylinder CFR engine. The engine was operated over an equivalence ratio range of 1.5 to 2.2 to evaluate the first stage of combustion. The product gas was analyzed for H2, CO, CO2, and hydrocarbons. An atmospheric burner was operated with gasoline over the same equivalence ratio range of 1.5-2.2, and the resulting product gases were then burned in the CFR engine to test the second stage of combustion. Emissions of NOx, HC and CO of 0.1, 0.1, and 5 gm/IHP-hr were measured respectively. The engine indicated efficiency for the two-stage mode was essentially the same as for the single-stage mode.

Many diesel engines have to work at load profiles which, due to the low exhaust gas temperatures, necessitate active regeneration procedures to ensure continued engine operation and the reliability of the particulate filter. An active regeneration may be initiated via inner engine measures such as late injection. However, due to high maintenance interval and run time requirements for non-road applications the combustion of soot accumulated in the diesel particulate filter (DPF) often is realized via downstream processes. Known methods for this purpose are burner systems, systems based on downstream hydrocarbon injection (HCI) and subsequent hydrocarbon (HC)-conversion due to a catalyst or a combination of both. This paper describes an autarkic system using two-stage electro-thermal-supported hydrocarbon conversion. This system is capable to regenerate a DPF within the entire engine operating range and it is less complex than flame burner systems.

The most significant operation limit prohibiting the further reduction of the CO2 emissions of gasoline engines is the occurrence of knock. Thus, being able to predict the incidence of this phenomenon is of vital importance for the engine process simulation - a tool widely used in the engine development. Common knock models in the 0D/1D simulation are based on the calculation of a pre-reaction state of the unburnt mixture (also called knock integral), which is a simplified approach for modeling the progress of the chemical reactions in the end gas where knock occurs. Simulations of thousands of knocking single working cycles with a model representing the Entrainment model’s unburnt zone were performed using a detailed chemical reaction mechanism. The investigations showed that, at specific boundary conditions, the auto-ignition of the unburnt mixture resulting in knock happens in two stages.

This paper describes the exact method, which the author derived, for designing a two-stage leaf spring. The spring consists of a multileaf first stage, and tapered-leaf second stage. Using this method, the following can be determined: 1. Spring rates and stresses when all physical dimensions are known. 2. Leaf thickness and stresses for given rates. In the Appendix of this paper, a sample of a step-by-step calculation is given, which makes the whole problem easier to understand.

Recent diesel engines technology development has led to very compact and lightweight power plants. However those achievements (compactness × output power) faced some technical/economic constraints to be fully implemented in on-highway light vehicles, construction machines and agricultural tractors. When the installed power is upgraded on an existent equipment the most difficult issue to be solved is the power train. The very competitive worldwide environment is restricting more and more the added-cost technical solution to improve the vehicles performance/productivity. Two-Stage Power concept is a means to allow a turbochaged diesel engine to provide two different power curves in order to better explore the vehicle's transmission input torque capabilities with minor production plus cost. For every kind of equipment the engine is part of a complex system where all components must match in order to assure the desirable level of performance, reliability and durability.

The scavenging process is an incompressible process, which infers that it is a volumetric process. As such, its success depends on the volume of scavenging air. For a given port configuration, the higher the scavenging air volume the higher, the trapped fresh air volume in the cylinder. But this method leads to a less trapped fresh air mass in cylinder because of its lower density. The aim of two-stage scavenging is to increase the amount of the trapped fresh air mass. For this purpose the scavenging air is divided into two portions, namely warmed and unwarmed. During the first stage the cylinder is scavenged with the warmed portion resulting in a higher volumetric purity factor due to the higher scavenging air volume. The unwarmed air portion having a higher density is in the second stage to fill the already well-scavenged cylinder. The maximum fresh air mass in the cylinder is obtained if the two portions are divided almost equally.

Due to more stringent emission standards as well as customer requirements on performance improvement, model-based controls in diesel engines are becoming more and more common and necessary. In fact, as diesel engines becoming increasingly complicated with additional hardware components such as electonic throttle, EGR, VVT, VGT, as well as aftertreatment devices, the dynamics of the systems with more freedom of multiple actuators become much more sophisticated. With such complexity in the diesel engine systems, the traditional simple PI control, single-input single-output type of controls will not be good enough to address the multivariable interactions among subsystems, instead the advanced model-based, multi-input multi-output and coordinated supervisory controls almost become the only effective ways to improve system performance and achieve emission standards.

A method is described for matching turbines and compressors for two-stage turbocharging of 4-stroke diesel engines. The method is illustrated for a series turbocharged engine. Experimental results are presented which show that the method gives good predictions for the respective pressure ratios in the turbines and compressors and the overall engine performance.

By variation of the compression ratio the fuel consumption of high boosted gasoline engines can be reduced, due to operating with higher compression ratios at low load compared to an engine with fixed compression ratio. The two-stage VCR-system enables a high share of fuel saving potential relative to full variable systems. Considering a low cost manufacturability and a beneficial integratability into common engine architectures the length-adjustable conrod using an eccentric piston pin in the small eye has proved as the best concept. The adjustment is performed by a combination of gas and mass forces. This article describes the design of such a two-stage VCR-system as well as the functional testing under motored and fired engine operating conditions.

The Wave Disk Engine (WDE) is a novel engine that has the potential for higher efficiency and power density of power-generation systems. A recent version of wave disk engine architecture known as the two-stage WDE has been studied to address existing challenges of an existing WDE. After describing the engine operation, a cold air-standard thermodynamic model supporting the physical phenomena occurring inside the device is introduced to evaluate performance of the engine. The developed model is general and does not depend on the shape of the wave rotor, it can be applied to radial and axial combustion wave rotors integrated with turbomachinery devices. The analysis starts with predicting internal waves propagating inside the channels of the engine and linking various flow states to each other using thermodynamics relationships. The goal is to find analytical expressions of work output and efficiency in terms of known pressure and temperature ratios.

The alternator provides power to vehicle electrical loads with the battery, and its maximum current depends on various factors such as electrical load, engine speed, thermal condition, and other variables. Above all, thermal effects make alternator simulations more complicated. For example statically similar conditions may show different results according to the temperature variation for each alternator operation. This paper proposes a two-stage statistically-based model structure which separates dynamic thermal effects from steady state performance. The method was validated by experiments and shows good predictive performance, suitable for use in test reduction.

Recently, the demand for improving the merchantability of hood open system has been increasing. A novel concept hood open system was proposed by Hyundai Motor Company (HMC) in 2012, which was based on a two-step open latch mechanism. The new hood opening mechanism satisfies Safety laws and improves merchantability.

The paper describes the CFD analysis, the arrangement and the first experimental results of a single-cylinder engine that employs an innovative low-pressure hydrogen direct-injection system, characterized by low fuel rail pressure (12 bar) and consequent low residual storage pressure. The injection is split in two steps: at first hydrogen is metered and admitted into a small intermediate chamber by an electroinjector (a conventional one usually employed for CNG), next a mechanically actuated poppet valve, that allows high volumetric flow rates, times hydrogen injection from the intermediate chamber to the cylinder within a short time, despite the high hydrogen volume due to the low injection pressure. Injection must be properly timed to maintain pressure below 6 bar (or little more) in the intermediate chamber and thus keep sonic flow through the electroinjector, to maximize volumetric efficiency and to avoid backfire in the intake pipe.

Variable-Valve Actuation (VVA) provides improvements in engine efficiency, emissions, and performance by changing the valve lift and timing as a function of engine operating conditions. Two-Step VVA systems utilize two discrete valve-lift profiles and may be combined with continuously variable cam phasing. Two-Step VVA systems are relatively simple, low cost and easy to package on new and existing engines, and therefore, are attractive to engine manufacturers. The objective of this work was to optimize Two-Step system design and operation for maximum system benefits. An Early-Intake-Valve-Closing (EIVC) strategy was selected for warmed-up operating conditions, and a Late-Intake-Valve-Opening (LIVO) strategy was selected for the cold start. Engine modeling tools were used to fundamentally understand the thermodynamic and fluid mechanical processes involved.

The 8V-71 TAE engine was developed to provide improved fuel economy and reduced emissions. The effects of turbocharger-blower matching, air charge cooling, and combustion system design changes are presented. Steady state smoke reductions achieved through improved air utilization are compared with improvements in transient smoke on the Federal smoke test cycle.

The implementation of a single-cylinder two-stroke engine equipped with an auxiliary cylinder is described. The purpose of such a cylinder is to modify the diagram of flow induction through the inlet and transfer ports in the main cylinder in order to make it asymmetrical relative to tdc. Subsidiarily, the piston in the auxiliary cylinder is used to improve the balance of reciprocating forces. This engine has been developed for specific use in trial motorcycles.

The paper describes areas of unsatisfactory performance of most commercial outboard oils being marketed today. It describes the short-term testing techniques used to evaluate lubricating oils at Outboard Marine Engineering. These techniques evaluate oil performance with respect to deposits in the combustion chamber and on the piston skirts, piston ring sticking, lubrication ability, spark plug life, and preignition tendencies. Long-term testing techniques are also described. Finally, an ashless oil using an amide type additive with outstanding performance is described and its performance characteristics are shown.