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Test bogeys are valuable tools in providing guidance in design iterations as well as serving as gatekeepers in laboratory endurance tests for product certification. In addition, test bogeys have been used to screen manufacturing process-induced performance variations. Typically, the endurance test specification consists of descriptions of parts to be included in a test setup, the minimum number of test samples of the target component, the load, and the number of cycles, block cycle repeats, or test time to exceed without failure. To define these test bogeys, however, is a special challenge for heavy and medium duty vehicle applications. Oftentimes, neither a representative field duty nor a well-developed proving ground test cycle is available. Furthermore, there are numerous vehicle configurations and broad variations of application. A test bogey that is adequate for one case might not be suitable for a seemingly similar case.

It is well known that up-front FEA (finite element analysis) in product development will significantly reduce cycle time and improve product quality. The merit of using FEA in product design is evidenced by the mandate of its practice in the auto industry's QS9000 quality standard. Today, the usefulness of FEA in engineering product design is no longer an issue. Rather, the availability and cost for its extensive usage for product development is of concern. This is because until recently most FEA needed to be conducted by highly trained specialist. Recently, an alternative FEA implementation became feasible owing to the emergence of commercial software which takes advantage of several technological improvements such as P-element formulation and automatic mesh generation. As a result, some FEA jobs can now be conducted by less specialized engineers, offering the potential for fresh opportunities and challenges.

In the past decade many in-cylinder approaches were proposed for simultaneous reduction of NOx and smoke with various degrees of success in operation. In this paper, results from a novel and promising technique referred to as Interacting-Sprays injection concept is presented. A single-cylinder compression-ignition two-stroke research engine with optically-accessible head, mounted on a high-speed CFR engine crankcase was used to investigate the combustion and emission characteristics of this injection system. The Interacting-Sprays injection system produces two separate independently-control led sprays with a good degree of adjustability with regard to their fuel quantities and injection timings. The impingement schedule of the two sprays on each other at the right time and place in the combustion chamber is the key to the success of the Interacting-Sprays system.

Environmentally speaking, simultaneous reduction of smoke and NOx with minimal effects on the fuel economy has been an ideal goal for diesel engine designers. In the past decade several in-cylinder approaches were proposed with various degrees of success in operation. Here, we consider one promissing technique called as double (split) or staged injection. A single-cylinder compression-ignition two-stroke research engine with optically-accessible head, mounted on a high-speed CFR engine crankcase, was used to investigate the combustion and emission characteristics of a dual-injector injection system. The injection system produces two separate independently-controlled sprays with a good degree of adjustability with regard to their fuel quantities and injection timings. Results are presented to show the effects of the varied injection system characteristics on the combustion and exhaust emissions ( NOx and smoke).

Significant improvements in automotive fuel economy have been demonstrated by performance simulation of vehicles using the Vadetec Inertial Driveline. The novel driveline arrangement based upon a continuously variable-ratio mechanical transmission and the strategy for controlling the powertrain are discussed in this paper. The influence of CVT speed ratio range and efficiency on fuel economy is studied. The results of the performance simulation for a typical vehicle equipped with the Inertial Driveline are shown. These results indicate a 44% improvement in fuel economy when compared with the performance of the same vehicle equipped with a conventional driveline operating on the same duty cycle.