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Technical Paper


The quality of production is defined by the actual deviations from the requirements stated in design and technological documentation including drawings. In this article the problem of ensuring steady decrease in quantity of deviations from these requirements by production is considered. Carrying out preventive actions, in combination with control of time and costs of correction of discrepancies of such decrease it is possible to achieve. For the solution of an objective the method of the modified FMEA using parameters and levels of ranging as elements of operation of technological process where at a design stage of a product are set structure, is offered and are adjusted on the basis of feedback of production and operation. Such statement of a problem demands automation of collecting and data processing which can be used for creation of the knowledge base necessary for management of productions.
Technical Paper

Simulation of aircraft assembly via ASRP software

ASRP (Assembly Simulation of Riveting Process) software is a special tool for modelling assembly process for large scale airframe parts. On the base of variation simulation, ASRP provides a convenient way to analyze, verify and optimize the arrangement of temporary fasteners. During the airframe assembly process certain criteria on the residual gap between parts must be fulfilled. The numerical approach realized in ASRP allows one to evaluate the quality of contact on every stage of the assembly process and solve verification and optimization problems for temporary fastener patterns. The paper is devoted to description of several specialized approaches that combine statistical analysis of measured data and numerical simulation using high-performance computing for optimization of fastener patterns, calculation of forces in fasteners needed to close initial gaps and identification of hazardous areas in junction regions.
Technical Paper

Quantification of Linear Approximation Error for Model Predictive Control of Spark Ignited Turbocharged Engines

Modern turbocharged spark-ignition engines are being equipped with an increasing number of control actuators to simultaneously meet fuel economy, emissions and performance targets. The response time variations between a given set of engine control actuators tends to be significant during transients and necessitate highly complex actuator scheduling routines. Model Predictive Control (MPC) algorithms have the potential to significantly reduce calibration and control tuning efforts as compared to current methodologies that are designed around integration of multiple single-input single-output sub-system controllers. MPC systems simultaneously generate all actuator responses by using a combination of current engine conditions and optimization of a control-oriented plant model. To achieve real-time control the engine model and optimization processes must be computationally efficient without sacrificing effectiveness.
Technical Paper

Possibilities of wall heat transfer measurements at a supercharged Euro IV heavy-duty Diesel engine with high EGR-rates, an in-cylinder peak pressure of 250 bar and injection pressure up to 2500 bar

A raise of efficiency is, especially for CV, the strongest selling point concerning the TCO. Accompanied by legislations, with contradictive development demands, satisfying solutions have to be found. The analysis of energy losses in modern engines shows three influencing parameters. The losses resulting from taking real gas properties and non-ideal combustion into account have only a limited potential for gains, wall heat losses are currently believed to have the highest optimization potential. Critical for the occurrence of these losses is the wall heat transfer, which can be described by coefficients. To reduce WHT accompanying losses a decrease of energy transfer between combustion gas and combustion chamber wall is necessary. A measurement of heat fluxes is needed to determine the WHT relations at the combustion chamber of an engine. Methods to reduce the WHT can be developed and their effectiveness can be evaluated.

Formed Tube Ends for Hose Connections and Hose Fittings


This SAE Standard provides general and dimensional specifications for formed tube ends and hose fittings. These connections are intended for general applications in low pressure automotive and hydraulic systems on automotive, industrial, and commercial products. The fittings shown in Figures 2 and 3 are intended to be retained by hose clamps as specified in SAE J1508.

It is recommended that where step sizes or additional types of fittings are required, they be designed to conform with the specifications of this document insofar as they may apply. The following general specifications shall supplement the dimensional data contained in the tables with respect to all unspecified detail.