Search Results

The concept of the paper stems from the premise that the process of “heat release” in engines involves in essence the evolution and deposition of exothermic energy generated by combustion-events that can be governed promptly by a feedback, adaptive micro-electronic control system. The key to its realization is the principle of DISC (Direct Injection Stratified Charge) engine, implemented by a multi-jet system. The background and the salient features of such a system, referred to as a CCE (Controlled Combustion Engine), have been described in a companion paper (SAE 951961). Presented here are fundamental aspects of the model of the exothermic process and the intrinsic properties of its control system.

Active and semi-active suspensions have been evaluated for application on tractor/semi-trailer trucks using a pitch plane simulation model called “VESYM”. VESYM is a fully nonlinear time domain simulation model. This paper reviews the effect of alternative heavy truck suspensions on pavement damage by using the flexible pavement simulation program “VESYS”, It is shown that by estimating axle tire force and using this signal to modulate a semi-active shock absorber that significant reduction in pavement degradation can be achieved.

A framework for consideration of the effects of dynamic loads on pavement performance is presented. The paper discusses requisite research which will permit both the pavement engineer and the truck designer to effectively utilize such a framework to arrive at optimal solutions which will result in overall savings to the agencies responsible for design, construction, maintenance, and rehabilitation of pavement facilities and to the users of the facilities as well. Included is a discussion of needed research to evaluate: the dynamic response of jointed portland cement concrete pavements to load, the influence of dynamic loads on the development of rutting in asphalt concrete. pavements, and the development of new suspension concepts to reduce dynamic load variations with pavement roughness.