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The purpose of the article is to describe different possibilities of the innovative concept of the closed-loop test rig. The performed tests will be demonstrated with the example of measured data. Firstly the article will describe in detail the design of the test stand and both torque units. The power flow in the closed-loop circuit will be described and measured to find out the power losses of all parts. The measurement will be done for manual and planetary pretensioning mechanism. The comparison of the overall efficiency and demanded power for both torque units will be given. For evaluation of gearbox efficiency, the magnitude of power losses will be evaluated for different revolutions, torque levels and shifted speeds. For a long term tests, the unmanned operation is prepared. For this purpose is the stand equipped with electromechanical shift robots. The description of its concept and functioning will be part of the paper.

Twenty vehicles from eighteen schools competed in the Second SAE Super Mileage Competition at the Eaton Proving Grounds, Marshall, Michigan, on June 6, 1981. Of these, fifteen completed all of the events with the winner obtaining 702 miles/gallon (298.4 KM/liter). The designs of the successful vehicles were quite varied but stressed lightness, aerodynamic streamlining, low rolling resistance and efficient drive trains. Some engines were also modified- to improve efficiency. The integrated optimization of all variables within the severe constraints of budget, manpower, time and manufacturing facilities presented an excellent engineering experience for the students.

Vehicle operation during cold-start powertrain conditions can have a significant impact on drivability, fuel economy and tailpipe emissions in modern passenger vehicles. As efforts continue to maximize fuel economy in passenger vehicles, considerable engineering resources are being spent in order to reduce the consumption penalties incurred shortly after engine start and during powertrain warmup while maintaining suitably low levels of tailpipe emissions. Engine downsizing, advanced transmissions and hybrid-electric architecture can each have an appreciable effect on cold-start strategy and its impact on fuel economy. This work seeks to explore the cold-start strategy of several passenger vehicles with different powertrain architectures and to understand the resulting fuel economy impact relative to warm powertrain operation. To this end, four vehicles were chosen with different powertrain architectures.

This paper introduces research work on 1-D model of Roots type supercharger with helical gears using 1-D simulation tool. Today, passenger car engine design follows approach of downsizing and the reduction of number of engine cylinders. Superchargers alone or their combination with turbochargers can fulfill low-end demands on engine torque for such engines. Moreover, low temperature combustion of lean mixture at low engine loads becomes popular (HCCI, PCCI) requiring high boost pressure of EGR/fresh air mixture at low exhaust gas temperature, which poses too high demands on turbocharger efficiency. The main objective of this paper is to describe Roots charger features and to amend Roots charger design.