Engines equipped with camless valve trains will have greater space for performance optimization. In this paper, based on the electromagnetic actuated valve train system, one-dimensional and three-dimensional simulation models on engine thermodynamic cycle and in-cylinder charge motion are established, respectively. With the application of early-intake-valve closing (EIVC) strategy，unthrottled l...

The production of torque and pollutants of Variable Valve Actuation equipped internal combustion engines found in the automotive industry (both Diesel and gasoline engines) is studied. Variable Valve Actuation (VVA) is a technology which has been introduced to optimize engine efficiency at steady-states covering a wide range of operating conditions. In more details, the outcome of the internal ...

The production of torque and pollutants of Variable Valve Actuation equipped internal combustion engines found in the automotive industry (both Diesel and gasoline engines) is studied. Variable Valve Actuation (VVA) is a technology which has been introduced to optimize engine efficiency at steady-states covering a wide range of operating conditions. In more details, the outcome of the internal ...

Intake valve parameters significantly affect the performance of piston-type expander (PTE). To improve compressed energy utilization efficiency, intake need to be regulated according load. In this paper, an electro-pneumatic variable actuation (EPVVA) system was proposed for independent control distributing parameters. The trajectory planning obtain good mechanical properties. Then, duration an...

This paper presents a detailed model of a novel electropneumatic valve actuator for both engine intake and exhaust valves. The valve actuator’s main function is to provide variable valve timing and variable lift capabilities in an internal combustion engine. The pneumatic actuation is used to open the valve and the hydraulic latch mechanism is used to hold the valve open and to reduce valve sea...

INTRODUCTION VEHICLE engines have made remarkable progress since they first appeared and the operating range of engines in terms of rpm (revolutions per minute) and torque have expanded significantly. However, optimum engine design becomes difficult if the operation timing of the engine valves is fixed. For this reason, variable valve actuation has been used to optimize the valve timing in resp...

Due to environmental concerns, the recent regulation on automobile fuel economy has been strengthened. The market demand for efficient vehicles is growing and automakers to improve engine fuel efficiency in the industry have been paying a lot of effort. To improve the fuel efficiency, it is necessary to reduce losses or to improve combustion efficiency of the engine. VVA (Variable Valve Actuati...