The objective of this study is to investigate the thermal efficiency and power production of typical models of endoreversible heat engines at the regime of minimum entropy generation rate. The study considers the Curzon-Ahlborn engine, the Novikov's engine, and the Carnot vapor cycle. The operational regimes at maximum thermal efficiency, maximum power output and minimum entropy production rate...

investigations were carried out to evaluate the performance of direct injection diesel engine with medium grade low heat rejection (lhr) combustion chamber and 3 mm air gap insulated piston, 3 mm air gap insulated liner, and ceramic coated cylinder head [ceramic coating with the thickness of 500 µ was made on the inside portion of the cylinder head].the engine had different operating conditions...

In order to comply with stringent pollutant emissions regulations, a detailed analysis of the engine combustion and emission is required. In this field, computational tools like CFD and engine cycle simulation play a fundamental role. Therefore, the goal of the present work is to simulate a high speed DI diesel engine and study the combustion and major diesel engine emissions with more deta...

A simple urn model is presented that may describe heat engines employing as working agents spin2 particles (e.g., electrons) or twolevel atoms. In this model the cold reservoir is an urn located at altitude ǫc that contains N balls of total weight nc. Likewise, the hot reservoir at altitude ǫh contains N balls of total weight nh. A cycle consists of exchanging two randomly selected balls betwee...

Stochastic heat engines are devices that generate work from random thermal motion using a small number of highly fluctuating degrees of freedom. Proposals for such devices have existed for more than a century and include the Maxwell demon and the Feynman ratchet. Only recently have they been demonstrated experimentally, using, e.g., thermal cycles implemented in optical traps. However, recent e...

designing and optimization of the intake manifold is one of the important steps in the development of the internal combustion engines. in this paper, the flow inside the intake manifold of an internal combustion engine is investigated by numerical modeling. the convective flux models are adopted to simulate the unsteady compressible flow behavior. to solve the governing equations, for calculati...

We analyze the experimental time series of internal pressure in a four cylinder spark ignition engine. In our experiment, performed for different spark advance angles, apart from the usual cyclic changes of engine pressure we observed additional oscillations. These oscillations are with longer time scales ranging from one to several hundred engine cycles depending on engine working conditions. ...

This paper deals with the performance and emission analysis of a multicylinder diesel engine using biodiesel along with an in-depth analysis of the engine heat losses in different subsystems followed by the energy balance of all the energy flows from the engine. Energy balance analysis allows the designer to appraise the internal energy variations of a thermodynamic system as a function of ''en...