...S. Adnan Qasim; M. Afzaal Malik; M. Ali Khan; R. A. Mufti A fully established elastohydrodynamic lubricating (EHL) film between the piston and the liner surfaces during normal engine operation minimizes piston slap and prevents adhesive wear. Wear cannot be prevented in the initial engine start up...

...Yves Bidaut; Urs Baumann This paper focuses on the casing geometry of high pressure compressors. It is common practice to use damper seals, typically the hole pattern type, at the balance piston to ensure the stability of the compressor when compressing fluids with high density levels. Special...

... injection mainly acts to enhance stability by changing the flow field of the division wall or balance piston seals, not by influencing the back-shroud’s forces or moments. Effective swirl brakes at these seals also serve this purpose. Equations 15 , 19 define the inlet circumferential perturbation...

...Kukwon Cho; Ronald O. Grover, Jr.; Dennis Assanis; Zoran Filipi; Gerald Szekely; Paul Najt; Rod Rask A two-pronged experimental and computational study was conducted to explore the formation, transport, and vaporization of a wall film located at the piston surface within a four-valve, pent-roof...

...Moussa Diaby; Michel Sablier; Anthony Le Negrate; Mehdi El Fassi On the basis of ongoing research conducted on the clarification of processes responsible for lubricant degradation in the environment of piston grooves in exhaust gas recirculation (EGR) diesel engines, an experimental investigation...

...A. Beccari; S. Beccari; E. Pipitone It is well known that the spark advance is one of the most important parameters influencing the efficiency of a spark ignition engine. A change in this parameter causes a shift in the combustion phase, whose optimal position, with respect to the piston motion...

... ), to the numerical analysis of flow fields in a test engine with flat-piston and bowl-in-piston arrangements, under swirling and no-swirling flow motored conditions. The model capabilities in capturing turbulent flow features were compared to those of the upgraded linear RNG k - ε model, which was previously...

...E. Abu-Nada; I. Al-Hinti; A. Al-Sarkhi; B. Akash This paper presents thermodynamic analysis of piston friction in spark-ignition internal combustion engines. The general effect of piston friction on engine performance was examined during cold starting and normal working conditions. Considerations...

... a moving piston and the kinetics of combustion and pollutant production—quickly becomes considerable in terms of simulation time requirements. One limiting factor is the modeling of the small length scales of the poppet valve flow. Such length scales can be three orders of magnitude smaller than cylinder...

...), and Colorado State University (CSU). This project is part of the Advanced Reciprocating Engine System (ARES) program led by the U.S. Department of Energy. Previous papers have discussed the computational tools used to evaluate piston-ring/cylinder friction and described the effects of changing various ring...

...Tongxun Yi; Ephraim J. Gutmark The present paper performs complementary experimental and theoretical investigations of a pump-style, high-frequency, magnetostrictive fuel actuator, which achieves fuel modulations by periodically “pushing” fuel out of a piston-cylinder unit instead of by modulating...

... is an essential element of the operation of the engine. Using linearized theory, the pressure in the compression and expansion spaces is found as a function of the ratio of piston amplitudes and piston phase difference. The regenerator is taken to be thermally perfect. All variations are taken to be sinusoidal...

... from both engine operating phases was investigated. Relatively higher concentrations of all wear metals were found in the lubricating oil of the EGR-operated engine, which indicates higher wear of various engine parts. Weight loss of piston rings used in both phases was compared to quantify the amount...

... and related emission sources. Although a variety of turbulence models has long been proposed, the assessment of even the most widely used k - ε model is still lacking, especially for bowl-in-piston engines. This paper provides a survey of k - ε turbulence model variants and their numerical implementation...

...Shyy Woei Chang; Yao Zheng This paper describes an experimental study of heat transfer in a reciprocating planar curved tube that simulates a cooling passage in piston. The coupled inertial, centrifugal, and reciprocating forces in the reciprocating curved tube interact with buoyancy to exhibit...

...Yasuo Harigaya; Michiyoshi Suzuki; Fujio Toda; Masaaki Takiguchi The effect of lubricant viscosity on the temperature and thickness of oil film on a piston ring in a diesel engine was analyzed by using unsteady state thermohydrodynamic lubrication analysis, i.e., Reynolds equation and an unsteady...