The use of different types of piston in an HCCI engine: A review

Abstract

Homogenous charge compression ignition (HCCI) combines the advantages of spark ignition (SI) and compression ignition (CI) engines to improve fuel consumption and emission levels. HCCI engines have the advantage of relatively higher engine efficiency than SI engines while maintaining lower emissions levels than CI engines. Combustion in HCCI engines occurs spontaneously at any location once the fuel-air mixture reaches its chemical activation energy. Pistons have a major effect on controlling the combustion inside the combustion chamber of an HCCI engine. Many researchers have studied various designs for pistons to improve HCCI engines. The aim of this study is to explore these different types of pistons and their designs in terms of improving the performance of HCCI engines fuelled with gasoline. The most common pistons used in HCCI are twostroke pistons, bowl types, specialised pistons, and dome-shaped pistons; each offers distinct advantages and disadvantages. Software simulation is the latest way of determining the best piston to be used for HCCI engines, as it is more cost effective and less time consuming than experiments. Overall, bowl type pistons offer reduced fuel consumption and a higher load capacity when used in an HCCI engine.

Geometry design and optimization of piston by using finite element method

“…Bowl piston has the lowest average temperature while dome piston has the highest average temperature. This is due to the more efficient combustion and faster burning rate of air-fuel mixture on bowl piston compared to dome piston [14]. Faster burning rate means that the air-fuel mixture is burned completely in a shorter amount of time.…”

“…After calculating the dimensions of the piston, the four types of piston head shapes are determined based on related studies. The four analyzed piston designs are flat-top piston, bowl piston, square bowl piston and dome piston since these piston designs are commonly used in the industries and they affect the combustion in cylinder differently which results in different deformation, temperature and stress distribution for different pistons [14]. All four piston designs are modelled using Solidworks based on the dimensions calculated.…”

A review on recent advances on improving polyimide matrix nanocomposites for mechanical, thermal, and tribological applications: Challenges and recommendations for future improvement

“…However, due to the high mechanical strength, good thermal stability, high stability under vacuum, good anti-radiation, better solvent resistance, and wear resistance behaviour of polyimide (PI) and its composites under certain conditions, have made the tribological scientists worldwide to show more extensive concern on polyimide based materials because of its properties. 44,73 Over the decades, thermoplastic polyimide as one of the high performance engineering polymers have received considerable attention due to its extraordinary performance when used as a material in mechanical moving parts of a space systems. Song et al 74 observed that space exploitation and development, demand high performance polymer based matrix tribo-materials for weight reduction purpose, which could also serve in improving the reliability of mechanical moving parts.…”

“…To enhanced the performances of polyimide nanocomposites for engineering applications, the incorporation of nanofillers, such as inorganic oxides (SiO 2 , Al 2 O 3 , TiO 2 , ZnO 2 , ZrO 2 ), carbon nanotubes (CNTs), graphene (GN), graphene oxide (GO), boron nitride (BN), molybdenum disulfide (MoS 2 ), ionic liquids (ILs), carbon fibres (CF), aramid fibre (AF), glass fibre (GF), silicon nitride (Si 2 N 4 ), and carbon nitride (C 3 N 4 ) into the polyimide matrix has widely been explored. However, the current review focuses on the recent 44 advances on the thermal, mechanical, and tribological properties of polyimide reinforced nanocomposites for tribological system, as well as it processing, challenges and recommendation for future improvement.…”

Huge Potential of HCCI Engine in Rarefied Air Environments

“…One of them is the challenge of incontrollable combustion phasing, in other words, an unpredictable ignition timing [1]. This profound consequence of instability is mainly the result of the compression ignition applied to the Air-fuel mixture: the premixed ratio could significantly affect the chemical reaction rate, even leading to a circumstance of multiple combustion stages [2]. Traditionally, on the Otto cycle, the spark plug is used for the ignition process, providing a convenient and tractable way of combustion phasing.…”