Integrated Multi-Code Prediction of the Unsteady Flow Around Moving Valve and in Engine Intake Systems

2001 ◽  
Author(s):  
G. Chiatti ◽  
O. Chiavola
Keyword(s):  
Dynamic Response ◽  
Unsteady Flow ◽  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Design Procedure ◽  
Intake Port ◽  
Practical Relevance ◽  
Duct System ◽  
Gas Dynamic ◽  
Induction Process

Abstract Predictions of the behaviour of flow in duct system are of practical relevance in design procedure, since the performance of internal combustion engine critically depends on the gas dynamic response of the intake port and the cylinder during the induction process.

scholarly journals A Design of the Compression Chamber and Optimization of the Sealing of a Novel Rotary Internal Combustion Engine Using CFD

Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2362
Author(s):  
Savvas Savvakis ◽  
Dimitrios Mertzis ◽  
Elias Nassiopoulos ◽  
Zissis Samaras
Keyword(s):  
Internal Combustion Engine ◽  
Cfd Simulation ◽  
Combustion Engine ◽  
Numerical Study ◽  
Simulation Models ◽  
Internal Combustion ◽  
Intake Port ◽  
Significant Difference ◽  
Port Design ◽  
Compression Chamber

The current paper investigates two particular features of a novel rotary split engine. This internal combustion engine incorporates a number of positive advantages in comparison to conventional reciprocating piston engines. As a split engine, it is characterized by a significant difference between the expansion and compression ratios, the former being higher. The processes are decoupled and take place simultaneously, in different chambers and on the different sides of the rotating pistons. Initially, a brief description of the engine’s structure and operating principle is provided. Next, the configuration of the compression chamber and the sealing system are examined. The numerical study is conducted using CFD simulation models, with the relevant assumptions and boundary conditions. Two parameters of the compression chamber were studied, the intake port design (initial and optimized) and the sealing system size (short and long). The best option was found to be the combination of the optimized intake port design with the short seal, in order to keep the compression chamber as close as possible to the engine shaft. A more detailed study of the sealing system included different labyrinth geometries. It was found that the stepped labyrinth achieves the highest sealing efficiency.

Pseudo-Decoupling and Control of Unidentified Plant

1986 ◽  
Vol 108 (1) ◽  
pp. 74-79
Author(s):  
S. Thompson
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Design Procedure ◽  
Internal Combustion ◽  
Individual Basis ◽  
On Line ◽  
Diagonally Dominant ◽  
And Control ◽  
Step Responses

A procedure based on measured step responses, is presented for the pseudo-decoupling of basically linear, nonoscillatory, multivariable plant. The method generates pre- and post-compensator matrices that will tend to make an otherwise nondominant plant diagonally dominant. Once this is achieved, each loop is then tuned on an individual basis using one of the classical on-line methods, thus eliminating the need for a model. The method is illustrated by means of two examples. The first demonstrates the design procedure and the second reports on the application of the method in controlling the power generated by an internal combustion engine.

АКУСТИЧНА ПОМІТНІСТЬ БЕЗПІЛОТНИХ ЛІТАЛЬНИХ АПАРАТІВ З СИЛОВИМИ УСТАНОВКАМИ НА БАЗІ ПОРШНЕВИХ ДВИГУНІВ

2020 ◽  
pp. 62-80
Author(s):  
В. В. Руденко ◽  
И. В. Калужинов ◽  
Н. А. Андрущенко
Keyword(s):  
Control System ◽  
Internal Combustion Engine ◽  
Power Plants ◽  
Combustion Engine ◽  
Spectral Characteristics ◽  
Experimental Studies ◽  
Internal Combustion ◽  
Detection Range ◽  
Acoustic Signature ◽  
Static Conditions

The presence in operation of many prototypes of UAVs with propeller propellers, the use of such devices at relatively low altitudes and flight speeds makes the problem of noise reduction from UAVs urgent both from the point of view of acoustic imperceptibility and ecology.The aim of the work is to determine a set of methods that help to reduce the visibility of UAVs in the acoustic range. It is shown that the main source of noise from the UAV on the ground is the power plant, which includes the engine and the propeller. The parameters of the power plants influencing the processes that determine the acoustic signature of the UAV were investigated. A comprehensive analysis of the factors affecting visibility was carried out. The power plants include two-stroke and four-stroke engines, internal combustion and two-blade propellers. The use of silencers on the exhaust of the internal combustion engine was considered. The spectral characteristics of the acoustic fields of the propeller-driven power plants for the operating sample of the UAV "Eco" were obtained. The measurements were carried out in one-third octave and 1/48 octave frequency bands under static conditions. The venue is the KhAI airfield. Note that the propellers that were part of the power plants operated at Reynolds numbers (Re0,75<2*105), which can significantly affect its aerodynamic and acoustic characteristics. It is shown that when choosing a UAV control system, one should take into account the fact that two-stroke piston engines are the dominant source in the noise of propeller-driven control systems in the absence of a hood and mufflers in the intake and exhaust tracts. The use of a four-stroke internal combustion engine significantly reduces the noise of the control system. In the general case, the position of the boundaries of the zone of acoustic visibility of a UAV at the location of the observer is determined by the ratio between the intensity of acoustic radiation perceived by the observer from the UAV and the intensity of sound corresponding to the natural acoustic background and depends on the degree of manifestation of acoustic effects accompanying the propagation of sound in a turbulent atmosphere - the refraction of sound waves. Absorption and dissipation of acoustic energy. The calculation and comparison of the UAV detection range was carried out taking into account the existing natural maskers.The results of experimental studies are presented that allow assessing the degree of acoustic signature of the UAV. A set of measures aimed at reducing the intensity of the acoustic signature of the UAV in various regions of the radiation spectrum has been determined.

CONVERTING THE VEHICLE BY REPLACING THE INTERNAL COMBUSTION ENGINE

2019 ◽  
pp. 29-35
Author(s):  
Oleksandr Gryshchuk ◽  
Volodymyr Hladchenko ◽  
Uriy Overchenko
Keyword(s):  
Internal Combustion Engine ◽  
Electric Vehicle ◽  
Electric Motor ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Environmental Safety ◽  
Environmental Conservation ◽  
Sales Forecasts ◽  
Financial Investments ◽  
Near Future

This article looks at some comparative statistics on the development and use of electric vehicles (hereinafter referred to as EM) as an example of sales and future sales forecasts for EM in countries that focus on environmental conservation. Examples of financial investments already underway and to be made in the near future by the largest automakers in the development and distribution of EM in the world are given. Steps are taken to improve the environmental situation in countries (for example, the prohibition of entry into the city center), the scientific and applied problem of improving the energy efficiency and environmental safety of the operation of wheeled vehicles (hereinafter referred to as the CTE). The basic and more widespread schemes of conversion of the internal combustion engine car (hereinafter -ICE) to the electric motor car (by replacing the gasoline or diesel electric motor), as well as the main requirements that must be observed for the safe use and operation of the electric vehicle. The problem is solved by justifying the feasibility of re-equipment of the KTZ by replacing the internal combustion engine with an electric motor. On the basis of the statistics collected by the State Automobile Transit Research Institute on the number of issued conclusions of scientific and technical expertise regarding the approval of the possibility of conversion of a car with an internal combustion engine (gasoline or diesel) to a car with an electric motor (electric vehicle), the conclusions on the feasibility of such conclusion were made. Keywords: electricvehicles, ecological safety, electricmotor, statistics provided, car, vehicle by replacing.

Sign in / Sign up

Export Citation Format

Share Document