CFD Analysis of Charge Exchange in an Aircraft Opposed-Piston Diesel Engine

Abstract

The paper presents a description of geometric models, computational algorithms, and results of numerical analysis of charge exchange in an opposed-piston two-stroke engine. The research engine is a newly designed internal diesel engine. This unit is composed of three cylinders in which operate three pairs of opposed-pistons. The engine generates a power output equal to 100 kW at a crankshaft rotation speed of 3800-4000 rpm. The numerical investigations were carried out using ANSYS FLUENT solver. The geometrical model includes an intake manifold, a cylinder and an outlet manifold. The study was conducted for a series of modifications of manifolds and intake and exhaust ports to optimise the charge exchange process in the engine. In addition, we attempted to verify the effect of the combustion chamber shape on the charge exchange process in the engine. The calculations specified a swirl coefficient obtained under steady conditions for fully open intake and exhaust ports as well as the CA value of 280° for all cylinders. In addition, mass flow rates were identified separately in all of the intake and exhaust ports to achieve the best possible uniformity of flow in particular cylinders. The paper includes comparative analyses of all of the intake and exhaust manifolds of the designed engine.

An investigation of the fuel injector dedicated to the aircraft opposed-piston two-stroke diesel engine

“…The investigations of fuel jet penetration were carried out in a constant volume chamber with the following parameters: maximum working pressure of 15 MPa, optical access in the shape of a circle with a diameter of 160 mm, volume of about 5.5 dm 3 . A piezoelectric Kistler sensor (0-25 MPa) measured the pressure in the chamber, while a piezoresistive Kistler sensor (0-200 MPa) measured the fuel pressure.…”

“…The engine will generate a power output equal to 100 kW at a crankshaft rotation speed of 3800-4000 rpm, with a capacity of about 1.6 l, with a Diesel cycle. The engine will be equipped with a direct Diesel injection system [3]. It was assumed initially that the chamber to test fuel spray in the engine injection analysis should maintain nitrogen or air pressure at the level of P pow = 5-8 MPa.…”

Wind Tunnel Research on the Unmanned Aerial Vehicle Rotor Blade Setting Angle

“…Despite the fact that internal combustion engines are displaced by hybrid solutions in the automotive industry, new or improved propulsion systems, e.g. Diesel engines [4], SI engines [10,11] or Wankel engines [27] are still being tested in aviation. Furthermore, the publication [3] presents the results of research on the optimization of the wing and blade structures with active elements.…”

Modelling of Dynamic Interactions in the Fuel Rail for the Aircraft Diesel Engine

“…Research is carried out all over the world on this type of constructions, among others by [15,16,18]. For example, the ways of cooling these engines by [6] are analyzed, which is a key issue in this type of construction.…”