A three-Dimensional computational model is used to simulate flow in a non-axisymmetric, convergent-divergent nozzle incorporating porous cavities for shockboundary layer interaction control. The nozzle has an expansion ratio (exit area/throat area) of 1.797 and a design nozzle pressure ratio of 8.78. Flow fields for the baseline nozzle (no porosity) and for the nozzle with porous surfaces of 10...

Ejectors are known to be beneficial to vapor compression cycle performance as they can recover the kinetic energy released during the expansion instead of dissipating it in a throttling process. It is desirable to introduce an adjustable feature to the ejector so that ejector cycle performance can be optimized under different working conditions, which could make ejector technology more suitable...

one of the most common methods for controlling and increasing maneuverability of projectiles, especially the ones which move at high altitude and in low density air, is using lateral or reaction jets. the resultant force of the reaction jet is related to the jet and flow parameters. for finding their relation experimental, numerical, and analytical methods have been used. in order to change the...

We investigate the propagation of a premixed flame subject to thermal expansion through a narrow channel against a Poiseuille flow of large amplitude. This is the first study to consider the effect of a large-amplitude flow, characterised by a Péclet number of order one, Pe= O(1), on a variable-density premixed flame in the asymptotic limit of a narrow channel. It is also the first study on Tay...

We examine the effect of baseline nozzle shape on the ability of fan flow deflectors to reduce downward-emitted turbulent mixing noise of coaxial jets simulating the exhaust condition of a turbofan engine. Several deflector concepts were tested on a nozzle with parallel exit flow lines and a nozzle with convergent flow lines. In every comparison the nozzle with convergent flow lines produced su...

In this paper airflow, nano-and micro-particle motions in an aerodynamic particle beam focusing system consisting of several lenses, a nozzle and the downstream chamber, was studied. A three-dimensional numerical simulation for the system was presented and the compressible airflow and thermal conditions in the aerodynamic lens system were evaluated. Dilute particle concentration was assumed so ...

A quasi one-dimensional analysis of a STOVL aircraft nozzle in hover is performed to estimate the gross thrust coefficient as a function of nozzle pressure and nozzle area ratios. The analysis is supported by subscale, cold flow test results. The nozzle performance was found to be less than desirable in hover due to the overexpansion arising from the geometrical constraints of the existing nozzle.

Expansion work recovery by two-phase ejector is known to be beneficial to vapor compression cycle performance. However, one of the biggest challenges with ejector vapor compression cycle is that the ejector cycle performance is sensitive to working condition changes which are common in real world applications. Different working conditions require different ejector geometries to achieve maximum ...

A straightforward procedure has been developed to quickly determine an inviscid design of a hypersonic wind tunnel nozzle when the test gas is both calorically and thermally imperfect. This real gas procedure divides the nozzle into four distinct parts: subsonic, throat to conical, conical, and turning flow regions. The design process is greatly simplified by treating the imperfect gas effects ...

This paper presents the analysis of a two phase flow ejector for the transcritical CO2 cycle. A detailed simulation model of a two phase flow ejector was developed. A controllable ejector expansion device was designed, constructed, and installed in a transcritical CO2 experimental air conditioning system. System-level experimental results were obtained at different operation conditions and vari...