In this paper the jet model for the supermassive black hole candidate Sgr A* in the Center of the Galaxy is reviewed. The most recent model, with a reduced set of parameters, is able to account for all major radio properties of the source: size, structure, ux density, and spectrum. The model requires a minimum jet power of 10 39 erg/sec and in a symbiotic jet/disk system implies a minimum accre...

The circular-hole rotating core fog nozzle has excellent atomization performance and been widely used in the realm of spray dust. As part this study, a mathematical model was developed for predicting Sauter mean diameter (SMD) nozzles type. coaction between SMD three influencing factors axial distance, water supply pressure, outlet investigated based on customized spray’s experimental platform ...

Research on renewable and alternative fuels is crucial for improving the energy environmental efficiency of modern gasoline internal combustion engines. To highlight influence fuel rheological thermodynamic properties phase change atomisation processes, three types blends were tested. More specifically, campaign comprised a reference gasoline, an ethanol/gasoline blend (10% v/v) representative ...

Dynamics of in-nozzle flow are known to have crucial impacts on the spray structure, and thus hole-to-hole variation in transient cavitating is strongly suspected being a source undesirable asymmetries. This study focuses effects needle motion evolution cavitation regimes. For verifying numerical models, simulation results obtained using Winklhofer throttle “U” real-size two-hole optical nozzle...

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...

In this paper a numerical approach for the prediction of the unsteady atomization process of liquid fuel in Diesel engine is presented. The dependences between the transient nozzle flow and spray formation are analysed. For that purpose models to simulate unsteady nozzle flows including the transient behaviour of cavitation and two-phase atomization process are employed. Results of transient fl...

Lateral nozzle forces are known to cause severe structural damage to any new rocket engine in development. Currently there is no fully coupled computational tool to analyze this fluid/structure interaction process. The objective of this study was to develop a fully coupled aeroelastic modeling capability to describe the fluid/structure interaction process during the transient nozzle operations....

The objective of this research was to develop advanced diesel combustion strategies for emissions reduction in a multi-cylinder diesel engine. The engine was equipped with an electronically-controlled, common-rail fuel injection system, and an exhaust gas recirculation (EGR) system. This experimental setup allowed a wide range of operating conditions to be explored. Effects of various injector ...