A theoretical study analyzing three-dimensional combustion acoustic instabilities in a liquid propellant rocket engine combustor has been conducted. A linear theory based on Crocco’s pressure sensitive time lag model is used. To apply this theory the combustor is divided into two main components, including the combustion chamber and the converging part of the nozzle. The assumption of concentra...

A high-speed gas flow, generated by a miniature supersonic nozzle for microparticle acceleration, is investigated. In medical application, the powder formulation of drugs can be delivered into human skin or mucosal tissue for the treatment of a range of diseases. One of the main concerns for designing and evaluating such system is ensuing that microparticles are delivered into human skin with a...

Abstract—There is a gap at combustor-turbine interface where leakage flow comes out to prevent hot gas ingestion into the gas turbine nozzle platform. The leakage flow protects the nozzle endwall surface from the hot gas coming from combustor exit. For controlling flow’s stream, the gap’s geometry is transformed by changing fillet radius size. During the operation, step configuration is occurre...

Natural gas flow contains undesirable solid particles, liquid condensation, and/or oil droplets and requires reliable removing equipment to perform filtration. Recent natural gas processing applications are demanded compactness and reliability of process equipment. Since conventional means are sophisticated in design, poor in efficiency, and continue lacking robust, a supersonic nozzle has been...

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...

Laser machining efficiency and quality are closely related to gas pressure, nozzle geometry, and standoff distance. Modeling studies of laser machining rarely incorporate gas effects in part because of the complex structure and turbulent nature of jet flow. In this paper, the interaction of a supersonic, turbulent axisymmetric jet with the workpiece is studied. Numerical simulations are carried...

Cooling characteristics are given in terms of the variation of average blade temperature at mid-span with cooling-flow rate, Reynolds number, gas/cooling-air absolute temperature ratio, and, for the rotor, gas-stream incidence. Chordwise and spanwise variations of blade temperature are also presented. Measured pressure-drop characteristics indicate that in a gas-turbine engine, with the cooling...

A system for cold ow testing of an aerospike nozzle has been developed in an e ort to examine the e ectiveness of aerodynamic thrust vectoring and truncated nozzle base bleed. These tests are designed to produce results that will support the design of a system for hot ow testing of the same technologies. Design of a nozzle suitable for testing with reasonable cold-gas mass ow rates and measurea...

C i c ^ A one-dimensional theory based upon fundamental flow relationships ^ is presented for analyzing the behavior of one or more gas streams flowing MM through a single nozzle. This conpound-coropressible flow theory shows that f^ the behavior of each stream is influenced by the presence of the other ^^ streams. The theory also shows that the behavior of coiTpound--coiTpressible flow is pred...

Planar laser-induced fluorescence visualisation isused to investigate nonuniformities in the flow of a hyper-sonic conical nozzle. Possible causes for the nonuniformityare outlined and investigated, and the problem is shown to bedue to a small step at the nozzle throat. Entrainment of coldboundary layer gas is postulated as the cause of the signalnonuniformity.