Nozzle

About: Nozzle is a research topic. Over the lifetime, 158675 publications have been published within this topic receiving 893026 citations. The topic is also known as: spout.

Reactant gas ejector head

Abstract: A reactant gas ejector head enables a process gas mixture of a uniform concentration and composition to be delivered to the surface of a substrate in a stable and uniform thermodynamic state by preventing premature reactions to occur along the gas delivery route. The reactant gas ejector head comprises an ejection head body having a back plate and a nozzle plate for defining a gas mixing space therebetween. The nozzle plate has numerous gas ejection nozzles. A gas supply pipe is communicated with the ejection head body through a center region of the back plate so as to separately introduce at least two types of gaseous substances into the mixing space. Gas distribution passages are formed between the back plate and the nozzle plate in such a way as to guide the at least two types of gaseous substances from the gas supply pipe to be directed separately towards peripheral regions of the gas mixing space.

Far-Field Acoustic Investigation into Chevron Nozzle Mechanisms and Trends

Abstract: Chevron nozzles currently offer one of the most feasible methods of reducing jet exhaust noise in medium to high-bypass turbofan engines. Tests were conducted in the University of Cincinnati Nozzle Acoustic Test Facility, simulating a separate flow exhaust system to provide insight into some of the basic mechanisms and trends of this emerging technology. For this study, a baseline inner nozzle and three chevron nozzles were tested over a wide range of operating conditions, including dual and single flow. Chevrons with varying numbers of lobes and levels of penetration were selected for this study to provide insight into the impact of these geometric parameters on the noise level. Spectral and directivity results from heated, coaxial flow tests showed that the chevron nozzles are most effective at lower frequencies and at aft directivity angles. Reductions in overall sound pressure level (SPL) ranging from 3 to 6 dB were documented. Calculations of perceived noise level directivity also showed 4-6 dB reduction at aft angles. The data also illustrated clear and consistent trends with respect to the chevron geometric parameters. Specifically, the chevron penetration was determined to be a primary factor in controlling the tradeoff between low-frequency reduction and high-frequency SPL increases. Although slight differences were observed with varying chevron lobe numbers at a fixed penetration, it appears that the effect is less significant than the penetration. Finally, the data indicated clear dependence of the chevron benefit on the velocity difference between the inner and outer streams.

Preventing apparatus for freezing of fountain nozzle

Abstract: PURPOSE: To prevent the freezing of fountain nozzle, by arranging one end of a heat pipe in the periphery of a nozzle case, and by allowing the other end to contact with a heat source. CONSTITUTION: When a fountain is stopped, fall of the open air temp. lowers the temp. of hydraulic fluid vapor in the heat pipe 21. When the temp. of the hydraulic fluid is lowered to a temp. not higher than that of soil, the part 21b, which is laid in the soil, of the heat pipe 21 is heated, and the hydraulic fluid is evaporated by the heat of the soil and flows to the other end 21a which is in contact with the nozzle case 1. At that time, the fluid vapor condenses to form liquid because the nozzle case is at a lower temp. than the soil, at the same time it releases condensing heat to the nozzle case 1. The condensed hydraulic fluid penetrates into a capillary material and is refluxed to the part 21b in the soil. Said circulation of the hydraulic fluid allows to heat the water contained in the nozzle case 1 with the heat held in the soil. Utilization of a main water pipe 4 as a heat source exerts the same effect. COPYRIGHT: (C)1981,JPO&Japio