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Chamber pressure

About: Chamber pressure is a research topic. Over the lifetime, 2988 publications have been published within this topic receiving 30725 citations.


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Patent
18 Jun 1990
TL;DR: In this paper, the authors describe a mechanism comprising a dynamic seal having 120,122 components having cooperating movable surfaces for sealing a treatment chamber that substantially prevents the passage of fluid at the treatment chamber pressure during movement of the components.
Abstract: Process and apparatus for the treatment of tobacco material and other biological materials includes a mechanism comprising a dynamic seal having components (120,122) having cooperating movable surfaces for sealing a treatment chamber (50) that substantially prevents the passage of fluid at the treatment chamber pressure during movement of the components for introducing material into and removing material from the chamber. The seal components preferably comprise advanced structural ceramic components having a hardness of at least 900 kg/mm² and a flatness of at least 70 microinches (1.8 micrometres). The process is preferably conducted at supercritical gaseous conditions.

11 citations

Journal ArticleDOI
Michael Flouros1
TL;DR: In this paper, a parametric study on the bearing power consumption has been performed with a 124 mm pitch circle diameter (PCD) ball bearing in a bearing chamber that has been adapted from the RB199 turbofan engine.
Abstract: Trends in aircraft engines have dictated high speed rolling element bearings up to 3 million DN or more with the consequence of having high amounts of heat rejection in the bearing chambers and high oil scavenge temperatures. A parametric study on the bearing power consumption has been performed with a 124 mm pitch circle diameter (PCD) ball bearing in a bearing chamber that has been adapted from the RB199 turbofan engine (DN∼2 × 10 6 ) The operating parameters such as oil flow, oil temperature, sealing air flow, bearing chamber pressure, and shaft speed have been varied in order to assess the impact on the power consumption. This work is the first part of a survey aiming to reduce power losses in bearing chambers. In the first part, the parameters affecting the power losses are identified and evaluated.

11 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of gas generator pressure on the physicochemical, oxidation and combustion characteristics of the condensed primary combustion products of boron-based propellants was investigated by energy-dispersive (EDS), X-ray photoelectron spectroscopy and scanning electron microscopy with energydispersively (SEM-EDS) individually.
Abstract: To clarify the effect of gas generator pressure on the physicochemical, oxidation and combustion characteristics of the condensed primary combustion products of boron-based propellants, the elemental, composition and morphology of the primary combustion products collected under chamber pressure of 0.2–8 MPa were investigated by energy-dispersive (EDS), X-ray photoelectron spectroscopy and scanning electron microscopy with energy-dispersive (SEM–EDS) individually. The oxidation, ignition and combustion behaviors of these products were further studied by laser ignition system and thermogravimetry–differential scanning calorimetry. We found out that high-pressure condition lowered the content of elementary boron and elementary carbon while raised the content of boron carbide. Numerous spherical carbon particles with a diameter around 100 nm were observed in the products. Boron lumps were partially or almost fully covered with carbon particles on the surface. The reaction mechanisms of thermal oxidation of primary combustion products were given. The onset temperature of boron in the products kept at 500 °C when pressure ranged from 3 to 8 MPa but increased to 583 °C at 0.2 MPa. As the pressure increased from 0.2 to 8 MPa, the emission spectrum intensity of both boron and carbon got enhanced by ~25%, and the ignition delay of boron was significantly shortened by 515 ms. In conclusion, high gas generator pressure is favorable to the secondary ignition and combustion of primary combustion products.

11 citations

Journal ArticleDOI
TL;DR: In this article, it was shown that reduction of the primary exhaust velocity to subsonic speed significantly improves the ignition process of the gaseous components and the boron particle combustion efficiency.
Abstract: Theme I ducted rockets using boron-loaded solid propellants, primary chamber reaction products containing unreacted gaseous and particulate fuels mix, ignite, and burn with a subsonic airstream in a secondary chamber. It is generally known that the overall efficiency of these systems decreases with decreasing secondary chamber pressure, increasing air-to-fuel ratio, and decreasing propellant mass flow. Based on systematic tests in a subscale rocket motor,' it was determined that ignition of the gaseous fuel components of the primary chamber with the airstream is critical if high combustion efficiency of the boron components is to be achieved. This study provides additional insight into the ignition and combustion processes of the gaseous components with and without boron particles. It will be shown that reduction of the primary exhaust velocity to subsonic speed significantly improves the ignition process of the gaseous components and the boron particle combustion efficiency.

11 citations

Patent
17 Apr 1996
TL;DR: In this article, the authors present a method for producing an enhanced adsorbent and/or enhanced catalytic particle, comprising the steps of: (a) removing an effective amount of air from a closed chamber containing an ad-orbent or catalytic particles, wherein the resultant chamber pressure is less than one atmosphere; (b) raising the chamber pressure with an inert gas to at least one atmosphere, and (c) contacting the particle with an energy beam of sufficient energy for a sufficient time to thereby enhance the adsorbents or catalysts.
Abstract: A method for producing an enhanced adsorbent and/or enhanced catalytic particle and/or for producing a catalytic particle, comprising the steps of: (a) removing an effective amount of air from a closed chamber containing an adsorbent and/or catalytic particle, wherein the resultant chamber pressure is less than one atmosphere; (b) raising the chamber pressure with an inert gas to at least one atmosphere; (c) contacting the particle with an energy beam of sufficient energy for a sufficient time to thereby enhance the adsorbent and/or catalytic properties of the particle and/or produce catalytic properties in the particle. A continuous process directed to step (c) alone is also provided. Also disclosed are adsorbent and/or catalytic particles, methods of contaminant reduction or elimination, including room temperature catalysis, particle binders, apparatuses of the present invention, and methods of increasing the surface area of adsorbent and/or catalytic particles.

11 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202322
202257
202167
202086
201991
201882