Chamber pressure

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

The Experimental Investigation of Effects of Multiple Parameters on the Formability of the DC01 Sheet Metal

Abstract: The formability of sheet metal materials through the deep drawing process is affected by various parameters, such as die chamber pressure, die radius and sheet thickness, all of which directly influence the product’s quality. This paper investigates the formability of the DC01 sheet metal material. DC01 is a carbon steel sheet, which has a wide range of usages from the automotive industry to the manufacture of radiators by means of hydro-mechanical and conventional deep deep drawing methods. This study, for the first time, empirically investigates the effects of die chamber pressure, die radius and sheet thickness on the formability of DC01 sheet metal material through hydro-mechanical and conventional deep deep drawing methods. The study also helps to determine the forming parameters for this material. With regard to the hydro-mechanical deep drawing process, the drawing ratio increased from 2.16 to 2.33, solely due to an increase in die chamber pressure. The results of the experiment revealed suitable forming parameters through hydro-mechanical and conventional deep drawing methods for samples of DC01 material having a cylindrical geometry.

Properties of a new organo silver compound for mocvd

Abstract: Trans-bis(trimethylsilyl)ethene(1,1,1,5,5,5-hexafluoro-2,4-pentanedionato)Ag(I), (BTMSE)Ag(hfac) was found to be a very promising compound for CVD Ag wiring. It is a solid at r.t. (m.p. 70°C), has a vapor pressure (10−3 Torr at r.t.) and high thermal stability, and can be used as a precursor for MOCVD. Thermal and laser CVD silver films were grown on TiN Si(100) from (BTMSE)Ag(hfac) in a quartz vacuum chamber, using thermal activation by an electric heater or photo activation through a quartz window with an excimer laser (XeCl, 308 nm). The chamber pressure was varied from 2 to 30 Torr. The evaporation temperature was kept at 80°C. Ar gas was used as the carrier with a flow rate in the evaporation cylinder varying from 50 to 200 ccm. A growth rate of 3 nm/min was achieved at 200°C, an evaporation temperature of 80°C, an argon flow rate of 100 ccm and a chamber pressure of 10 Torr. Resistivities were of the order of about 10−3 cm depending on the film morphology. With laser CVD, a growth rate of 3 nm/min was achieved by laser activation at 80°C, an evaporation temperature of 120°C, an argon flow rate of 100 ccm and a chamber pressure of 10 Torr. Resistivities were of the order of about 10−6 Ω cm depending on the film morphology. The laser CVD results were far better than the thermal CVD ones. The film morphology was finer and more evenly distributed with a faster growth rate at much lower temperatures.

Rotary compressor with discharge chamber pressure relief groove

Abstract: The annular piston of a rolling piston compressor coacts with a groove in valving action such that the groove serves as a supplemental discharge flow area but gas therein is prevented from constituting part of the suction flow. The groove may be in the motor end bearing and/or pump end bearing and permits flow from the compression chamber to the interior of the piston which is in fluid communication with the interior of the shell while the compression chamber is undergoing discharge.

Conceptual Design for a Kerosene Fuel-rich Gas-generator of a Turbopump-fed Liquid Rocket Engine

Abstract: A design method for a kerosene fuel-rich gas-generator of a liquid rocket engine using turbopumps to supply propellant was performed at a conceptual level. The gas-generator creates hot gases, enabling the turbine to operate the turbopumps. A chemical non-equilibrium analysis and a droplet vaporization model were used for the estimation of the burnt gas properties and characteristic chamber length. A premixed counter-flow flame analysis was performed for the prediction of the burnt gas properties, namely the temperature, the specific heat ratio and heat capacity, and the chemical reaction time. To predict the vaporization time, the Spalding model, using a single droplet in convective condition, was used. The minimum residence time in the chamber and the characteristic length were calculated by adding the reaction time and the vaporization time. Using the characteristic length, the design methods for the fuel-rich gas-generator were established. Finally, a parametric study was achieved for the effects of the O/F ratio, mass flow rate, chamber pressure, initial droplet temperature, initial droplet diameter and initial droplet velocity.

Hydraulic power brake unit

Abstract: A hydraulic power brake unit including a power piston operatively engaging a conventional master cylinder and an annular valve spool having differential end areas communicating with the power chamber formed by the power piston and being normally positioned in the housing to communicate hydraulic fluid from a pressure source to the power steering unit and communicate the power chamber to the power source reservoir. When the brake pedal is actuated, an actuating spring acting between the valve spool and a reaction piston attached to the pedal pushrod is compressed and the valve spool is moved to restrict fluid communication from the pressure source to the power steering unit and divert the flow to the power chamber while simultaneously blocking communication of the power chamber to the reservoir so that the power chamber is pressurized and the power piston fluidly displaced to actuate the master cylinder. The power chamber pressure acts on the differential area of the valve spool to resist its movement by the actuating spring and causes it to function as a regulating valve which continuously provides a power chamber pressure proportional to the force of the actuating spring. Upon a malfunction caused loss of hydraulic pressure the reaction piston moves into abutting engagement with the power piston to provide a rigid force transmitting link between the pushrod and the master cylinder whereby the brakes are actuated independently of the hydraulic boost.