Showing papers on "Dynamic pressure published in 1976"

Gravity Waves Propagated over Permeable Bottom

Abstract: Based on Forchheimer equation and potential theory, the propagation of small amplitude surface waves over a permeable bed is examined. The special linearization technique that is based on the assumption of the equivalent work (Lorentz' hypothesis) is employed in order to determine analytically the velocity field and pressure field. Demanding the continuity of pressure and velocity components at the interface, the damping factor and wave number for arbitrary permeability are found. The example calculations show that the influence of the permeability on the pressure distribution is negligibly small.

Turbocompound engine with turbocharger control

Abstract: An exhaust energy extraction system for a multi-cylinder engine, comprisingn axial flow turbine arranged to convert time-spaced exhaust pressure pulses into turbine rotor rotation. Output flow from the axial flow turbine is directed through a diffuser that converts velocity pressure to static pressure; a second radial flow turbine is operated by the steady state flow produced by the diffuser. Any tendency of the diffuser to exert an adverse back pressure on the axial flow turbine is counteracted by a pressure-responsive vent valve that establishes a ceiling on the diffuser pressure.

Static and dynamic pressure measurement - is of gaseous or fluid substances of high electric potential and uses pressure measurement box

Abstract: The pressure measurement box is at the potential of the substance to the measured and the indicator at the potential of the earth. An insulating line connects the pressure measuring box and indicator. A metal-coated diaphragm (2) under pressure in the pressure measuring box (1) is exposed to an amplitude stabilised light beam (3). The pressure dependent part (4) of the light beam (3) reflected by the diaphragm (2) is absorbed by a light sensitive element and measured in the indicating device (7). The stabilised light beam passes via electrically insulated light guides (5, 6) between the pressuring box (1) and indicating device (7).

Inelastic response of ring-stiffened cylindrical shells to external pressure shock waves

Abstract: : An incremental finite-differences approach based on an absolute minimum principle in dynamic finite plasticity is developed to study the inelastic response of ring-stiffened cylindrical shells to underwater explosions. The pressure in the shock wave caused by an underwater explosion is treated as a prescribed transient load acting on a shell. Numerical results for five cases are presented. The results indicate that dynamic stress concentrations and yielding occur in the shell near the ring stiffeners or other hard points.

Oil well differential pressure recorder - for small pressure changes by clockwork controlling valve opening and pen rotation

Abstract: A recorder for differential pressures in oil wells includes a bottom end with a labyrinth and a cylindrical bush which encloses a spiral spring in the bottom chamber. The latter rests through a thrust bearing on a piston. The piston is revolved through a fork from a clockwork in a separate housing and carriers rollers with a pen for a chart paper. The piston can be moved axially by the differential pressure between a recording chamber and the bottom chamber. This records even slight pressure changes in the well accurately and reliably. A simple change of the spiral spring makes the recorder suitable for a wide pressure range. Rising and falling pressure changes are covered and a precise knowledge of the dynamic pressure in the well is not necessary.

Calibration method and device of vibrationnpressure pickup

Abstract: PURPOSE:In order to calibrate the dynamic pressure with high frequency and small amplitude in such space like a rocket combustion chamber and so on, basing on the calibrated value being obtained from the static pickup and Basic Differential-Pressure Gauge

Compressor Stator Time-Variant Aerodynamic Response to Upstream Rotor Wakes.

Abstract: : An experimental investigation was conducted to determine the fluctuating pressure distribution on a stationary vane row, with the primary source of excitation being the wakes from the upstream rotor blades. This was accomplished in a large scale, low speed, single stage research compressor. The forcing function, the velocity defect created by the rotor wakes, was measured with a crossed hot-wire probe. The aerodynamic response on the vanes was measured by means of flush mounted high response dynamic pressure transducers. The dynamic data were analyzed to determine the chordwise distribution of the dynamic pressure coefficient and aerodynamic phase lag as referenced to a transverse gust at the vane leading edge.