scholarly journals On the Pressure Dependency of the Bagley Correction

2013 ◽  
Vol 28 (5) ◽  
pp. 558-564 ◽  
Author(s):  
P. Van Puyvelde ◽  
A. Vananroye ◽  
A.-S. Hanot ◽  
M. Dees ◽  
M. Mangnus ◽  
...  
Keyword(s):  
Pressure Dependency ◽  
Bagley Correction

Improvement and validation of a physically based model for the shear and transverse crushing of orthotropic composites

2018 ◽  
Vol 53 (12) ◽  
pp. 1681-1696 ◽  
Author(s):  
Sérgio Costa ◽  
Thomas Bru ◽  
Robin Olsson ◽  
André Portugal
Keyword(s):  
Current Model ◽  
Three Dimensional ◽  
Fracture Plane ◽  
Damage Growth ◽  
Pressure Dependency ◽  
Orthotropic Composites ◽  
Fabric Composites ◽  
Final Failure ◽  
Physically Based ◽  
Nonlinear Shear

This paper details a complete crush model for composite materials with focus on shear dominated crushing under a three-dimensional stress state. The damage evolution laws and final failure strain conditions are based on data extracted from shear experiments. The main advantages of the current model include the following: no need to measure the fracture toughness in shear and transverse compression, mesh objectivity without the need for a regular mesh and finite element characteristic length, a pressure dependency of the nonlinear shear response, accounting for load reversal and some orthotropic effects (making the model suitable for noncrimp fabric composites). The model is validated against a range of relevant experiments, namely a through-the-thickness compression specimen and a flat crush coupon with the fibres oriented at 45° and 90° to the load. Damage growth mechanisms, orientation of the fracture plane, nonlinear evolution of Poisson's ratio and energy absorption are accurately predicted.

Pressure dependency for heavy isotope enhancement in ozone formation

1990 ◽  
Vol 17 (6) ◽  
pp. 717-719 ◽  
Author(s):  
Mark H. Thiemens ◽  
Teresa Jackson
Keyword(s):  
Ozone Formation ◽  
Heavy Isotope ◽  
Pressure Dependency

The effect of pressure on thermal diffusivity in pyroxenes

2011 ◽  
Vol 75 (5) ◽  
pp. 2597-2610 ◽  
Author(s):  
S. A. Hunt ◽  
A. M. Walker ◽  
R. J. McCormack ◽  
D. P. Dobson ◽  
A. S. Wills ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Harmonic Oscillator ◽  
Data Sets ◽  
Damped Harmonic Oscillator ◽  
Polynomial Fit ◽  
Pressure Dependency ◽  
Harmonic Oscillator Model ◽  
Order Polynomial ◽  
Subducting Slab

AbstractThe thermal diffusivity of diopside, jadeite and enstatite were measured at simultaneous pressures and temperatures of up to 7 GPa and 1200 K using the X-radiographic Ångström method. The measurements herein show that the pressure dependency of thermal diffusivity in pyroxenes is significantly greater than in olivine or garnet and that in the MORB-layer of a subducting slab the thermal diffusivity of pyroxenes are a factor of 1.5 greater than that of olivine. The temperature dependence of all the data sets is well described by a low-order polynomial fit to 1/K and the pressure dependence is exponential in 1/K, formulations which are consistent with the damped harmonic oscillator model for thermal properties.

scholarly journals Testing and evaluation of a new airborne system for continuous N<sub>2</sub>O, CO<sub>2</sub>, CO, and H<sub>2</sub>O measurements: the Frequent Calibration High-performance Airborne Observation System (FCHAOS)

2018 ◽  
Vol 11 (11) ◽  
pp. 6059-6074 ◽  
Author(s):  
Alexander Gvakharia ◽  
Eric A. Kort ◽  
Mackenzie L. Smith ◽  
Stephen Conley
Keyword(s):  
High Frequency ◽  
High Performance ◽  
Continuous Wave ◽  
Spatial Scales ◽  
Observation System ◽  
N2o Emissions ◽  
Flight System ◽  
Pressure Dependency ◽  
Calibration Methods ◽  
Ambient Concentration

Abstract. We present the development and assessment of a new flight system that uses a commercially available continuous-wave, tunable infrared laser direct absorption spectrometer to measure N2O, CO2, CO, and H2O. When the commercial system is operated in an off-the-shelf manner, we find a clear cabin pressure–altitude dependency for N2O, CO2, and CO. The characteristics of this artifact make it difficult to reconcile with conventional calibration methods. We present a novel procedure that extends upon traditional calibration approaches in a high-flow system with high-frequency, short-duration sampling of a known calibration gas of near-ambient concentration. This approach corrects for cabin pressure dependency as well as other sources of drift in the analyzer while maintaining a ∼90 % duty cycle for 1 Hz sampling. Assessment and validation of the flight system with both extensive in-flight calibrations and comparisons with other flight-proven sensors demonstrate the validity of this method. In-flight 1σ precision is estimated at 0.05 ppb, 0.10 ppm, 1.00 ppb, and 10 ppm for N2O, CO2, CO, and H2O respectively, and traceability to World Meteorological Organization (WMO) standards (1σ) is 0.28 ppb, 0.33 ppm, and 1.92 ppb for N2O, CO2, and CO. We show the system is capable of precise, accurate 1 Hz airborne observations of N2O, CO2, CO, and H2O and highlight flight data, illustrating the value of this analyzer for studying N2O emissions on ∼100 km spatial scales.

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