Crustal structure of the Valhalla complex, British Columbia, from Lithoprobe seismic-reflection and potential-field data

1990 ◽  
Vol 27 (8) ◽  
pp. 1048-1060 ◽  
Author(s):  
David W. S. Eaton ◽  
Frederick A. Cook
Keyword(s):  
Heat Flux ◽  
North American ◽  
Seismic Reflection ◽  
Surface Heat Flux ◽  
Field Data ◽  
High Surface ◽  
Surface Heat ◽  
Upper Crust ◽  
Potential Field Data ◽  
Lower Crustal

The Valhalla complex, situated in the Omineca crystalline belt in southeastern British Columbia, is a Cordilleran metamorphic core complex bordering the suture zone between Quesnellia and North American rocks. The region is tectonically interposed between a convergent plate margin along Canada's west coast and the stable North American craton, and is characterized by a crustal thickness of ~ 35 km, high surface heat flux, and elevated lower crustal electrical conductivity. In this study, Lithoprobe deep-crustal seismic-reflection data, potential-field data, and geological constraints have been used to gain a better understanding of crustal structure in the vicinity of the Valhalla complex. Analysis of Bouguer gravity and total-field aeromagnetic data indicates that mafic oceanic rocks and various syn- and post-accretionary granitoid plutonic rocks are not major constituents of the upper crust underlying the complex. The seismic data reveal a moderately reflective upper crust and image several fault zones, including a very high amplitude, west-dipping reflection that is interpreted as a significant Late Cretaceous or Paleocene thrust fault. The fault-zone reflectivity may be related to compositional heterogeneity and (or) seismic anisotropy associated with mylonites. The lower crust appears to be nonreflective, in contrast with other areas of high surface heat flux and elevated lower crustal conductivity. Taken together, the various data show that the Valhalla complex is likely cored by North American metasedimentary rocks and reveal features related to the Jurassic to Paleocene compressional fabric, which has been largely overprinted at the surface by subsequent Eocene extension.

scholarly journals The impact of wintertime sea-ice anomalies on high surface heat flux events in the Iceland and Greenland Seas

2020 ◽  
Vol 54 (3-4) ◽  
pp. 1937-1952
Author(s):  
James O. Pope ◽  
Thomas J. Bracegirdle ◽  
Ian A. Renfrew ◽  
Andrew D. Elvidge
Keyword(s):  
Heat Flux ◽  
Sea Ice ◽  
Surface Heat Flux ◽  
High Surface ◽  
Surface Heat ◽  
The Impact

Onset of drying of a porous particle bed immersed in saturated water and heated with a high surface heat flux

2020 ◽  
Vol 176 ◽  
pp. 115358
Author(s):  
Kunito Okuyama ◽  
Satomi Kawanishi ◽  
Risa Aoki
Keyword(s):  
Heat Flux ◽  
Surface Heat Flux ◽  
High Surface ◽  
Surface Heat ◽  
Porous Particle ◽  
Saturated Water ◽  
Particle Bed

scholarly journals Capturing Day-to-day Diurnal Variations in Stability in the Convective Atmospheric Boundary Layer Using Large Eddy Simulation

2018 ◽  
Vol 12 (1) ◽  
pp. 107-131 ◽  
Author(s):  
Jordan Nielson ◽  
Kiran Bhaganagar
Keyword(s):  
Heat Flux ◽  
Standard Deviation ◽  
Surface Heat Flux ◽  
Field Data ◽  
Geostrophic Wind ◽  
Surface Heat ◽  
Diurnal Cycles ◽  
Eddy Simulation ◽  
Large Eddy ◽  
The Mean

Introduction:Large Eddy Simulation (LES) modelers must begin to answer the question of how to better incorporate large datasets into simulations. This question is important because, at a given location, the diurnal, seasonal, and day-to-day variations of atmospheric stability have significant consequences for the power generated by wind turbines. The following study provides a methodology to obtain discrete values of surface flux, inversion height and geostrophic wind for LES using field data over multiple diurnal cycles (averaged over a month) at 12 Local Time (LT) (during the convective ABL). The methodology will allow the discrete LES to quantify the day-to-day variations over multiple diurnal cycles.Methods:The study tests the hypothesis that LES can capture the mean velocity and TKE profiles from the averaged variations in surface heat flux at 12 LT measured in the field (mean, +1 standard deviation, and -1 standard deviation). The discrete LES from the mean, +1 standard deviation, and -1 standard deviation surface heat flux represent the variations in the ABL due to the day-to-day variations in surface heat flux. The method calculates the surface heat flux for the NREL NWTC M5 dataset. The field data were used to generate Probability Density Functions (PDFs) of surface heat flux for the January and July 12 LT. The PDFs are used to select the surface heat fluxes as inputs into the discrete LES.Results / Conclusion:A correlation function between the surface heat flux and the boundary layer height was determined to select the initial inversion height, and the geostrophic departure function was used to determine the geostrophic wind for each surface heat flux. The LES profiles matched the averaged velocity profiles from the field data to 4% and the averaged TKE profiles to 6% and, therefore, validated the methodology. The method allows for further quantification of day-to-day stability variations using LES.

Analysis of significant measures for thermal conductivity

2020 ◽  
pp. 35-42
Author(s):  
Yuri P. Zarichnyak ◽  
Vyacheslav P. Khodunkov
Keyword(s):  
Thermal Conductivity ◽  
Heat Flux ◽  
Surface Heat Flux ◽  
Heat Flux Density ◽  
Measurement Method ◽  
Conductivity Measurement ◽  
Surface Heat ◽  
Measuring Instrument ◽  
New Class ◽  
Achievable Accuracy

The analysis of a new class of measuring instrument for heat quantities based on the use of multi-valued measures of heat conductivity of solids. For example, measuring thermal conductivity of solids shown the fallacy of the proposed approach and the illegality of the use of the principle of ambiguity to intensive thermal quantities. As a proof of the error of the approach, the relations for the thermal conductivities of the component elements of a heat pump that implements a multi-valued measure of thermal conductivity are given, and the limiting cases are considered. In two ways, it is established that the thermal conductivity of the specified measure does not depend on the value of the supplied heat flow. It is shown that the declared accuracy of the thermal conductivity measurement method does not correspond to the actual achievable accuracy values and the standard for the unit of surface heat flux density GET 172-2016. The estimation of the currently achievable accuracy of measuring the thermal conductivity of solids is given. The directions of further research and possible solutions to the problem are given.

COMBINED CONVECTION BOUNDARY-LAYER FLOW ALONG A VERTICAL CYLINDER WITH A POROUS WALL AND SURFACE HEAT FLUX

2012 ◽  
Vol 43 (6) ◽  
pp. 483-507
Author(s):  
Abbasali Abouei Mehrizi ◽  
Ganji Domairry ◽  
V. Khamseh
Keyword(s):  
Boundary Layer ◽  
Heat Flux ◽  
Boundary Layer Flow ◽  
Surface Heat Flux ◽  
Vertical Cylinder ◽  
Porous Wall ◽  
Surface Heat ◽  
Convection Boundary Layer ◽  
Convection Boundary ◽  
Layer Flow

Heat Transfer Characteristics of Downward Facing Hot Horizontal Surfaces Using Mist Jet Impingement

2017 ◽  
Author(s):  
Ashutosh Kumar Yadav ◽  
Parantak Sharma ◽  
Avadhesh Kumar Sharma ◽  
Mayank Modak ◽  
Vishal Nirgude ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Surface Heat Flux ◽  
Cooling System ◽  
Water Pressure ◽  
Jet Impingement ◽  
Surface Heat ◽  
Heat Transfer Characteristics ◽  
Impingement Cooling ◽  
Transfer Characteristics

Impinging jet cooling technique has been widely used extensively in various industrial processes, namely, cooling and drying of films and papers, processing of metals and glasses, cooling of gas turbine blades and most recently cooling of various components of electronic devices. Due to high heat removal rate the jet impingement cooling of the hot surfaces is being used in nuclear industries. During the loss of coolant accidents (LOCA) in nuclear power plant, an emergency core cooling system (ECCS) cool the cluster of clad tubes using consisting of fuel rods. Controlled cooling, as an important procedure of thermal-mechanical control processing technology, is helpful to improve the microstructure and mechanical properties of steel. In industries for heat transfer efficiency and homogeneous cooling performance which usually requires a jet impingement with improved heat transfer capacity and controllability. It provides better cooling in comparison to air. Rapid quenching by water jet, sometimes, may lead to formation of cracks and poor ductility to the quenched surface. Spray and mist jet impingement offers an alternative method to uncontrolled rapid cooling, particularly in steel and electronics industries. Mist jet impingement cooling of downward facing hot surface has not been extensively studied in the literature. The present experimental study analyzes the heat transfer characteristics a 0.15mm thick hot horizontal stainless steel (SS-304) foil using Internal mixing full cone (spray angle 20 deg) mist nozzle from the bottom side. Experiments have been performed for the varied range of water pressure (0.7–4.0 bar) and air pressure (0.4–5.8 bar). The effect of water and air inlet pressures, on the surface heat flux has been examined in this study. The maximum surface heat flux is achieved at stagnation point and is not affected by the change in nozzle to plate distance, Air and Water flow rates.

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