Listvenite formation during mass transfer into the leading edge of the mantle wedge: Initial results from Oman Drilling Project Hole BT1B

2022 ◽  
Author(s):  
Peter B. Kelemen ◽  
Juan Carlos de Obeso ◽  
James A. Leong ◽  
Marguerite Godard ◽  
Keishi Okazaki ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Mantle Wedge ◽  
Leading Edge ◽  
Initial Results ◽  
Drilling Project

Mass transfer into the leading edge of the mantle wedge: Initial results from Oman Drilling Project Hole BT1B

2021 ◽  
Author(s):  
Peter B Kelemen ◽  
Juan Carlos de Obeso ◽  
James Andrew Leong ◽  
Marguerite Godard ◽  
Keishi Okazaki ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Mantle Wedge ◽  
Leading Edge ◽  
Initial Results ◽  
Drilling Project

scholarly journals Highly Resolved Distribution of Heat Transfer for Turbine Leading Edge Film Cooling Including Reynolds Number and Blowing Rate Effects

1998 ◽  
Author(s):  
K. Jung ◽  
D. K. Hennecke
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Reynolds Number ◽  
Film Cooling ◽  
Heat Mass Transfer ◽  
Leading Edge ◽  
Transfer Coefficients ◽  
Complex Flow ◽  
Long Distance ◽  
Naphthalene Sublimation Technique

The effect of leading edge film cooling on heat transfer was experimentally investigated using the naphthalene sublimation technique. The experiments were performed on a symmetrical model of the leading edge suction side region of a high pressure turbine blade with one row of film cooling holes on each side. Two different lateral inclinations of the injection holes were studied: 0° and 45°. In order to build a data base for the validation and improvement of numerical computations, highly resolved distributions of the heat/mass transfer coefficients were measured. Reynolds numbers (based on hole diameter) were varied from 4000 to 8000 and blowing rate from 0.0 to 1.5. For better interpretation, the results were compared with injection-flow visualizations. Increasing the blowing rate causes more interaction between the jets and the mainstream, which creates higher jet turbulence at the exit of the holes resulting in a higher relative heat transfer. This increase remains constant over quite a long distance dependent on the Reynolds number. Increasing the Reynolds number keeps the jets closer to the wall resulting in higher relative heat transfer. The highly resolved heat/mass transfer distribution shows the influence of the complex flow field in the near hole region on the heat transfer values along the surface.

Modeling of convective heat-mass transfer in permeable parts of seismic focal zones of the Kamchatka region and associated volcanic arcs

2021 ◽  
Author(s):  
Yuri Perepechko ◽  
Konstantin Sorokin ◽  
Anna Mikheeva ◽  
Viktor Sharapov ◽  
Sherzad Imomnazarov
Keyword(s):  
Mass Transfer ◽  
Mantle Wedge ◽  
Earth’S Crust ◽  
Magma Chambers ◽  
Volcanic Arcs ◽  
Fluid Systems ◽  
The Pacific ◽  
Kamchatka Region ◽  
The Pacific Ocean ◽  
Earth's Crust

<p>The paper presents a non-isothermal model of hydrodynamic heating of lithospheric rocks above magma chambers in application to the seismic focal zone of the Kamchatka region and associated volcanic arcs. The effect of convective heating of mantle and crustal rocks on dynamics of metasomatic changes and convective melting was studied. In the existing models of ore-forming systems, fluid mass transfer is determined mainly by the retrograde boiling of magmas in meso-abyssal intrusive chambers. Analysis of the manifestations of deposits of the porphyry formation of the Pacific Ocean active margins shows the decisive participation in their formation of mantle-crust ore-igneous systems. The model of convective heat-mass transfer in fluid mantle-crust systems coupled with magma chambers is designed with the consideration of effects of interphase interaction in rocks of permeable zones above igneous fluid sources. Numerical simulation of the dynamics of fluid systems under the volcanoes of the frontal zone of Kamchatka shows altered ultramafic rocks in metasomatic zoning and the presence of facial changes in the mineral composition of wehrlitized rocks. In the mantle wedge of the northwestern margin of the Pacific Ocean, over which epicontinental volcanic arcs developed in the post-Miocene stage, there is possible combination of the products of different-time and different-level igneous systems in the same permeable "earth's crust-lithospheric mantle" transition zones. Assuming that the "cratonization" of volcanic sections of the continental Earth's crust follows the "metasomatic granitization" pattern, the initial element of which is the wehrlitization of mantle wedge ultramafic rocks, the processes of metasomatic fertilization of mantle wedge rocks were investigated using a flow-through multiple-reservoir reactor. In the seismically active regions of the Pacific transition lithosphere, specific conditions for heating of areas of increased permeability above mantle fluid sources should be recorded. Metasomatic columns in such fluid systems can describe the formation of at least three levels of convective melting of metasomatized mantle wedge substrates, as well as the formation of a region of high-temperature fluid change of mafic intrusion rocks in the Earth's crust. The work was financially supported by the Russian Foundation for Basic Research, grants No. 19-05-00788.</p>

Magmatic record of continuous Neo-Tethyan subduction after initial India-Asia collision in the central part of southern Tibet

2020 ◽  
Author(s):  
Feng Huang ◽  
Tyrone O. Rooney ◽  
Ji-Feng Xu ◽  
Yun-Chuan Zeng
Keyword(s):  
Mantle Wedge ◽  
Leading Edge ◽  
Continental Collision ◽  
Southern Tibet ◽  
Mafic Rocks ◽  
Lhasa Terrane ◽  
Slab Breakoff ◽  
Geodynamic Processes ◽  
Generation Mechanisms ◽  
Transitional Phase

The Lhasa Terrane in southern Tibet is the leading edge of the Tibet-Himalaya Orogen and represents a fragmentary record of terminal oceanic subduction. Thus, it is an ideal region for studying magmatism and geodynamic processes that occurred during the transition from oceanic subduction to continental collision and/or oceanic slab breakoff. Here we examine a suite of early Cenozoic mafic rocks (ca. 57 Ma) within the central part of Lhasa Terrane, southern Tibet, which erupted during a transitional phase between the onset of India-Asia continental collision and Neo-Tethyan slab breakoff. These rocks display a geochemical affinity with magmas produced by fluid-fluxed melting of the mantle wedge within a subduction zone environment. The whole-rock element and Sr-Nd isotope compositions of these mafic rocks are similar to those of Cretaceous subduction-related magmatism in southern Tibet, demonstrating the sustained influence of the Neo-Tethys Ocean slab on the mantle wedge during the onset of the collision of India and Asia. The results of our geochemical forward modeling constrain the conditions of melt generation at depths of 1.3−1.5 GPa with significant fluid additions from the Neo-Tethyan slab. These results provide the first petrological and geochemical evidence that slab flux-related magmatism continued despite the commencement of continental collision. While existing studies have suggested that magmas were derived from melting of the Neo-Tethyan slab during this period, our new results suggest that additional magma generation mechanisms were active during this transitional phase.

The Effect of Mass Transfer on Free Convection

1960 ◽  
Vol 82 (3) ◽  
pp. 260-263 ◽  
Author(s):  
R. Eichhorn
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Free Convection ◽  
Skin Friction ◽  
Leading Edge ◽  
Temperature Profiles ◽  
Constant Wall Temperature ◽  
Constant Property ◽  
Boundary Layer Equations ◽  
Similar Solutions

Consideration is given to the constant property laminar boundary layer equations with free convection and mass transfer. It is shown that similar solutions are possible for blowing rate distributions varying as the distance from the leading edge raised to the power (n − 1)/4 where n is the exponent in a power law surface temperature distribution. Solutions to the equations in the form of skin friction and heat-transfer parameters, and velocity and temperature profiles are presented for the constant wall temperature case for a fluid with Pr = 0.73. The cases considered range from strong suction to strong blowing. Mass transfer has a pronounced effect on the heat transfer but only a slight effect on the skin friction. In light of the solutions presented, these effects are shown to be physically rational.

Film Cooling Effect of Rotor-Stator Purge Flow on Endwall Heat/Mass Transfer

2011 ◽  
Vol 134 (4) ◽  
Author(s):  
M. Papa ◽  
V. Srinivasan ◽  
R. J. Goldstein
Keyword(s):  
Mass Transfer ◽  
Leading Edge ◽  
Recirculation Region ◽  
Pressure Side ◽  
Blade Profile ◽  
Suction Surface ◽  
Cooling Effectiveness ◽  
Blowing Ratio ◽  
Passage Vortex ◽  
Purge Flow

Mass transfer measurements on the endwall and blade suction surfaces are performed in a five-blade linear cascade with a high-performance rotor blade profile. The effects of purge flow from the wheelspace cavity entering the hot gas path are simulated by injecting naphthalene-free and naphthalene-saturated air through a slot upstream of the blade row at 45 deg to the endwall, for a Reynolds number of 6×105 based on blade true chord and cascade exit velocity, and blowing ratios of 0.5, 1, and 1.5. Oil-dot visualization indicates that with injection, a recirculation region is set up upstream of the leading edge, and the growth of the passage vortex is altered. The coolant exiting from the slot is drawn to the suction side of the blade and is pushed up along the suction surface of the blade by the secondary flow. For blowing ratios of 0.5 and 1.0, only a little coolant reaches the pressure side in the aft part of the passage. However, at a blowing ratio of 1.5, there is a dramatic change in the flow structure. Both the oil-dot visualization and the cooling effectiveness maps indicate that at this blowing ratio, the coolant exiting the slot has sufficient momentum to closely follow the blade profile and is not significantly entrained into the passage vortex. As a result, high cooling effectiveness values are obtained at the pressure side of the endwall, well into the midchord and aft portions of the blade passage.

Film Cooling Effect of Rotor-Stator Purge Flow on Endwall Heat/Mass Transfer

2010 ◽  
Author(s):  
M. Papa ◽  
V. Srinivasan ◽  
R. J. Goldstein
Keyword(s):  
Mass Transfer ◽  
Leading Edge ◽  
Recirculation Region ◽  
Pressure Side ◽  
Blade Profile ◽  
Suction Surface ◽  
Cooling Effectiveness ◽  
Blowing Ratio ◽  
Passage Vortex ◽  
Purge Flow

Mass transfer measurements on the endwall and blade suction surfaces are performed in a five-blade linear cascade with a high-performance rotor blade profile. The effects of purge flow from the wheelspace cavity entering the hot gas path are simulated by injecting air through a slot upstream of the blade row at 45° to the endwall, for Reynolds number of 6×105 based on blade true chord and cascade exit velocity, and blowing ratios of 0.5, 1 and 1.5. Detailed maps of cooling effectiveness on the passage endwall and blade suction surface are generated for the cases of injection of naphthalene-free and naphthalene-saturated air. Oil-dot visualization indicates that with injection, a recirculation region is set up upstream of the leading edge, and the growth of the passage vortex is altered. The coolant exiting from the slot is drawn to the suction side of the blade and is pushed up along the suction surface of the blade by the secondary flow. For blowing ratios of 0.5 and 1.0, only a little coolant reaches the pressure side in the aft part of the passage. However, at a blowing ratio of 1.5, there is a dramatic change in the flow structure. Both the oil dot visualization and the cooling effectiveness maps indicate that at this blowing ratio, the coolant exiting the slot has sufficient momentum to closely follow the blade profile, and is not significantly entrained into the passage vortex. As a result, high cooling effectiveness values are obtained at the pressure side of the endwall, well into the mid-chord and aft portions of the blade passage.

scholarly journals An Investigation of Heat Transfer by Leading Edge Film Cooling Applying the Naphthalene Sublimation Technique

1996 ◽  
Author(s):  
J. Richter ◽  
K. Jung ◽  
D. K. Hennecke
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Film Cooling ◽  
Incidence Angle ◽  
Leading Edge ◽  
Naphthalene Sublimation Technique ◽  
Naphthalene Sublimation ◽  
Sublimation Technique

The dependence of heat transfer on film cooling near the leading edge of a blade was investigated using the naphthalene sublimation technique and applying the analogy between heat and mass transfer. Therefore, the local sublimation rate with and without film cooling was measured. The symmetric leading edge was cooled by an air mass flow out of two staggered rows of holes. The measurements were carried out with a constant Reynolds number Re = 80000, different incidence angles φ = 0° to 10° and a blowing rate varying from M = 0.3 to 2.5. The flow without film cooling was visualized around the leading edge with smoke to indicate the existence of separation bubbles. To determine the dependence of incidence angle and blowing rate on jet trajectories, smoke was mixed to the cooling air. The mass transfer coefficient was determined with the naphthalene sublimation technique. Due to the high resolution of the sublimation technique the local mass transfer distribution around the cooling holes could also be measured. Furthermore, the location of stagnation points and separation bubbles were investigated. The results of the tests without film cooling were also compared with those obtained by observing stagnation point mass transfer on a cylinder and with those by laminar flow across a flat plate. The mass transfer coefficient of film cooling experiments was related to the mass transfer coefficient without film cooling to describe the local dependence of heat transfer coefficient on film cooling. An increase on relativ heat transfer near the film cooling holes is obtained by increasing the blowing rate. No further influence on heat transfer along the pressure side is detected for an incidence angle larger than 10° as the cooling films were shifted around the leading edge from the pressure to the suction side.

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