Melting of ice by magma-ice-water interactions during subglacial eruptions as an indicator of heat transfer in subaqueous eruptions

2003 ◽  
pp. 61-72 ◽  
Author(s):  
Magnús T. Gudmundsson
Keyword(s):  
Heat Transfer ◽  
Subglacial Eruptions ◽  
Ice Water

scholarly journals Numerical simulation of formation and preservation of Ningwu ice cave, Shanxi, China

2015 ◽  
Vol 9 (2) ◽  
pp. 2367-2395 ◽  
Author(s):  
S. Yang ◽  
Y. Shi
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Process ◽  
Shanxi Province ◽  
Mechanism Of Formation ◽  
Annual Average ◽  
Average Temperature ◽  
Control Factors ◽  
Tourism Resource ◽  
Ice Water ◽  
Annual Average Temperature

Abstract. Ice caves exist in locations where annual average temperature in higher than 0 °C. An example is Ningwu ice cave, Shanxi Province, the largest ice cave in China. In order to quantitatively explain the mechanism of formation and preservation of the ice cave, we use Finite Element Method to simulate the heat transfer process at this ice cave. There are two major control factors. First, there is the seasonal asymmetric heat transfer. Heat is transferred into the ice cave from outside, very inefficiently by conduction in spring, summer and fall. In winter, thermal convection occurs that transfers heat very efficiently out of the ice cave, thus cooling it down. Secondly, ice–water phase change provides a heat barrier for heat transfer into the cave in summer. The calculation also helps to evaluate effects of global warming, tourists, etc. for sustainable development of ice cave as tourism resource. In some other ice caves in China, managers installed air-tight doors at these ice caves entrance intending to "protect" these caves, but this prevent cooling down these caves in winters and these cave ices will entirely melt within tens of years.

scholarly journals Exploration of Impinging Water Spray Heat Transfer at System Pressures Near the Triple Point

2013 ◽  
Author(s):  
Eric L. Golliher ◽  
Shi-chune Yao
Keyword(s):  
Heat Transfer ◽  
Triple Point ◽  
Low Pressure ◽  
Transfer Model ◽  
Space Vehicles ◽  
Water Spray ◽  
Flash Evaporation ◽  
Multiphase Transport ◽  
Triple Point Of Water ◽  
Ice Water

The heat transfer of a water spray impinging upon a surface in a very low pressure environment is of interest to cooling of space vehicles during launch and re-entry, and to industrial processes where flash evaporation occurs. At very low pressure, the process occurs near the triple point of water, and there exists a transient multiphase transport problem of ice, water and water vapor. At the impingement location, there are three heat transfer mechanisms: evaporation, freezing and sublimation. A preliminary heat transfer model was developed to explore the interaction of these mechanisms at the surface and within the spray.

Heat transfer with ice-water mixture flowing in a pipe

1969 ◽  
Vol 17 (2) ◽  
pp. 961-964
Author(s):  
S. I. Isataev ◽  
N. V. Masleeva
Keyword(s):  
Heat Transfer ◽  
Water Mixture ◽  
Ice Water

Circulation of heat to the hands of Arctic Indians

1960 ◽  
Vol 15 (4) ◽  
pp. 662-666 ◽  
Author(s):  
Robert W. Elsner ◽  
John D. Nelms ◽  
Laurence Irving
Keyword(s):  
Heat Transfer ◽  
Skin Temperature ◽  
Cold Water ◽  
White Men ◽  
Metabolic Heat ◽  
Cool Environment ◽  
Indian Men ◽  
Ice Water ◽  
Finger Skin ◽  
Skin Temperatures

Nine Indian men of an arctic village and eight urban white men have been compared in their responses to hand immersion in cold water. Following a 30-minute immersion in warm water (30°C) the hands were placed in cold water in an insulated bath (initially 5°C) for an additional 30 minutes. The rate of heat transfer to the water, finger skin temperatures and skin temperatures over a wrist vein were measured. All subjects were tested in this manner in two environmental situations: clothed in a warm room and unclothed in a cool room. In another experiment six Indians and five whites immersed their right hands in ice water while sitting confortably warm. Generally, the Indians showed a markedly superior ability to maintain hands warm in cold water. Their hands transferred more heat to the water whether the subjects were comfortably warm or chilly. In the cool environment hand heat loss was reduced in both groups, but the calculated heat transfer from circulation alone was still about twice as great in the Indians. The skin temperature measurements reflected the general trends of hand cooling and rewarming. The Indians withstood the hand immersion in ice water with quicker rewarming and less pain than the whites. Although their response is not conserving of metabolic heat, the loss is apparently trivial. The warming of the Indians' hands appears therefore to be adaptive in nature. Submitted on November 12, 1959

Wave formation and heat transfer at an ice-water interface in the presence of a turbulent flow

1980 ◽  
Vol 99 (3) ◽  
pp. 619-640 ◽  
Author(s):  
R. R. Gilpin ◽  
T. Hirata ◽  
K. C. Cheng
Keyword(s):  
Heat Transfer ◽  
Turbulent Flow ◽  
Heat Fluxes ◽  
Surface Pattern ◽  
Large Temperature ◽  
Water Interface ◽  
Mobile Bed ◽  
Ice Surface ◽  
Layer Flow ◽  
Ice Water

Under some conditions of temperature and flow an ice-water interface in the presence of a turbulent stream has been observed to be unstable. In this paper the source and the conditions for the instability were investigated for a well-defined turbulent boundary-layer flow. It was found that the instability resulted from the interaction that occurs between a wavy surface and a turbulent flow over it. Such an interaction results in a heat transfer variation which is 90 to 180 degrees out of phase with the surface wave shape – a result which is consistent with the calculations of Thorsness & Hanratty (1979a,b).The main factor controlling damping of the instability at an ice-water interface was found to be the rate at which heat is conducted away from the interface into the ice.In the past it has been found that when an ice layer is melting, that is when the heat conduction in the ice is small, the ice surface is highly unstable. In the present study it was found that for a sufficiently large temperature ratio (Tf−Tw)/(T∞−Tf), a steady-state ice layer is also unstable. Furthermore it is predicted, from the present observations, that a growing ice layer with a ratio of ice-side to water-side heat fluxes of up to 2.3 could be unstable.Under sufficiently unstable conditions waves on the ice surface grow to an amplitude at which flow separations occur near the wave crests. This results in a ‘rippled’ ice surface pattern very similar to the patterns observed on mobile bed surfaces (Kennedy 1969) or surfaces which are being dissolved into a flowing stream (Allen 1971). The development of a ‘rippled’ ice surface results in a very substantial increase in the mean heat-transfer rate which would have an important influence on predictions of ice formation in the presence of a turbulent stream.

scholarly journals Numerical simulation of formation and preservation of Ningwu ice cave, Shanxi, China

2015 ◽  
Vol 9 (5) ◽  
pp. 1983-1993 ◽  
Author(s):  
S. Yang ◽  
Y. Shi
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Process ◽  
Climatic Conditions ◽  
Shanxi Province ◽  
The Finite Element Method ◽  
Mechanism Of Formation ◽  
Control Factors ◽  
Tourism Resource ◽  
Colored Lights ◽  
Ice Water

Abstract. Ice caves exist in locations where annual average air temperature is higher than 0 °C. An example is Ningwu ice cave, Shanxi Province, the largest ice cave in China. In order to quantitatively investigate the mechanism of formation and preservation of the ice cave, we use the finite-element method to simulate the heat transfer process at this ice cave. There are two major control factors. First, there is the seasonal asymmetric heat transfer. Heat is transferred into the ice cave from outside very inefficiently by conduction in spring, summer and fall. In winter, thermal convection occurs that transfers heat very efficiently out of the ice cave, thus cooling it down. Secondly, ice–water phase change provides a heat barrier for heat transfer into the cave in summer. The calculation also helps to evaluate effects of global warming, tourists, colored lights, climatic conditions, etc. for sustainable development of the ice cave as a tourism resource. In some other ice caves in China, managers have installed airtight doors at these ice caves' entrances with the intention of "protecting" these caves, but this in fact prevents cooling in winter and these cave ices will entirely melt within tens of years.

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