The Optimum Decision on Heat Production and Heat Transfer for Minimizing Heat Production Cost in Heat Network

2019 ◽  
Vol 45 (2) ◽  
pp. 125-137
Author(s):  
Heung Seob Kim ◽  
Won Young Yun
Keyword(s):  
Heat Transfer ◽  
Heat Production ◽  
Production Cost ◽  
Heat Network ◽  
Optimum Decision

Fetal and uteroplacental heat production in sheep

1986 ◽  
Vol 61 (6) ◽  
pp. 2018-2022 ◽  
Author(s):  
R. D. Gilbert ◽  
G. G. Power
Keyword(s):  
Heat Transfer ◽  
Heat Production ◽  
Fetal Death ◽  
Internal Iliac Artery ◽  
Uterine Blood Flow ◽  
Fick Principle ◽  
Uterine Muscle ◽  
Internal Iliac ◽  
The Common ◽  
Per Se

To separate heat production of the fetus from that of the placenta, endometrium, and uterine muscle, we measured total uterine heat production first with the fetus intact and then after the umbilical cord was snared and the fetus killed. Heat production was measured with the Fick principle using thermistors chronically implanted in a maternal artery and major uterine vein and a flowmeter placed on the common internal iliac artery. In nine ewes, carrying lambs weighing 4.46 +/- 0.42 (SE) kg, total uterine heat production fell from 10.6 to 2.9 W after fetal death. Uterine blood flow fell progressively to 90% of control levels during the first hour after death. The caloric equivalent for O2 averaged 4.1 cal/ml O2 for the uterus, 2.2 for the uteroplacenta, and 4.6 for the fetus per se. It was not possible to explain these results using a simple model of maternal-fetal heat transfer. Rather, it was necessary to assume an additional pathway for heat transfer between small uterine veins on the surface of the uterus and cooler structures in the maternal abdomen, presumably the ventral abdominal wall.

The Role of the Skin in Heat Transfer

1960 ◽  
Vol 82 (3) ◽  
pp. 239-241 ◽  
Author(s):  
A. M. Stoll
Keyword(s):  
Heat Transfer ◽  
Heat Exchange ◽  
Energy Balance ◽  
Functional Capacity ◽  
Heat Production ◽  
Thermal Exchange ◽  
Orderly Fashion ◽  
Fundamental Research ◽  
The Impact

The author considers lines of fundamental research and the impact of human factors in the area of thermal exchange. Logically, this area of investigation may be divided into: (a) Heat exchange between man and his environment; and (b) internal energy balance between heat production and heat loss. Very little information has been compiled in an orderly fashion concerning the skin through which heat must flow in both directions to maintain man in his environment in a functional capacity. It is therefore the purpose of this paper to consider the human skin, its dimensions and properties with respect to its role in heat transfer, and the effects of its impairment or injury.

scholarly journals Experimental and simulation study of heat transfer in fluidized beds with heat production

2017 ◽  
Vol 317 ◽  
pp. 242-257 ◽  
Author(s):  
Z. Li ◽  
T.C.E. Janssen ◽  
K.A. Buist ◽  
N.G. Deen ◽  
M. van Sint Annaland ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Simulation Study ◽  
Heat Production ◽  
Fluidized Beds

Environmental modifications in a pig growth model for early-weaned piglets

1989 ◽  
Vol 48 (3) ◽  
pp. 591-599
Author(s):  
L. D. Jacobson ◽  
S. G. Cornelius ◽  
K. A. Jordan
Keyword(s):  
Heat Transfer ◽  
Thermal Resistance ◽  
Growth Model ◽  
Heat Production ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Daily Growth ◽  
Environmental Component ◽  
Piglet Growth ◽  
Latent Heat Loss

ABSTRACTA food-driven pig growth model was developed from two existing mathematical models. The new model predicts daily growth and heat production of early-weaned pigs. An existing pig growth model was altered by replacing the environmental component with a heat transfer model. The heat transfer model was further refined by partitioning latent heat loss between the skin and lungs, adding a thermal resistance for hair coat, and increasing tissue thermal resistance. Results from this combined model were compared with experimental observations of daily piglet growth and heat production at 15°C, 20°C, 25°C and 30°C. Good agreement existed between observed data and model predictions for piglet growth. Heat production predictions did not compare as well with experimental observations as did growth, especially when piglets lost weight.

scholarly journals Heat loss from deer mice (Peromyscus): evaluation of seasonal limits to thermoregulation

1986 ◽  
Vol 126 (1) ◽  
pp. 249-269 ◽  
Author(s):  
K. E. Conley ◽  
W. P. Porter
Keyword(s):  
Heat Transfer ◽  
Heat Loss ◽  
Heat Production ◽  
Mechanistic Model ◽  
Production Capacity ◽  
Deer Mice ◽  
Clear Night ◽  
Winter Conditions ◽  
Seasonal Adaptations ◽  
Air Temperatures

This paper investigates the influence of seasonal adaptations to thermoregulatory heat loss for deer mice (Peromyscus) during summer and winter. A general, mechanistic model of heat transfer through fur was evaluated for the structural properties of the fur of deer mice. The model was validated against heat production determined from mice exposed to a range of radiative (wall) temperatures (tr) at air temperatures (ta) of 15, 27 and 34 degrees C. Calculated heat loss from the appendages was subtracted from the measured heat production to yield heat loss from the furred torso. This calculated torso heat loss agreed closely with the predicted fur heat loss for all conditions, as shown by a regression slope near 1 (0.99). Simulations using models of fur and appendage heat loss reveal that the winter increase in thermogenic (heat production) capacity has a greater effect than changes in fur properties in expanding the limits to thermoregulation. Both wind and a clear night sky increase heat loss and can limit thermoregulation to air temperatures above those found in deer mice habitats during winter (−25 degrees C). Thus, despite seasonal adaptations, these simulations indicate that thermoregulation is not possible under certain winter conditions, thereby restricting deer mice to within the protected environment of the leaf litter or snow tunnels.

Precise Control of Frozen Region During Cryosurgery Utilizing Peltier Effect

2007 ◽  
Author(s):  
Hiroki Takeda ◽  
Shigenao Maruyama ◽  
Setsuya Aiba ◽  
Atsuki Komiya
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Heating Rate ◽  
Heat Production ◽  
Animal Experiment ◽  
Peltier Effect ◽  
Cooling Performance ◽  
Precise Control ◽  
Diseased Part ◽  
Peltier Module

In cryosurgery, it is necessary to control heat transfer precisely and actively in order to necrotize diseased part effectively and to avoid freezing healthy tissues. In order to control heat transfer, the cryoprobe utilizing peltier module was developed. This cryoprobe makes it possible to control cooling and heating rate actively and precisely due to peltier effect. Therefore, it is convenient to control the size of cell-destroyed area. In order to confirm cooling performance of the cryoprobe, gelatin cooling experiment and animal experiment was conducted. From the results, it can be said that this cryoprobe has enough cooling performance to destroy undesirable cell and it can control cooling and heating rate actively. Numerical simulation which considers biological heat production, freezing of tissue and peltier effect at same time was developed in order to evaluate frozen region or necrotized area, which are difficult to be measured.

Laminar Heat Transfer in a Channel With Unsteady Flow and Wall Heating Varying With Position and Time

1963 ◽  
Vol 85 (4) ◽  
pp. 358-365 ◽  
Author(s):  
R. Siegel ◽  
M. Perlmutter
Keyword(s):  
Heat Transfer ◽  
Cross Section ◽  
Heat Production ◽  
Fluid Velocity ◽  
Isothermal Condition ◽  
Convection Heat Transfer ◽  
Channel Cross Section ◽  
Fluid Temperature ◽  
Parallel Plates ◽  
General Relations

An analysis is made of incompressible laminar forced convection heat transfer between two parallel plates that have a specified heat production to be dissipated at their surfaces. The heat production can vary in an arbitrary manner with time and position along the channel, starting from an initially isothermal condition. The fluid velocity is assumed constant over the channel cross section, but can vary with time. The variation of fluid temperature over the channel cross section is accounted for. General relations are presented in closed form and their application is illustrated by carrying out some typical examples. The results are compared with previous analyses that have assumed constant temperatures over the channel cross section and a constant heat-transfer coefficient.

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