Steady-State Longitudinal and Radial Temperature Distributions in Internally Heated Finite Wires

1958 ◽  
Vol 50 (5) ◽  
pp. 837-848 ◽  
Author(s):  
Georg W. Preckshot ◽  
John W. Gorman
Keyword(s):  
Steady State ◽  
Radial Temperature ◽  
Temperature Distributions

scholarly journals Numerical Investigation of Air Conditioners’ Control Unit Position On Temperature Distribution and Energy Consumptions of a Room

2019 ◽  
Vol 111 ◽  
pp. 02039
Author(s):  
Mustafa Mutlu ◽  
Emre Çalışkan
Keyword(s):  
Steady State ◽  
Temperature Distribution ◽  
Control Unit ◽  
Air Conditioners ◽  
Comfort Levels ◽  
Temperature Distributions ◽  
Energy Consumptions ◽  
Cooling Loads ◽  
Homogeneous Temperature ◽  
Comfort Criteria

Minimum temperature difference should be achieved in conditioned rooms to meet comfort criteria. It is desired that the temperature set by a user from the control unit, should be the same in the entire room. Therefore, the position of the control unit plays a significant role in order to achieve a homogeneous temperature distribution in the room. In this study, the effect of control unit positioning on temperature and velocity distributions in a room, where a cassette type indoor unit was applied, was numerically investigated. Blowing temperature and speed of the indoor unit has been adjusted by the temperature value that measured by a control unit which was placed at five different locations, in order to examine positioning effects of the control unit. Predicted percentage dissatisfied (PPD) values were calculated, and uncomfortable zones were determined by 2-dimensional analyses. Cooling loads, as well as energy consumptions, were calculated and their variations according to the position of control unit was figured out in steady state conditions. The results showed that control unit positioning not only influences the comfort levels or temperature distributions in a room but also energy consumptions.

The Analysis of Influence of Fuel Pellet and Coolant Temperature Distributions on the VVER-1000 Active Core Characteristics

2013 ◽  
Author(s):  
A. A. Mishin ◽  
V. V. Galchenko
Keyword(s):  
Fuel Assembly ◽  
Cross Sections ◽  
Fuel Pellet ◽  
Coolant Temperature ◽  
Radial Temperature ◽  
Group Constant ◽  
Temperature Distributions ◽  
Active Core ◽  
Core Characteristics

The accuracy and quality of neutron-physical calculations of the active core characteristics depend heavily on the few-group constant preparation procedure. The method, based on using average in the fuel assembly fuel and coolant parameters is currently used for preparing macroscopic cross-sections. The question is what impact would considering the uneven distribution of those parameters, made on the few-group constant preparation stage exert on further analysis of the reactor facility behavior during steady-state and transients operation. The study carries out comparative analysis of the neutron-physical characteristics of the VVER-1000 core using the standard approach and using distributed in the fuel assembly fuel and coolant parameters while preparing few-group constants. It’s revealed that the fuel pellet and coolant radial temperature distributions affect the multiplication factor and temperature reactivity effect values.

scholarly journals Calculations of Velocity and Temperature in a Polar Glacier using the Finite-Element Method

1979 ◽  
Vol 24 (90) ◽  
pp. 131-146 ◽  
Author(s):  
Roger LeB. Hooke ◽  
Charles F. Raymond ◽  
Richard L. Hotchkiss ◽  
Robert J. Gustafson
Keyword(s):  
Finite Element ◽  
Steady State ◽  
Temperature Distribution ◽  
Differential Equations ◽  
Boundary Conditions ◽  
Velocity Distribution ◽  
Vertical Velocity ◽  
Measured Temperature ◽  
Temperature Distributions ◽  
Flow Law

AbstractNumerical methods based on quadrilateral finite elements have been developed for calculating distributions of velocity and temperature in polar ice sheets in which horizontal gradients transverse to the flow direction are negligible. The calculation of the velocity field is based on a variational principle equivalent to the differential equations governing incompressible creeping flow. Glen’s flow law relating effective strain-rateε̇ and shear stressτbyε̇ = (τ/B)nis assumed, with the flow law parameterBvarying from element to element depending on temperature and structure. As boundary conditions, stress may be specified on part of the boundary, in practice usually the upper free surface, and velocity on the rest. For calculation of the steady-state temperature distribution we use Galerkin’s method to develop an integral condition from the differential equations. The calculation includes all contributions from vertical and horizontal conduction and advection and from internal heat generation. Imposed boundary conditions are the temperature distribution on the upper surface and the heat flux elsewhereFor certain simple geometries, the flow calculation has been tested against the analytical solution of Nye (1957), and the temperature calculation against analytical solutions of Robin (1955) and Budd (1969), with excellent results.The programs have been used to calculate velocity and temperature distributions in parts of the Barnes Ice Cap where extensive surface and bore-hole surveys provide information on actual values. The predicted velocities are in good agreement with measured velocities if the flow-law parameterBis assumed to decrease down-glacier from the divide to a point about 2 km above the equilibrium line, and then remain constant nearly to the margin. These variations are consistent with observed and inferred changes in fabric from fine ice with randomc-axis orientations to coarser ice with single- or multiple-maximum fabrics. In the wedge of fine-grained deformed superimposed ice at the margin,Bincreases again.Calculated and measured temperature distributions do not agree well if measured velocities and surface temperatures are used in the model. The measured temperature profiles apparently reflect a recent climatic warming which is not incorporated into the finite-element model. These profiles also appear to be adjusted to a vertical velocity distribution which is more consistent with that required for a steady-state profile than the present vertical velocity distribution.

The photoelastic determination of thermal stress concentrations in grooved cylinders with a radial temperature gradient

1979 ◽  
Vol 14 (3) ◽  
pp. 95-102 ◽  
Author(s):  
F A Khayyat ◽  
P Stanley
Keyword(s):  
Thermal Stress ◽  
Steady State ◽  
Temperature Gradient ◽  
Scattered Light ◽  
Radial Temperature Gradient ◽  
Stress Concentrations ◽  
Radial Temperature ◽  
Hollow Cylinders ◽  
Non Destructive

A non-destructive photoelastic technique, requiring integrated retardation and scattered-light measurements, is used for the determination of thermal stress concentrations in hollow cylinders with (i) an internal and (ii) an external curcumferential groove, subjected to a steady-state radial temperature gradient.

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