IMPACT OF EXTERNAL TEMPERATURE DISTRIBUTION ON THE TURBULENT AND THERMAL FIELDS IN A VERTICAL UNIFORMLY HEATED CHANNEL

2018 ◽  
Author(s):  
Martin Thebault ◽  
Stephanie Giroux-Julien ◽  
Victoria Timchenko ◽  
Christophe Menezo ◽  
John Reizes
Keyword(s):  
Temperature Distribution ◽  
External Temperature ◽  
Thermal Fields ◽  
Heated Channel

scholarly journals Thermal distribution analysis of inner defects in TSV

2018 ◽  
Vol 38 ◽  
pp. 04026
Author(s):  
Chuan Kai Jiang ◽  
Lei Nie ◽  
Wen Jia ◽  
Yu Ning Zhong
Keyword(s):  
Thermal Analysis ◽  
Finite Element ◽  
Temperature Distribution ◽  
Temperature Variation ◽  
Finite Element Models ◽  
Distribution Analysis ◽  
Internal Defects ◽  
External Temperature ◽  
Thermal Distribution ◽  
Distinct Temperature

In order to uncover the external manifestations of TSV internal defects, the finite element models of typical internal defects, which were filling missing, axial cavity and end cavity, were established. The thermal analysis was carried out using thermoelectric coupling method. The temperature distribution of TSV with and without defects were obtained. And the temperature variation profiles on the defined paths of TSV layer were also analyzed. The analysis indicated that all the defective TSV showed distinct temperature distribution with the defect-free TSV. Among three typical defects, TSV with filling missing showed the most obvious difference on the temperature distribution and path variation. TSV with end cavity has relatively weak affect and the slightest defect was TSV with axial cavity. Therefore, it could be seen that the external temperature difference caused by the internal defects of TSV could provide effective information for the identification and detection in TSV with internal defects.

Leak Localization Algorithm Applied to Non-Isothermal Liquid Flow in Horizontal Pipelines

2018 ◽  
Author(s):  
Aline Figueiredo ◽  
Carina N. Sondermann ◽  
Rodrigo A. C. Patricio ◽  
Raphael Viggiano ◽  
Gustavo C. R. Bodstein ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Liquid Flow ◽  
Heat Transfer Process ◽  
Isothermal Flow ◽  
Localization Algorithm ◽  
External Temperature ◽  
Oil Pipeline ◽  
Localization Model ◽  
Localization Strategy ◽  
Leak Localization

In the oil industry liquid pipelines are very important for the transport of liquids, particularly in long offshore pipelines. The operation of these oil pipelines is susceptible to the occurrence of leaks in the system. Localizing a leak in a very long oil pipeline is an important piece of information that needs to be obtained before mitigating actions can be taken. These pipelines are usually subject to the temperature gradients that exist in the bottom of the ocean, and the resulting heat transfer process may lead to wax formation and deposition. The single-phase flow that occurs in this type of offshore pipeline that presents one leak point and suffers the effects of an external temperature gradient is numerically simulated in this paper. We consider a one-dimensional mathematical model that includes conservation equations of mass, momentum and energy, and its associated numerical method to calculate the transient liquid flow inside the pipeline. We are particularly interested in testing a leak localization model based upon the intersection of the hydraulic grade lines emanating from the pipeline ends under the influence of a non-zero temperature distribution. This paper proposes to compare the results for a non-isothermal flow with the corresponding isothermal flow to study the influence of the temperature distribution upon the leak localization strategy. The flow that develops along the entire pipeline, upstream and downstream of the leak, strongly affects the pressure gradient and has a significant influence on the location of the leak. Our numerical simulations show results that allow the model sensitivity to be studied by changing the leak magnitude, for a given leak position. From this analysis, we may observe how these parameters affect the pressure gradients along the pipeline that develop upstream and downstream of the leak and the model’s ability to predict the leak location.

X-ray diffraction method for determination of interplanar spacing and temperature distribution in crystals under an external temperature gradient

2015 ◽  
Vol 48 (3) ◽  
pp. 853-856 ◽  
Author(s):  
V. R. Kocharyan ◽  
A. S. Gogolev ◽  
A. E. Movsisyan ◽  
A. H. Beybutyan ◽  
S. G. Khlopuzyan ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Temperature Gradient ◽  
Single Crystal ◽  
Interplanar Spacing ◽  
Diffraction Method ◽  
X Ray Diffraction ◽  
External Temperature ◽  
X Ray ◽  
Spacing Distribution

An X-ray diffraction method is developed for the determination of the distribution of temperature and interplanar spacing in a single-crystal plate. In particular, the temperature and the interplanar spacing differences in two different parts of a quartz single crystal of X-cut are experimentally determined depending on the value of the temperature gradient applied perpendicularly to the reflecting atomic planes (10\bar 11). The temperature distribution along the direction perpendicular to the reflecting atomic planes (10\bar 11) and the interplanar spacing distribution of atomic planes (10\bar 11) are determined as well.

On the thermocapillary motion of partially engulfed compound drops

2009 ◽  
Vol 626 ◽  
pp. 263-289 ◽  
Author(s):  
L. ROSENFELD ◽  
O. M. LAVRENTEVA ◽  
A. NIR
Keyword(s):  
Temperature Gradient ◽  
Volume Ratio ◽  
Thermal Conductivity Ratio ◽  
External Temperature ◽  
Interfacial Tensions ◽  
Thermocapillary Motion ◽  
Physical Conditions ◽  
Thermal Fields ◽  
Induced Motion ◽  
Compound Drops

In this work the thermocapillary-induced motion of partially engulfed compound drops is considered. This phenomenon occurs in many natural and technological processes in which heat is exchanged between such hybrid drops and the medium around them through the interfaces. Two types of thermal fields and the resulting motions are studied; flow induced by an external temperature gradient and spontaneous thermocapillary motion. For the first flow type, it was found that, in general, the motion is induced in the direction of the temperature gradient. However, under certain physical conditions and drops' configuration a motion against the temperature gradient may be observed. In the second case, spontaneous thermocapillary motion, the compound drop moves due to surface tension gradients which result from the geometric non-uniformity of the system. Results are presented for several parameters such as configuration of the compound drop, viscosity, thermal conductivity ratio, the dependence of the various interfacial tensions on temperature and the volume ratio of the phases within the drop.

scholarly journals Temperature Distribution of Railway Tunnels in Winter

2021 ◽  
Vol 21 (1) ◽  
pp. 199-205
Author(s):  
YoonSik Park ◽  
SeHee Lee ◽  
KookHwan Cho
Keyword(s):  
Temperature Distribution ◽  
Influence Factor ◽  
Concrete Slab ◽  
Freezing Temperature ◽  
Tunnel Lining ◽  
Freezing Range ◽  
External Temperature ◽  
Slab Track ◽  
Train Operation ◽  
Tunnel Entrance

The freezing water around the tunnel lining, which is caused by the external temperature during winter, damages portions of tunnel structures, such as the lining and concrete slab track. To investigate the influence of freezing temperature, a total of 50 temperature gauges were installed from the tunnel entrance to 3,270 m. The total length of the tunnel was 8,293 m. The variation in temperature along the tunnel was measured during winter. The correlation between the variation in temperature and the influence of train operation at a speed of 130-150 km/h was analyzed. The duration of the increasing freezing temperature range influenced by train operation was also analyzed and displayed in the results. The results demonstrated that the variation in temperature according to the train operation could be recovered in 30 min. Therefore, when considering the freezing range of a tunnel where trains are travelling at intervals of approximately 30 min, it was judged that the influence factor will be negligible owing to the train operation.

THE ANALYSIS OF THERMAL FIELDS AT THE PRIMARY STAGE OF THE STEAM-ASSISTED GRAVITY DRAINAGE PROCESS

2021 ◽  
Vol 7 (2) ◽  
pp. 27-42
Author(s):  
Alexander Ya. GILMANOV ◽  
Konstantin M. FEDOROV ◽  
Alexander P. SHEVELEV
Keyword(s):  
Temperature Distribution ◽  
Gravity Drainage ◽  
Stage Duration ◽  
Minimum Duration ◽  
Primary Stage ◽  
Steam Assisted Gravity Drainage ◽  
Thermal Fields ◽  
Unbounded Medium ◽  
Well Pattern ◽  
First Time

This article analyzes the temperature distribution in a producer well at the primary stage of the steam-assisted gravity drainage process. The increase in share of hard-to-recover reserves requires using steam-assisted gravity drainage (SAGD). Its successful application, in turn, depends on warming up the inter-well zone, which demands steam circulation in both wells at the primary stage of the process. The duration of this stage affects the transition to oil production and the profitability of the process, which emphasizes the importance of analyzing thermal fields at this stage to assess its duration. The existing research does not allow estimating the temperature in the producer, using the correct formulation of the problem. This paper presents the temperature distribution in a producer for SAGD for classical and chess well patterns for the first time. The aim of the work is to choose a development system for the minimum duration of primary stage of SAGD. For this purpose, the fundamental solution of the non-stationary heat equation for a continuous stationary point source in an unbounded medium is used. The estimation of temperature, at which oil becomes mobile, allows determining the primary stage duration. The authors compare the classical and chess well patterns. In addition, they have obtained the temperature distribution in producer. The results show that classical well pattern provides faster heating of inter-well zone. It is determined that the closest injection well has the greatest influence on the temperature in the producing well.

scholarly journals Distribution and forecast of air temperature in determining of heat output of the district heating substation with heat storage

2019 ◽  
Vol 116 ◽  
pp. 00094
Author(s):  
Michał Turski ◽  
Robert Sekret
Keyword(s):  
Temperature Distribution ◽  
Air Temperature ◽  
Heat Storage ◽  
Control Method ◽  
District Heating ◽  
Current Control ◽  
Heat Output ◽  
External Temperature ◽  
Central Heating ◽  
Water Based

The aim of this article was to determine the energetic effect of adapting the control method of district heating substation to a solution using dispersed heat storage. The current control method of district heating substation uses the equations for regulating the temperature distribution of the installation water based on the value of the external temperature. This control method causes a significant amount of heat not consumed by end users. To adapt the control method to a solution using dispersed heat storage the following values were analyzed: the forecast of external temperature and duration of episodes with the lowest external temperatures on the heat output of the district heating substation based on 63 heating seasons. Obtained results were presented for a district heating substation in Poland. The analysis shows that a temperature of -15°C can be adopted as the reference to determine the expected heat output of the district heating substation. On this basis the demand for heat output for central heating purposes was 406 kW instead of 430 kW. The energetic effect of use dispersed heat storage to compensate the reduced heat output of the district heating substation was 24 kW with a compensation time of 24.2 h.

Conjugate Heat Transfer Simulation of a Radially Cooled Gas Turbine Vane

2004 ◽  
Author(s):  
Bruno Facchini ◽  
Andrea Magi ◽  
Alberto Scotti Del Greco
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Temperature Distribution ◽  
Gas Turbine ◽  
Conjugate Heat Transfer ◽  
Circular Cross Section ◽  
External Temperature ◽  
Turbine Vane ◽  
Heat Transfer Simulation ◽  
The Impact

A 3D conjugate heat transfer simulation of a radially cooled gas turbine vane has been performed using STAR-CD™ code and the metal temperature distribution of the blade has been obtained. The study focused on the linear NASA-C3X cascade, for which experimental data are available; the blade is internally cooled by air through ten radially oriented circular cross section channels. According to the chosen approach, boundary conditions for the conjugate analysis were specified only at the inlet and outlet planes and on the openings of the internal cooling channels: neither temperature distribution nor heat flux profile were assigned along the walls. Static pressure, external temperature and heat transfer coefficient distributions along the vane were compared with experimental data. In addition, in order to asses the impact of transition on heat transfer profile, just the external flow (supposed fully turbulent in the conjugate approach) was separately simulated with TRAF code too and the behaviour of the transitional boundary layer has been analyzed and discussed. Loading distributions were found to be in good agreement with experiments for both conjugate and non conjugate approaches, but, since both pressure and suction side exhibit a typical transitional behavior, HTC profiles obtained without taking into account transition severely overestimate experimental data especially near the leading edge. Results confirm the significant role of transition in predicting heat transfer and, therefore, vane temperature field when a conjugate analysis is performed.

scholarly journals A problem in the theory of heat conduction

1921 ◽  
Vol 100 (704) ◽  
pp. 226-240 ◽  
Keyword(s):  
Heat Conduction ◽  
Temperature Distribution ◽  
Hollow Cylinder ◽  
Main Difficulty ◽  
Uniform Temperature ◽  
External Temperature ◽  
The Law

The first problem discussed in this paper is as follows :— “A long hollow cylinder is immersed in a medium of uniform temperature, and at a certain instant, is brought suddenly to a temperature above that of the medium, for example, by the passage through it of a stream of heated liquid. It is maintained at that temperature, and the temperature distribution in the outside medium at any instant, and the rate of leakage of heat from the cylinder, are required.” The main difficulty arises from the fact that the law of temperature on the surface of separation is arbitrary—we shall suppose, in the first instance, that it is constant. Solutions for the external temperature distribution are apparently known only when the surface has a given initial distribution, which is left to adjust itself without further direct supply of heat.

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