scholarly journals Thermal testing of the light pipe prototype

2019 ◽  
Vol 39 (3) ◽  
pp. 283-291
Author(s):  
Ayodeji Omishore ◽  
Miloš Kalousek ◽  
Petr Mohelnik
Keyword(s):  
Temperature Distribution ◽  
Infrared Thermography ◽  
Infrared Radiation ◽  
Thermal Testing ◽  
Temperature Profiles ◽  
Pipe System ◽  
Light Pipe ◽  
Potential Problems ◽  
System Temperature ◽  
Head Temperature

A light pipe prototype with a concentrating mirror parabolic head was tested for temperature profiles. The purpose of the testing was to find maximal temperature and estimate potential problems for overheating in the position of the pipe installation into roof structures. Infrared thermography monitoring of the light pipe prototype and temperature measurements give overview about the light pipe system temperature distribution. It was proven that the light pipe head temperature was increased for more than 100°C in thermally insulated structure under intensive infrared radiation.

High-speed isotachophoresis. Analytical aspects of the steady-state longitudinal temperature profiles

1979 ◽  
Vol 44 (3) ◽  
pp. 841-853 ◽  
Author(s):  
Zbyněk Ryšlavý ◽  
Petr Boček ◽  
Miroslav Deml ◽  
Jaroslav Janák
Keyword(s):  
Steady State ◽  
Temperature Distribution ◽  
Electric Field ◽  
Field Intensity ◽  
Electric Field Intensity ◽  
Minor Component ◽  
Physical Models ◽  
Temperature Profiles ◽  
Longitudinal Temperature ◽  
Continuous Character

The problem of the longitudinal temperature distribution was solved and the bearing of the temperature profiles on the qualitative characteristics of the zones and on the interpretation of the record of the separation obtained from a universal detector was considered. Two approximative physical models were applied to the solution: in the first model, the temperature dependences of the mobilities are taken into account, the continuous character of the electric field intensity at the boundary being neglected; in the other model, the continuous character of the electric field intensity is allowed for. From a comparison of the two models it follows that in practice, the variations of the mobilities with the temperature are the principal factor affecting the shape of the temperature profiles, the assumption of a discontinuous jump of the electric field intensity at the boundary being a good approximation to the reality. It was deduced theoretically and verified experimentally that the longitudinal profiles can appreciably affect the longitudinal variation of the effective mobilities in the zone, with an infavourable influence upon the qualitative interpretation of the record. Pronounced effects can appear during the analyses of the minor components, where in the corresponding short zone a temperature distribution occurs due to the influence of the temperatures of the neighbouring zones such that the temperature in the zone of interest in fact does not attain a constant value in axial direction. The minor component does not possess the steady-state mobility throughout the zone, which makes the identification of the zone rather difficult.

scholarly journals Temperature distribution analysis of different technologies of PV modules using infrared thermography

2018 ◽  
Vol 49 ◽  
pp. 00044 ◽  
Author(s):  
Slawomir Gulkowski ◽  
Natalia Zytkowska ◽  
Piotr Dragan
Keyword(s):  
Temperature Distribution ◽  
Infrared Thermography ◽  
Power Production ◽  
Distribution Analysis ◽  
Copper Indium Gallium Diselenide ◽  
Pv Systems ◽  
Copper Indium ◽  
Long Time ◽  
High Level ◽  
Continuous Power

Photovoltaic systems are designed to operate for a very long time according to the modules’ warranty that guarantees at least of 80% of the nominal power production after 20 years of use. In order to assure the continuous power production with a high level for a long time, thermographic analysis should be performed to detect incipient anomalies in individual modules and junction boxes. This safe, convenient and noncontact method allows carrying out the inspection for working system without any contact with live wiring and without disconnecting the PV systems. Temperature distribution of the module surface can reveal many different types of anomalies, i.e. hot spots caused by local shading, microcracking or cell breakage. This paper shows the results of the infrared thermography analysis of the operating PV systems consisting of different technological modules: polycrystalline silicon (pc-Si), copper indium gallium diselenide (CIGS) and cadmium telluride (CdTe). The average working temperature of each different kind of technological module as well as overheated areas were investigated in this study. Temperature of the MC4 connectors was also analysed.

Measurement of Grinding Temperature of Ceramics Using Infrared Radiation Pyrometer with Optical Fiber

1992 ◽  
Vol 114 (3) ◽  
pp. 317-322 ◽  
Author(s):  
T. Ueda ◽  
K. Yamada ◽  
T. Sugita
Keyword(s):  
Surface Layer ◽  
Temperature Distribution ◽  
Optical Fiber ◽  
Infrared Radiation ◽  
Grinding Temperature ◽  
Radiation Pyrometer ◽  
Fluoride Fiber ◽  
Grinding Power

The grinding temperature in the surface layer of a ceramic workpiece was measured using an IRP (infrared radiation pyrometer) connected by means of an optical fiber. Two types of optical fiber were employed: fluoride fiber and chalcogenide fiber. Si3N4, SiC, and Al2O3 were used as the work materials. The output waves of I.R.P. of Si3N4 and Al2O3 appear as curves with many peaks which are related to the infrared energy emitted from the cutting grains, but that of SiC shows no peaks at all. The highest grinding temperature was obtained in the case of Si3N4 whose grinding power is the largest of these three materials. The temperature distribution in the surface layer of the ceramics was much different from that of the steel.

scholarly journals An Experimental Investigation of the External Wind Effects on the Ceiling Temperature Distribution of Fire-Induced Thermal Flow in a Corridor Connected to a Compartment

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1826
Author(s):  
Bei Cao ◽  
Xiaodong Zhou ◽  
Yubiao Huang ◽  
Yuan Zheng ◽  
Kai Ye ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Temperature Distribution ◽  
Wind Velocity ◽  
Shielding Effect ◽  
Temperature Profiles ◽  
Building Structures ◽  
Thermal Flow ◽  
Ceiling Temperature ◽  
Higher Temperature

Fire-induced thermal flow is the greatest threat to trapped people and the heat-resistant quality of building structures. This paper presents an experimental investigation of the effects of external wind on the ceiling temperature distribution of fire-induced thermal flow in a one-sixth scale corridor connected to a compartment. In the experiments, the fire source was placed in the compartment with hot thermal flow spilled into the connected corridor. The heat release rate (HRR) was changed from 10 to 20 kW and the external wind velocity was changed from 0 to 2.09 m/s. The ends of the corridor could be adjusted to be fully or partially open to the environment with dam-boards arranged at the ends of the corridor. An effective corridor HRR, Qcorridor, was defined to account for the amount of the spilled plume into the corridor. Results show that the temperature under the ceiling changed in a non-monotonic way with wind velocity: it first increased and then decreased with wind velocity. It was revealed that the dam-boards at the corridor opening had an evidently shielding effect, leading to higher temperature compared to the fully open environment. Finally, uniform correlations are proposed for predicting the attenuation law of ceiling temperature profiles in corridors for different wind conditions.

scholarly journals A Pilot Study of Infrared Thermography Based Assessment of Local Skin Temperature Response in Overweight and Lean Women during Oral Glucose Tolerance Test

2019 ◽  
Vol 8 (2) ◽  
pp. 260 ◽  
Author(s):  
Bushra Jalil ◽  
Valentina Hartwig ◽  
Davide Moroni ◽  
Ovidio Salvetti ◽  
Antonio Benassi ◽  
...  
Keyword(s):  
Pilot Study ◽  
Glucose Tolerance ◽  
Oral Glucose Tolerance Test ◽  
Infrared Thermography ◽  
Glucose Tolerance Test ◽  
Tolerance Test ◽  
Oral Glucose ◽  
Temperature Profiles ◽  
Oral Glucose Tolerance ◽  
Overweight Subjects

Obesity is recognized as a major public health issue, as it is linked to the increased risk of severe pathological conditions. The aim of this pilot study is to evaluate the relations between adiposity (and biophysical characteristics) and temperature profiles under thermoneutral conditions in normal and overweight females, investigating the potential role of heat production/dissipation alteration in obesity. We used Infrared Thermography (IRT) to evaluate the thermogenic response to a metabolic stimulus performed with an oral glucose tolerance test (OGTT). Thermographic images of the right hand and of the central abdomen (regions of interests) were obtained basally and during the oral glucose tolerance test (3 h OGTT with the ingestion of 75 g of oral glucose) in normal and overweight females. Regional temperature vs BMI, % of body fat and abdominal skinfold were statistically compared between two groups. The study showed that mean abdominal temperature was significantly greater in lean than overweight participants (34.11 ± 0.70 °C compared with 32.92 ± 1.24 °C, p < 0.05). Mean hand temperature was significantly greater in overweight than lean subjects (31.87 ± 3.06 °C compared with 28.22 ± 3.11 °C, p < 0.05). We observed differences in temperature profiles during OGTT between lean and overweight subjects: The overweight individuals depict a flat response as compared to the physiological rise observed in lean individuals. This observed difference in thermal pattern suggests an energy rate imbalance towards nutrients storage of the overweight subjects.

Influence of Thermal Radiation on the Temperature Distribution in a Semi-Transparent Solid

1979 ◽  
Vol 101 (1) ◽  
pp. 76-80 ◽  
Author(s):  
D. W. Amlin ◽  
S. A. Korpela
Keyword(s):  
Temperature Distribution ◽  
Nonlinear Partial Differential Equations ◽  
Alternating Direction Method ◽  
Temperature Profiles ◽  
Rectangular Region ◽  
Differential Approximation ◽  
First Order ◽  
Alternating Direction ◽  
Plane Slab ◽  
Good Agreement

The importance of radiation on the temperature distribution in a semi-transparent solid is reported. The first-order differential approximation of radiation is combined with conduction analysis to investigate the temperature profiles in a plane slab and a rectangular region. The coupled nonlinear partial differential equations are solved numerically by either a standard implicit or an implicit alternating direction method. Results obtained for opaque boundaries are in good agreement with exact formulations found in the literature. An extension to partially transparent boundaries is made and results presented.

Thermal Aspects in Resistance Welding of Thermoplastic Composites

2003 ◽  
Author(s):  
Darko Stavrov ◽  
Harald E. N. Bersee
Keyword(s):  
Temperature Distribution ◽  
Power Level ◽  
Resistance Welding ◽  
Thermoplastic Composites ◽  
Transient Temperature ◽  
Temperature Profiles ◽  
Stainless Steel Mesh ◽  
Type K ◽  
Glass Fiber Reinforced ◽  
Set Up

This paper presents a comprehensive experimental study on the thermal aspects in resistance welding of thermoplastic composites. A special test set-up was developed to perform the experiments. Glass fiber reinforced polyetherimide was the material used for manufacturing the welding specimens. Stainless steel mesh was used for production of heating elements. The temperature distribution was monitored using type-K thermocouples connected to a data acquisition system. The main objective of the study was investigating a possible solution for the edge effect. Temperature profiles over the weld length and over the weld width were monitored. The focus was on the transient temperature profiles at the edges of the weld. The temperature distribution through the weld thickness was also monitored. The influence of factors like insulation and power level was investigated. Finally, conclusions are drawn and options for improving the temperature distribution and modification of the models are being discussed.

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