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Heat Pipe for Aerospace Applications—An Overview  [PDF]
K. N. Shukla
Journal of Electronics Cooling and Thermal Control (JECTC) , 2015, DOI: 10.4236/jectc.2015.51001
Abstract: The paper presents an overview of heat pipes, especially those used in different space missions. Historical perspectives, principles of operations, types of heat pipes are discussed. Several factors have contributed to the science and technology of the present state-of-Art heat pipe leading to the development of loop heat pipes, micro and miniature heat pipes and micro loop heat pipes. The paper highlights the advancement of heat pipe for hypersonic cruise vehicles, loop heat pipes with higher conductance in 10 K range, heat pipe switches for temperature control of the spacecraft electronics.
Choosing the trenchless renovation methods and trenchless underground methods of pipelines refitting
Jan Ziaja,Rafal Wi?niowski
Acta Montanistica Slovaca , 2006,
Abstract: The authors describe causes of carrier pipe ageing and methods of their inspection and renovation. The technical aspects of choosing the renovation methods are also presented. The paper includes a decision-making flowchart for choosing the carrier pipes renovation.
Onset of Turbulence in Planar and Circular Pipe
L. Jirkovsky,L. Bo-ot
Science Diliman , 2003,
Abstract: A third-order hydrodynamic equation with a molecular structure parameter, obtained through a projection and perturbationformalism from the Liouville equation is applied to circular and planar Poisseuille-Hagen flow. It is shown that there is noprincipal difference in the resulting parabolic velocity profiles as long as the flows remain laminar. However, a difference isnoted in the onset of turbulence in consistency with observations, showing larger stability of the parabolic velocity profilein circular pipe.
Heat Transport Study of the Laminar Heat Pipe Heat Exchanger  [PDF]
Wei-Keng Lin, Ke Chine Liaw, Min-Zen Tsai, Min-Gung Chu
Smart Grid and Renewable Energy (SGRE) , 2012, DOI: 10.4236/sgre.2012.34046
Abstract: The purpose of this experiment is to analyze the performance of the Laminar Heat Pipe Heat Exchanger. The test samples were divided two groups, one is the metal corrugated sheet with heat pipe, and the other is the metal corrugated sheet only. By dipping these two group samples into hot water and to see the thermal image by Infrared thermal imager. The results shown the temperature risen of the sheet with heat pipe was faster than that of the sheet without heat pipe. In addition, the bigger of the temperature difference between hot water temperature and ambient temperature, the quicker of the temperature risen for the metal corrugated sheet, and the temperature of the metal corrugated sheet were homogenous as well. For example, when the water temperature is 30℃, ambient temperature is 20℃, the metal corrugated sheet with heat pipe rise rapidly to 26℃ within 1 minute, while the metal corrugated sheet without heat pipe rise to 22℃ only, this temperature difference would be more obvious with the increasing of the hot water temperature. When the hot water temperature is up to 40℃, the metal corrugated sheet with heat pipe rise rapidly to 31℃ within 1 minute, while the metal corrugated sheet without het pipe is still rise up to 22℃ only. When the hot water temperature is up to 50℃, The metal corrugated sheet with heat pipe rise rapidly to 33℃ within 1 minute, while the sheet without heat pipe still keep at 22℃, the results shown the heat pipe affect the temperature rising speed is obvious, and it also implying heat pipe is a very important parameter for the heat transfer rate of the Laminar Heat Pipe Heat Exchanger.
Rusty pipe syndrome: A case report  [PDF]
Usharani Thota, Vasudeva Murali Machiraju, Venkateswara Rao Jampana
Health (Health) , 2013, DOI: 10.4236/health.2013.51020
Abstract:

Bloody discharge from the breasts in a lactating woman can be caused by various conditions like cracked nipples, mastitis, trauma or ductal papilloma [1]. A physiological condition called rusty pipe syndrome can also cause bilateral bloody discharge in lactating mothers [2].

Integrity Assessment of Pipe System in a Full-Scale Membrane Water Treatment Plant  [PDF]
H. K. Oh, J. Y. Eom, S. H. Kang, H. C. Yoo, Y. J. Kim, D. M. Yoon, J. H. Lim
Journal of Water Resource and Protection (JWARP) , 2014, DOI: 10.4236/jwarp.2014.64038
Abstract:

The pipe system roles as a main bridge between membrane modules and pumps in membrane water treatment plants. Membrane operation modes generally consist of filtration and backwash processes in a normal mode, a pressure decay test as an integrity test and a chemical circulation through pipe system in a cleaning mode. Thus factors effecting on membrane performance should be sufficiently considered before design and operation. This study evaluated flow analysis for vibration diagnostic and evaluation of the fatigue lifetime in the microfiltration system applied for a drinking water treatment plant. Vibration of main membrane pipelines was measured to identify the source of vibration. Also natural frequency and fluid dynamics was calculated by computational fluid dynamics. It showed that maximum magnitude frequencies were at 12 Hz and 22 Hz, respectively at water and air pipeline during filtration and backwash. Backwash process caused mainly vibration on the backwash water pipe. The calculated frequency from analysis of frequency response and CFD was in a good agreement with the measured frequency. Fatigue analysis showed that pipelines were getting little damage caused by vibration. Fatigue lifetime was predicted more than 15 years under the operation condition of daily filtration, and more than 27 years under the operation condition of a daily backwash mode, resulting in minor damage on the pipe lifetime.

Simulation of Average Turbulent Pipe Flow: A Three-Equation Model  [PDF]
Khalid Alammar
Open Journal of Fluid Dynamics (OJFD) , 2014, DOI: 10.4236/ojfd.2014.41005
Abstract: The aim of this study is to evaluate a three-equation turbulence model applied to pipe flow. Uncertainty is approximated by comparing with published direct numerical simulation results for fully-developed average pipe flow. The model is based on the Reynolds averaged Navier-Stokes equations. Boussinesq hypothesis is invoked for determining the Reynolds stresses. Three local length scales are solved, based on which the eddy viscosity is calculated. There are two parameters in the model; one accounts for surface roughness and the other is possibly attributed to the fluid. Error in the mean axial velocity and Reynolds stress is found to be negligible.
Testing of a Low-Cost Loop Heat Pipe Design  [PDF]
Cosimo Buffone
Journal of Electronics Cooling and Thermal Control (JECTC) , 2014, DOI: 10.4236/jectc.2014.41004
Abstract:
This paper presents and describes the test campaign of a low-cost Loop Heat Pipes (LHP) design. LHP have been around for many decades now. Their potential as passive heat transfer devices has been widely demonstrated in numerous both ground- and space-based applications. One of the major disadvantages of LHP is their inherent high manufacturing cost; this is the main factor why LHP are still confined to niche/high end applications such as thermal management of spacecrafts. This paper proposes to use an alternative manufacturing design for the LHP evaporator, which is the main contributor to the overall LHP cost. Preliminary thermal results are also reported and briefly explained. Future work is needed to confirm the promising results discussed in this paper and address fully other issues such as tolerance of this LHP design to vibrations and accelerations typical of space missions.
Pipe Inspection System by Guide Wave Using a Long Distance Waveguide  [PDF]
Riichi Murayama, Kenshi Matsumoto, Kenji Ushitani, Makiko Makiko
Modern Mechanical Engineering (MME) , 2015, DOI: 10.4236/mme.2015.54014
Abstract: In the industrial fields, many high temperature structures that require a non-destructive inspection exist. However, there are currently few sensors that can carry out non-destructive testing in a high temperature environment. In particular, the ultrasonic sensor is normally not used at over 50 degrees Celsius. Also, a special sensor for high temperature is currently available, but there are various constraints; it has not yet reached a level that is useful in industry. Therefore, we have been developing a new sensor system using a long waveguide which can transmit an ultrasonic wave from a long distance. Especially, this study focuses on applying the developed technique to a pipe which is used in a nuclear power plant. Therefore, the best rectangular-shaped waveguide was studied and attempted to be wound around a pipe to be driven by an acoustic source of a guide wave. Finally, the L (0, 2) and T (0, 1)-mode guide waves were successfully detected by optimizing the shape of the opposite edge of the rectangular-shaped waveguide that could detect the reflected signal from an artificial defect machined into a test pipe.
Experimental Analysis of Heat Transfer Behavior inside Heat Pipe Integrated with Cooling Plates  [PDF]
Chen-Ching Ting, Chien-Chih Chen
Engineering (ENG) , 2011, DOI: 10.4236/eng.2011.39118
Abstract: This work used experimental methods to study heat transfer behavior inside a heat pipe and found that heat transfer behavior inside the heat pipe was changed due to its integration with cooling plates. This change caused the heat pipe to have copper-like heat transfer behavior. Experimental performances first built a CPU simulator with maximum heat power 300 W in accordance with the ASTM standard as heat source and measured temperature distribution by using infrared thermography and thermocouple thermometer. Observation of heat transfer behavior inside heat pipe influenced by its integration with cooling plates used color schlieren technique. A commercial CPU heat pipe cooler was also used as reference object in this work. Integration of the heat pipe with cooling plates causes the heat pipe to have the copper-like heat transfer behavior. The results indicate that rebuilding the bare heat pipe’s heat transfer behavior is the best solution for improving cooling efficiency of the heat pipe cooler.
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