To see the other types of publications on this topic, follow the link: Testis Effect of heat on.
Dissertations / Theses on the topic 'Testis Effect of heat on'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Testis Effect of heat on.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Gao, Jing, and 高晶. "Effect of acupuncture on the spermatogenesis of heat-treated rodent testis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41291001.
Full text
2
Gao, Jing. "Effect of acupuncture on the spermatogenesis of heat-treated rodent testis." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41291001.
Full text
3
Yaeram, Jakrit. "The effect of whole body heating on testis morphology and fertility of male mice." Title page, table of contents and summary only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phj259.pdf.
Full text
4
Narang, Vikas A. "Heat Transfer Analysis In Steel Structures." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-050405-133533/.
Full text
5
Choi, Keum-Ran. "3D thermal mapping of cone calorimeter specimen and development of a heat flux mapping procedure utilizing an infrared camera." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-020205-215634/.
Full textAbstract:
Dissertation (Ph.D.)-- Worcester Polytechnic Institute.Keywords: temperature measurement; heat flux maps; Cone Calorimeter; three-dimensional heat conduction; fire growth models; retainer frame; ceramic fiberboard; edge effect; one-dimensional heat conduction; heat flux mapping procedure; infrared camera; specimen preparation; edge frame; one-dimensional heat conduction model; thermal properties. Includes bibliographical references (p.202-204).
6
Newton, Thomas Russell. "Investigation of the effect of process parameters on the formation of recast layer in wire-EDM of Inconel 718." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22580.
Full text
7
Zabida, Omer Saleh. "The effect of methamphetamine on the blood-testis barrier." University of the Western Cape, 2018. http://hdl.handle.net/11394/6775.
Full textAbstract:
>Magister Scientiae - MScIntroduction The blood-testis barrier (BTB) is formed by tight junctions between adjacent Sertoli cells. The barrier formed by these tight junction helps to create a specialized environment for spermatogenesis and provide an immunological barrier to protect developing germ cells. Methamphetamine (Meth) is known as neurotoxin however, its effects on the male reproductive system, especially on Sertoli cells and, the BTB are not well established. Therefore, this study aimed to determine the effects of Meth on the TM4 mouse testis Sertoli cell line and on the integrity of the BTB permeability. Materials and Methods This study investigated the effect of selected concentrations of Meth (0.1 μM, 1 μM, 10 μM, 20 μM and 100 μM) on TM4 mouse testis Sertoli cell line for 24 until 96 hours, using two treatments: an “acute” study (24 hrs exposure) and a “chronic” study, where treatment occurred on a daily basis over 96 hrs. The following parameters were investigated: viability, cell proliferation, mitochondrial activity, monolayer permeability.
8
Berny, Myriam. "High-temperature tests for ceramic matrix composites : from full-field regularised measurements to thermomechanical parameter identification." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPAST028.
Full textAbstract:
Cette thèse a pour objectif de développer une méthode de mesure de champs par corrélation d’images numériques (CIN) à haute température couplée à des mesures thermiques sur une éprouvette technologique en CMC sollicitée dans des conditions thermiques représentatives d’un environnement moteur et de mettre en place une méthodologie d’identification des propriétés thermiques et thermomécaniques du matériau, en quantifiant à chaque étape de la chaîne les incertitudes associées aux quantités d’intérêt et en les réduisant. Il a pour cela été nécessaire de traiter les défis inhérents à la CIN à chaud, que ce soit au niveau de l’acquisition des images (saturation, perte du contraste) ou de la mesure (artefacts dus à l’effet mirage, aussi appelé "brume de chaleur").Ces travaux ont ainsi donné lieu au développement d’un protocole d’étalonnage d’un banc multi-instrumenté par l’utilisation soit d’une mire in-situ, soit par auto-étalonnage en utilisant l’éprouvette elle-même et son environnement. Les mesures de déplacements 3D surfaciques (approches de stéréocorrélation globales) et les mesures thermiques ont permis de mettre en évidence ce phénomène de brume de chaleur. Des stratégies de régularisation spatiotemporelles des déplacements mesurés ont été proposées et ont permis d’obtenir des résultats satisfaisants (réduction significative des incertitudes de mesure). De même, des approches par réduction de modèles (POD) ont permis de traiter les données thermiques et de quantifier les incertitudes associées aux phénomènes convectifs. Enfin, un algorithme de recalage de modèle éléments finis pondéré sur les données de températures et de déplacements a été implémenté en vue d’identifier un ensemble de propriétés thermiques et thermomécaniques, en tenant compte de la sensibilité de chaque paramètre par rapport aux incertitudes de mesuresThe aim of this thesis is firstly to develop procedures of full-field measurements with Digital Image Correlation (DIC), coupled to thermal measurements, suitable for high-temperature experiments on CMC specimens under thermal conditions representative of an engine environment. Secondly, a methodology is proposed for identifying the thermal and thermomechanical properties of the material, quantifying at each stage of the chain the uncertainties associated with the quantities of interest and strategies to reduce them. It was necessary to deal with the challenges due to high temperatures, especially for DIC, either in terms of acquisition (saturation, loss of contrast) or measurement (artefacts due to the mirage effect, also called "heat haze effect").This work has led to the development of a calibration protocol for a multi-instrumented bench using either an in-situ calibration target or by self-calibration using the specimen itself and its environment. 3D surface displacement measurements (with global stereocorrelation approaches) and thermal measurements have made it possible to highlight the heat haze effect phenomenon. Spatiotemporal regularisation strategies of the measured displacements were proposed and allowed satisfactory results to be obtained (significant reduction of measurement uncertainties). Similarly, model reduction approaches (POD) have been used to process thermal data and quantify the uncertainties associated with convective phenomena. Finally, a weighted Finite-Element Model Updating (FEMU) algorithm on both temperature and displacement data was implemented in order to identify a set of thermal and thermomechanical properties, taking into account the sensitivity of each parameter with regard to measurement uncertainties
9
MIYAKE, KOJI, HATSUKI HIBI, KEISUKE YOKOI, SATOSHI KATSUNO, and MASANORI YAMAMOTO. "THE EFFECT OF VARICOCELECTOMY ON TESTICULAR VOLUME IN INFERTILE PATIENTS WITH VARICOCELES." Nagoya University School of Medicine, 1995. http://hdl.handle.net/2237/16083.
Full text
10
Reed, Daniel Kelvin. "THE EFFECT OF HYPEROXIC GAS MIXTURES ON RECOVERY FROM SHORT-TERM MAXIMAL EXERCISE (VENTILATION, HEART RATE, PH)." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276382.
Full text
11
Sivanantharaja, G. (Geethanchali). "Effect of surface roughness on heat transfer in heat exchanger." Bachelor's thesis, University of Oulu, 2017. http://urn.fi/URN:NBN:fi:oulu-201712143310.
Full textAbstract:
The heat exchanger is a device that transfers heat from one fluid to another or between fluid and the environment. Over the last few decades, the role of heat exchangers has increased in the process of heat recovery and introduction of new energy sources. Surface roughness of heat exchanger wall plays a vital role in the efficiency of heat transfer. Therefore, significance of surface roughness is examined by many researchers applying different shapes of roughness. Roughness is the variation in the height of a surface. It could be either a part of the geometry or due to deposition of undesired materials (which decreases the thermal function of the heat exchanger, increases the pressure drop and could cause corrosion). Dimensionless heat transfer correlations such as Nusselt number provides a clear view about the effect of heat transfer by surface roughness. This thesis combines different Nusselt correlations for distinct shapes of surface roughness and investigates the suitability of them on a test experiment by comparing the values gotten. From this investigation it was clear that the value of Nunner correlation delivers the most reasonable results for a fouled layer formed by means of crystallization. Also the Nusselt correlation by Saini et al. could be more suitable for artificial surface roughness than for a fouled surfaceLämmönvaihdin on laite, joka siirtää lämpöä fluidista toiseen tai fluidin ja ympäristön välillä. Viimeisimpien vuosikymmenten aikana lämmönvaihtimien rooli on kasvanut lämmön talteenottoprosesseissa ja uusien energialähteiden käyttöönotossa. Lämmönvaihtimien pinnankarheudella, jolla tarkoitetaan seinämän pintakuvion korkeuden muutosta verrattuna tasaiseen pintaan, on merkittävä rooli lämmönvaihtimen tehokkuudessa. Pinnankarheuden vaikutusta lämmönsiirtoon onkin tarkasteltu useissa tutkimuksissa. Pinnankarheus voi olla osa lämmönvaihdinrakennetta tai johtua ei haluttujen materiaalien kerrostumisesta pinnalle. Tällöin puhutaan likaantumisesta, joka heikentää lämmönvaihtimen lämmönsiirtoa, lisää painehäviötä ja voi aiheuttaa korroosiota. Dimensiottomat korrelaatiot, kuten Nusseltin luku antavat tietoa pinnankarheuden aiheuttamasta vaikutuksen lämmönsiirtoon. Tässä kandidaatintyössä on tarkasteltu kirjallisuudessa esitettyjä Nusseltin luvun korrelaatioita ja niiden soveltuvuutta eri pinnankarheuden muotoihin sekä tutkittu niiden soveltuvuutta todellisen lämmönvaihtimen tapauksessa. Tästä tutkimuksessa tarkastelluista korrelaatioista Nunnerin korrelaatio soveltui parhaiten likaantuneen lämmönvaihtimen lämmönsiirron tarkasteluun. Sainin ym. korrelaatio arvioitiin soveltuvan paremmin keinotekoisen pinnankarheuden kuin likaantuneen pinnan lämmönsiirron tarkasteluun
12
Edwards, Bobbie. "The Effects of Tests and Praise on Children's Hear-write and See-say Responses." Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5465/.
Full textAbstract:
Four elementary school children were tested on 120 words containing the short e (e.g., ten, pen) and short a (e.g., tan, pan) sounds. Words were tested in the hear-write (H/W) and see-say (S/S) channels. No programmed consequences were scheduled during baseline (BL) tests 1-3. After BL, an error analysis categorized words based on channel error and topography of error. Praise was delivered during tests 4-6 for correct responses. Children's responses were variable within channel and across channels for a majority of words. By the end of the praise phase, there was a decrease in the number of words with errors, for all children in their error word group. Error topographies began to stabilize for some words during praise.
13
Brown, Rhonda K. "The effects of atrial repolarization on exercise-induced ST-segment depression in apparently healthy females." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07112009-040357/.
Full text
14
Yang, Jun. "Effect of non-uniform axial heat-flux distribution on critical heat flux." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/26816.
Full textAbstract:
An experimental study of the effect of axial flux distribution (AFD) on critical heat flux (CHF) was conducted in directly heated tubes at the Freon-equivalent CANDU reactor conditions of interest. CHF measurements were obtained on test sections with four nonuniform AFD profiles as well as a uniform AFD profile using HFC-134a as a test fluid. Each of the non-uniform AFD test sections had a stepped cosine heat flux profile with approximately 16 heat flux steps. The test conditions covered a pressure range of 1662 to 2389 kPa, a mass flux range of 2827 to 4648 kg m-2 s -1 and an inlet quality range of -0.909 to -0.002.
The results showed that the AFD has a strong effect on CHF at high dryout qualities. (Abstract shortened by UMI.)
15
Poirier, Martin. "The Effect of Progressive Heat Acclimation on Change in Body Heat Content." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/26219.
Full textAbstract:
Heat acclimation increases the local heat loss responses of sweating and skin blood flow which is thought to persist for up to 3 weeks post-acclimation. However, the extent to which increases in local heat loss affect whole-body heat loss as a function of increasing levels of heat stress remains unresolved. Using direct calorimetry, we examined changes in whole-body evaporative heat loss (EHL) during progressive increases in metabolic heat production 1) prior to (Day 0), during (Day 7) and following a 14-day heat acclimation protocol (Day 14) – Induction phase, and; 2) at the end of a 1-week (Day 21) and 2-week decay period (Day 28) – Decay phase. Ten males performed intermittent exercise (3 x 30-min (min) bouts of cycling at 300 (Ex1), 350 (Ex2), and 400 watts•meters2 (W•m2) (Ex3) separated by 10 and 20 min rest periods, respectively). During the induction period, EHL at Day 7 was increased at each of the three exercise bouts (Ex1: + 6%; Ex2 +8%; Ex3: +13%, all p≤0.05) relative to Day 0 (EHL at Ex1: 529 W; Ex2: 625 W; Ex3: 666 W). At Day 14, EHL was increased for all three exercise bouts compared to Day 0 (Ex1: 9%; Ex2: 12%; Ex3: 18%, all p≤0.05). As a result, a lower cumulative change in body heat content (ΔHb) was measured at Day 7 (-30%, p≤0.001) and Day 14 (-47%, p≤0.001). During the decay phase, EHL at Day 21 and 28 was only reduced in Ex 3 (p≤0.05) compared to Day 14. In parallel, ΔHb increased by 39% (p=0.003) and 57% (p≤0.001) on Day 21 and Day 28 relative to Day 14, respectively. When Day 28 was compared to Day 0, EHL remained elevated in each of the exercise bouts (p≤0.05). As such, ΔHb remained significantly lower on Day 28 compared to Day 0 (-16%, p=0.042). We show that 14 days of heat acclimation increases whole-body EHL during exercise in the heat which is maintained 14 days post-acclimation.
16
Zhang, Ji. "Geometry effect on post-dryout heat transfer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0013/MQ28469.pdf.
Full text
17
Bhatti, A. R. "Effect of heat treatment on metallic glasses." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236306.
Full text
18
Lim, Jasmine. "Paternal age effect mutations in germ cell development : pathological correlates in normal testis and testicular tumours." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:da034844-3b4e-4bf8-a834-f0dea23e018b.
Full textAbstract:
Pathogenic gain-of-function mutations associated with increased paternal age, albeit harmful to embryonic development, are paradoxically enriched in the normal testis. Evidence from previous studies indicates that these so-called paternal age-effect mutations confer a proliferative advantage to the spermatogonia in which they arise, leading to clonal expansion within the normal testis over time. Recently, spermatocytic seminoma (SS; a rare testicular germ cell tumour that occurs mainly in older men) has emerged as a key link between the processes of somatic and germline mutation (Goriely et al, Nat Genet. 41:1247-52, 2009), suggesting that the proposed clonal expansion events can in some cases lead to testicular tumourigenesis. In this thesis, I have used immunohistochemistry to seek evidence for putative clones of cells in the normal adult testis. To address this, a screening approach was developed using markers chosen from analysis of normal testicular tissues and SS. The ontogeny of OCT2 and SSX expression in human testis, from embryonic development to adulthood, identified distinct subpopulations of spermatogonia at different maturation stages. Together, these data reveal the potential of OCT2 as a novel marker of Adark spermatogonia (human reserve spermatogonial stem cells). In parallel with these observations, two distinct types of SS characterised by differential OCT2 and SSX immunoexpression were identified, providing new evidence for heterogeneity of this tumour. This work provided the backdrop to the detailed immunohistochemical study of normal adult testis by characterising in serial sections the expression of five spermatogonial markers, MAGEA4, SSX, FGFR3, OCT2 and SAGE1, and a proliferation marker, Ki67. Independent sections were screened with predetermined criteria set to identify unusual positively-stained cellular clusters within the seminiferous tubules. Several antigenic combinations previously described in SS were observed in a subset of these clones, suggesting differing genetic origins and a possible link with early events of testicular tumourigenesis. The size (minimum number of cells) of each clonal event was estimated and its correlation with the staining pattern of the molecular markers was investigated. In summary, the data presented in this thesis convincingly identify for the first time the previously hypothesised clonal events in the testis using immunohistochemical markers. My research will pave the way for future work involving genetic analysis of microdissected cells from these putative clones, aimed at identifying the underlying mutational events thought to be present.
19
Picton, S. "The effect of heat-stress on tomato ripening." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233614.
Full text
20
Wagstaff, Marcus James Dermot. "The neuroprotective effect of the heat shock proteins." Thesis, University College London (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267150.
Full text
21
Sazama, Matt. "The effect of vapor permeable versus non-vapor permeable shirts on heat stress." Online version, 2001. http://www.uwstout.edu/lib/thesis/2001/2001sazamam.pdf.
Full text
22
Arjona, Anibal Augusto. "Molecular responses of neonatally heat stressed broilers exposed to acute heat stress." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39965.
Full textAbstract:
Exposure of broiler cockerels to between 35.0 to 37.8 C for 24 hr at 5 days of age increases their survival when exposed to a heat challenge at 6 weeks of age (35.0-37.8 C; RH 50% ). This' phenomenon does not resemble acclimation since the physiological changes known to occur in acclimated birds exposed to heat have not been observed in the neonatally stressed birds. A series of experiments were conducted to elucidate the mechanisms of neonatally induced thermotolerance. In Experiment 1, the erythrocyte protein profile of control and 5 days heated birds prior to and during exposure to acute heat were determined. Prior to juvenile heat exposure no differences in the erythrocytic protein profile of neonatally stressed and control birds were observed at any age (10, 17, 24, 31 and 38 days of age) when maintained under control conditions. However, upon exposure to an acute heat challenge (40.5 C; 52 days of age) temporal and differential expressions of proteins similar in molecular weight to heat shock proteins (HSPs) were observed between the neonatally stressed and control birds. In Experiment 2, the effects of neonatal heat stress at various ages (5, 8, 12, 16 days of age) on the protein synthesis profile of heart, brain (telencephalon, diencephalon, brain stem, cerebellum) and liver tissues during exposure to an acute heat challenge were studied. In addition, body temperature during neonatal heat exposure was monitored. A significant increase in body temperature was observed during neonatal heat stress. A steady increase in the magnitude of the temperature change was noticed up to 12 days of age. Body temperature of birds exposed to neonatal heat at 16 days of age was similar to that of birds heated at 5 days of age.Ph. D.
23
Bridges, Eileen Joan. "The effects of ß-blockers on exercise parameters in heart failure /." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=78329.
Full textAbstract:
Purpose. To examine the outcome of a 6-month treatment with carvedilol or metoprolol on peak and submaximal exercise performance and ventilatory efficiency in patients with heart failure (HF).Methods. 27 patients with HF were randomized to receive either metoprolol or carvedilol for 6 months and compared with 12 healthy controls. Maximal exercise capacity was assessed at baseline and after 6 months with a symptom limited incremental treadmill protocol (RAMP). Submaximal exercise was determined to be the portion of exercise below a respiratory exchange ratio of 1.0. Peak heart rate (HR), oxygen uptake (VO2), and ventilatory equivalent for O2 and CO2 were recorded. The slopes of the VE vs. VCO2, VE vs. VO2 and VE/VCO2 vs. VO2 relationships were calculated for each subject from submaximal values.
Results. Resting HR decreased to similar extent in both treatment groups. There were no other significant changes in resting hemodynamics or ventricular function. Peak VO2 and HR decreased significantly in both treatment groups. Peak VE/VCO2 and submaximal VCO 2 vs. VE slope were not changed significantly after therapy.
Conclusion. beta-blocker treatment with either metoprolol or carvedilol does not decrease the slope of the VCO2 vs. VE relationship. The present observations may suggest that the exaggerated ventilatory response of patients with moderate HF is not mediated by beta-adrenergic receptors.
24
Turgay, Metin Bilgehan. "Effect Of Surface Roughness In Microchannels On Heat Transfer." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610253/index.pdf.
Full textAbstract:
In this study, effect of surface roughness on convective heat transfer and fluid flow in two dimensional parallel plate microchannels is analyzed by numerically. For this purpose, single-phase, developing, laminar fluid flow at steady state and
in the slip flow regime is considered. The continuity, momentum, and energy equations for Newtonian fluids are solved numerically for constant wall temperature boundary condition. Slip velocity and temperature jump at wall boundaries are imposed to observe the rarefaction effect. Effect of axial
conduction inside the fluid and viscous dissipation also considered separately. Roughness elements on the surfaces are simulated by triangular geometrical obstructions. Then, the effect of these roughness elements on the velocity field and Nusselt number are compared to the results obtained from the analyses of flows in microchannels with smooth surfaces. It is found that increasing surface roughness reduces the heat transfer at continuum conditions. However in slip flow regime, increase in Nusselt number with increasing roughness height is observed. Moreover, this increase is found to be more obvious at low rarefied flows. It is also found that presence of axial conduction and viscous dissipation has increasing effect on heat transfer in smooth and rough channels.
25
Joober, Khaled. "The effect of flow geometry on critical heat flux." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6544.
Full textAbstract:
An extensive and systematic literature review on the effect of flow geometry on the Critical Heat Flux (CHF) has been performed. This review covers most of the flow geometries such as tubes, concentric and eccentric annuli, rectangular channels, irregular-shaped channels and bundles. The following geometric parameters have been found to strongly influence the CHF: (i) hydraulic-equivalent diameter, (ii) heated-equivalent diameter, (iii) gap size, (iv) unheated adjacent surface, (v) heated adjacent surface, (vi) curvature, (vii) eccentricity (including bowing), and (viii) channel shape. It is found that some of the geometric effects on CHF depend on the flow conditions and the CHF type. For each geometry the parametric trends have been described, whenever sufficient experimental results are available. A review and assessment of the available prediction methods is conducted. The following trends have been identified in this study: (i) in general the CHF in annuli (concentric and eccentric) is lower than that in tubes, especially for high quality and narrow gaps; (ii) for rectangular channels and irregular-shaped channels, corners can cause a large CHF reduction; (iii) the CHF for concave surface is significantly higher than the CHF for a convex surface; (iv) the effect of gap size in concentric annuli is different for a departure from nucleate boiling (DNB) type CHF and CHF type for the annular flow regime. For the first CHF type reduction in gap size results in a CHF decrease, while for the second CHF type it results in CHF enhancement; and (v) heating the adjacent surface results in a CHF increase. Based on the observed trends, CHF correction factors have been derived for each geometry. Finally, an interim CHF prediction method for subchannels and flow conditions of interest to CANDU$\sp*$ reactors has been proposed. ftn$\sp*$CANDU--CANada Deuterium Uranium, a registered trademark.
26
Stapleton, Jill. "The effect of physical training on body heat regulation." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28141.
Full textAbstract:
Purpose. We evaluated the effects of an eight-week aerobic exercise training program in previously sedentary individuals on whole-body heat balance. Whole-body evaporative (H˙E) and dry (H˙ D) heat loss as well as changes in body heat content (DeltaH b) were measured using simultaneous direct whole-body and indirect calorimetry. It was hypothesized that following the 8-week exercise training program, a more rapid increase in the rate of whole-body heat loss would occur during exercise resulting in a decrease in the change of body heat content by the end of exercise. It was further hypothesized that the rate of decay of whole-body heat loss during recovery would be greater following the exercise training program.
Methods. Ten previously sedentary young adults (7 males, 3 females) underwent an 8-week exercise program. Participants exercised at a university based facilities 4-5 times per week, 30-90 minutes per session, supervised by personnel. Prior to, and after the 8-week training program, subjects underwent an incremental treadmill test to measure their maximal aerobic capacity (V˙O2max). On a subsequent day, they performed 60-90 minutes of cycling at a constant rate of heat production (∼450 W) followed by 60 minutes of recovery, in a calorimeter at 30°C and 15% relative humidity. Core temperature [esophageal; (Tes), rectal (Tre ) and aural canal (Tau)], mean skin temperature, skin blood flow (SkBF), local sweat rate (LSR), mean arterial pressure (MAP), and heart rate (HR) were measure at baseline and at 2 min, 5 min, 8 min, 12 min, 15 min, 30 min, 45 min, 60 min, and 90 min intervals for the exercise and post-exercise recovery periods.
Results. No significant difference in the rate of total heat loss (H˙L=H˙E+H˙D) was observed during exercise. As a result, the average DeltaHb was similar for the pre- (+441+/-89 kJ) and post-training (+430+/-118 kJ) 60-min exercise bout (p=0.385). Although the absolute changes in Tes (p=0.060), Tre (p5≤0.05) and Tau (p≤0.05) were lower at rest post-training, no differences in the relative change from baseline was measured during exercise. Local sweat rate and SkBF were elevated during exercise however the relative changes from baseline were similar pre- to post-training. A 12% increase in V˙O2max was measured after the 8-week training program (p≤0.05). This was paralleled by a decrease in heart rate throughout exercise (p=0.004).
Conclusion. Although physical training resulted in improvements in cardiorespiratory function as evidenced by increases in V˙O2max and reduced HR response during exercise, these adaptations did not result in an improvement in the capacity for heat dissipation during exercise.
27
Ferizaj, Drilon, and Mohamad Kassem. "Effect of nanofluids on thermal performance of heat pipes." Thesis, KTH, Energiteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148074.
Full textAbstract:
A relatively new way for utilizing the thermal performance of heat pipes is to use nanofluids as working fluids in the heat pipes. Heat pipes are effective heat transfer devices in which the nanofluid operates in the two phases, evaporation and condensation. The heat pipe transfers the heat supplied in e.g. a laptop, from the evaporator to condenser part. Nanofluids are mixtures consisting of nanoparticles (e.g. nano-sized silver particles) and a base fluid (e.g. water). The aim of this bachelor’s thesis has been to examine the effect of nanofluids on heat pipes on the subject of temperature parameters and thermal resistance in the heat pies, through findings in literature and an applied model. The study, based on literature and an applied model, found that higher particle conductivity and higher concentration of nanoparticles consequently decrease the thermal resistance in the heat pipes, resulting in an enhanced thermal performance of the heat pipes with nanofluids as working fluids. It is however concluded that difficulties in finding the optimal synthesis of nanofluids, the concentration level of nanoparticles and the filling ratio of nanofluids in heat pipes, set bounds to the commercial use of nanofluids in heat pipes. It is suggested that, in order to enhance the heat transfer performance of nanofluids in heat pipes, to conduct further research concerning e.g. synthesis of nanofluids and concentration level of nanoparticles in nanofluids.
28
Kleiven, Thomas J. (Thomas John). "Effect of gas path heat transfer on turbine loss." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/112466.
Full textAbstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 117-118).
This thesis presents an assessment of the impact of gas path, i.e., streamtube-to-streamtube, heat transfer on aero engine turbine loss and efficiency. The assessment, based on the concept of mechanical work potential [19], was carried out for two model problems to introduce the ideas. Three-dimensional RANS calculations were also conducted to show the application to realistic configurations. The first model problem, a constant area mixing duct, demonstrates the importance of selecting a fluid component loss metric appropriate to the purpose of the overall system in which the component resides. The phenomenon of thrust increase due to mixing is analyzed to show that system performance can increase even though there is a loss of thermodynamic availability. Gas path heat transfer affects mechanical work potential, and thus turbine loss, through a mechanism called thermal creation [19]. The second model problem, an inviscid heat exchanger, illustrates how thermal creation is due to enthalpy redistribution between flow regions with different local Brayton efficiency. Heat transfer across a static pressure difference, or between gases with different specific heat ratios, can cause turbine efficiency to increase or decrease depending on the direction of the heat flow. Three-dimensional RANS calculations have also been interrogated to define and determine the thermal creation, and thus the losses, in a modern two-stage cooled high pressure turbine. At representative engine operating conditions the effect of thermal creation was a 0.1% decrease in efficiency, with the thermal creation accounting for 1% of the overall lost work. Introducing coolant flow into the main gas path increased the loss from thermal creation in the first stage by 84% and decreased the loss from thermal creation in the second stage by 8%.
by Thomas J. Kleiven.
S.M.
29
Underwood, David Scott. "Effect of heat release on streamwise vorticity enhanced mixing." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/47390.
Full text
30
Kim, Jun-Pill. "LAND-USE PLANNING AND THE URBAN HEAT ISLAND EFFECT." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1253215365.
Full text
31
Ivester, David Newell. "Heat exchanger modeling and optimization in the triple-effect absorption cycle." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/16076.
Full text
32
Tapia, Daniel Felipe Sempértegui. "Análise experimental do efeito da geometria da seção transversal e do desempenho de fluidos de reduzido GWP na ebulição convectiva em canais de dimensões reduzidas." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/18/18147/tde-02022017-152135/.
Full textAbstract:
A presente tese trata da análise experimental do efeito da geometria da seção transversal do canal e do desempenho de refrigerantes de reduzido GWP (Global Warming Potential) durante a ebulição convectiva em canais de reduzidas dimensões. A tese inclui ainda um estudo extenso e crítico da literatura sobre métodos de previsão da perda de pressão e do coeficiente de transferência de calor, e sobre estudos experimentais em canais não-circulares e de refrigerantes com reduzido GWP na ebulição convectiva em canais de dimensões reduzidas. Resultados para o coeficiente de transferência de calor e perda de pressão durante a ebulição convectiva foram obtidos para canais com geometrias de seção circular, quadrada e triangular para o refrigerante R134a. Nos testes utilizou-se canais com perímetros internos similares obtidos a partir da conformação de um tubo com diâmetro interno igual a 1,1 mm. No caso do canal circular, dados foram também levantados para os HFOs R1234ze(E) e R1234yf e o hidrocarboneto R600a, fluidos com reduzido GWP. Ensaios foram executados para amplas faixas de fluxos de calor e velocidades mássicas, temperaturas de saturação de 31 e 41°C e títulos de vapor entre 0 e 0,95. Aspectos relacionados aos efeitos da geometria e do fluido refrigerante foram minuciosamente investigados através da análise paramétrica dos resultados. Com base na comparação do banco de dados coletado com os métodos de previsão disponíveis na literatura, constatou-se que estes proporcionam previsões satisfatórias apenas para condições experimentais especificas. Portanto, novos métodos de previsão da perda de pressão e do coeficiente de transferência de calor foram desenvolvidos com base nos dados levantados no presente estudo. Os métodos propostos preveem satisfatoriamente o banco de dados do presente estudo e resultados independentes disponíveis na literatura. Adicionalmente, com base nos resultados levantados, verificou-se que dissipadores de calor baseados em multi-microcanais com canais de seção triangular apresentam desempenho superior comparados a dissipadores com canais quadrados e circulares.The present thesis concerns an experimental study on the effects of cross-sectional geometry and low GWP refrigerants on the thermal-hydraulic performance for convective boiling inside micro-scale channels. Experimental results for heat transfer coefficient and pressure drop gradient during convective boiling were obtained for circular, square and triangular channels for the fluid R134a. The evaluated channels present the same external perimeter and equivalent diameters of 1.1, 0.977 and 0.835 mm, respectively. In the case of the circular geometry, experimental results were also acquired for the HFOs R1234ze(E) and R1234yf and the hydrocarbon R600a (isobutane), which are fluids with low GWP and null ODP. Experiments were performed for a wide range of heat fluxes and mass velocities, saturation temperatures of 31 and 41°C and vapor qualities up to 0.95. The experimental data were carefully analyzed and discussed based on a parametrical analysis focusing on the effect of the cross-sectional geometry and the working fluid. Subsequently, the experimental data were compared against the most quoted predictive methods from literature. In general, it was verified that none of the predictive methods were able to accurately capture the experimental trends of the overall database. So, new predictive methods for the pressure drop and heat transfer coefficient were developed based on the broad database obtained in the present study. The proposed methods provided satisfactory results not only for the experimental database used for its development, but also for independent databases collected in the literature. Additionally, based on the data obtained in the present study and a performance analysis taken into account pressure drop, heat transfer coefficient and the channel packing factor, triangular cross sectional geometry is recommended for heat sinks.
33
Zahlan, Hussam. "Flow obstacle effect on film boiling heat transfer with uniform and non-uniform axial heat flux." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28143.
Full textAbstract:
An experimental investigation of the effects of axial flux distribution (AFD) and obstacles on film-boiling heat transfer was performed in a vertical tube using HFC-134a as coolant. The following parameters were examined: (1) Axial flux profiles (uniform, inlet-peak and outlet-peak), (2) Flow-blockage ratios (12% and 24%), (3) Obstacle pitches (150 mm and 300 mm), (4) Obstacle shapes (blunt and round).
Test conditions covered the pressure 1665 and 2389 kPa (water-equivalent value: 10 and 14 MPa), a mass-flux range from 1395 to 3575 kg.m-2.s -1 (water-equivalent value: 2000 to 5000 kg.m-2.s -1) and an inlet-fluid temperature range from 30 to 70°C (water-equivalent value: 229 to 324°C). Film-boiling temperature measurements were recorded for all possible heat-flux levels, up to a limiting surface temperature of 240°C to avoid Freon decomposition. Inside wall temperature distributions of the obstacle-equipped test sections were compared against those of a reference bare tube at similar flow conditions.
Flow obstacles were found to have a significant influence on film-boiling heat-transfer. Film-boiling wall temperatures along the test section were reduced significantly by decreasing the obstacle pitch, by increasing the obstacle size and by using a blunt instead of streamline-shaped obstacle.
The effect of AFD on film-boiling heat transfer is noticeable in the developing film-boiling region and can be attributed mainly to the variation in critical heat flux (CHF) occurrence. However, the AFD effect appears to be less obvious in the fully developed film-boiling region.
Since the literature suggested that the single-phase pressure-loss coefficient of the flow obstructions could be an important parameter in correlating the film-boiling heat-transfer enhancement, this parameter was also measured and correlated.
Previously derived prediction methods for obstacle-enhanced film-boiling heat transfer did not provide satisfactorily agreement with the data; therefore, a new prediction method was derived to predict the film-boiling heat-transfer augmentation for uniform AFD tubes. The new equation accounts for the enhancement in film-boiling heat transfer due to turbulence generated by (i) liquid-film termination at the dryout point and (ii) the upstream flow obstructions. The new correlation was applied to non-uniform AFD data. It was concluded that (i) this new prediction method is also applicable to non-uniform AFD tubes, (ii) the new prediction method has the correct asymptotic trends and (iii) single-phase pressure-loss coefficients cannot be used directly to predict the heat-transfer enhancement for both blunt and rounded obstacles.
34
Al-Waaly, Ahmed. "The effect of heat transfer on temperature measurement and its applications to study microchannel heat sinks." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/6781/.
Full textAbstract:
Analytical, numerical and experimental analyses have been performed to investigate the effects of thermocouple wire electrical insulation on the temperature measurement of a reference surface. Two diameters of K-type thermocouple, 80μm and 200μm, with different exposed stripped wire lengths (0 mm, 5mm, 10mm, 15mm and 20mm) were used to measure various surface temperatures (4oC, 8oC, 15oC, 25oC and 35oC). Measurements were made when the thermocouple probe is in direct contact with the surface and the wires are extended vertically and exposed to natural convection from outside environment. Experimental results confirmed that the thermal effect from the electrical insulation on temperature measurement was within -0.5oC and therefore it can be neglected. Moreover, the experimental results agree well with those obtained by both the analytical and numerical methods and further confirm that the diameter of the thermocouple has an impact on the temperature measurement. Analytical results of the thermocouple wire with insulation confirm that there is no specific value for the critical radius and the rate of heat flux around the thermocouple wire continuously increases with the wire radius even when this is larger than the critical radius. Experimental and numerical analyses have been performed to investigate the heating impact of using thermocouples for the temperature measurement of small volumes of cold water. Two sizes of K-type thermocouple have been used: 80μm and 315μm to measure the temperature of the cold water inside a small chamber while the thermocouple wires were extended vertically in the outside environment. For this study, the chamber temperature was adjusted to 4oC. The results show that the heating effect of the thermocouple decreases for the greater depth measurements and this effect is eliminated when the thermocouple junction is close to the chamber bottom surface. The increase in the thermal resistance between the bottom surface and the thermocouple junction raises the heating effect of the thermocouple impact. Moreover, the exposed length of thermocouple wires to the environment has no effect over a specific length where the wire end temperature is equal to that of the environment. Experimental and numerical analyses have been carried out to study the effect of using subchannels in heat sink to minimise the effect of hotspots generated on a chip circuit. Two devices of heat sink – with and without subchannels – were fabricated in order to investigate this effect. The first device was manufactured with a normal parallel channel while the second one was designed to extract more heat by dividing the main channels above the hotspot into two subchannels. A hotspot heat flux (16.7×104 [W/m2]) was applied at the centre of the channels while a uniform heat flux (4.45×104 [W/m2]) was applied at upstream and downstream of the channels. Five mass flow rates have generated under gravity force to investigate the performance of devices under different operating conditions. The results showed the maximum surface temperature was reduced by 4oC the temperature uniformity was improved. Moreover, thermal resistance was reduced by 25% but the pumping power was increased as a result of the presence of the subchannels.
35
Hayes, Mark. "The effect of progressive heat acclimation on games players performing intermittent-sprint exercise in the heat." Thesis, University of Brighton, 2014. https://research.brighton.ac.uk/en/studentTheses/5d460be8-1826-4a96-ac35-9c07c6943e6d.
Full textAbstract:
Intermittent-sprint performance is reduced in hot environments and the impairment occurs without significant difference in metabolic responses to exercise. Reductions in cerebral blood flow and voluntary activation occur with hyperthermia and neuromuscular impairment has been posited to explain decreased performance in the heat. Heat acclimation is used to minimise heat mediated performance impairment, yet traditional protocols may limit adaptation. The purpose of this thesis was to examine the efficacy of a novel progressive heat acclimation model for games players performing intermittent-sprint exercise in the heat and to examine if this method can ameliorate neuromuscular fatigue following exercise of this type.
36
Williams, Winifred Elizabeth. "HEAT TRANSFER IN THE MICROCIRCULATION." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275277.
Full text
37
Cassel, Stanley David. "The effect of increasing length on the overall conductance and capacitance of long heat pipes." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/19589.
Full text
38
Gidugu, Praveen. "Effect of adding a regenerator to Kornhauser's MIT "two-space" test rig." Cleveland, Ohio : Cleveland State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=csu1212595450.
Full textAbstract:
Thesis (M.S.)--Cleveland State University, 2008.Abstract. Title from PDF t.p. (viewed on July 9, 2008). Includes bibliographical references (p. 100-103). Available online via the OhioLINK ETD Center. Also available in print.
39
MIYAKE, KOJI, HATSUKI HIBI, and MASANORI YAMAMOTO. "EFFECT OF ALBUMIN ON PROLUMINAL MOVEMENT OF 3H-ANDROGEN INTO SEMINIFEROUS AND EPIDIDYMAL TUBULES AND ANDROGEN BINDING IN THE INTERSTITIUM OF THE TESTIS AND EPIDIDYMIS AFTER PERIFUSION WITH FLUID CONTAINING ALBUMIN." Nagoya University School of Medicine, 1994. http://hdl.handle.net/2237/16075.
Full text
40
Martin, Andrew. "Measurement of heat strain in firefighters." Thesis, Queensland University of Technology, 1990. https://eprints.qut.edu.au/35956/1/35956_Martin_1990.pdf.
Full textAbstract:
A comparative study of six different fire-fighting clothing ensembles to determine the heat stress
imposed on the wearer was conducted. Physiological indicators of heat strain were monitored while
subjects performed set tasks for up to 30 minutes in controlled environments. The differences between
ensembles was considered. For each ensemble, six subjects performed set tasks in two controlled environments for 30 minutes or until one of a set of termination criteria was met. In the first environment subjects stepped at a set rate
in 40°C dry bulb and 60% humidity conditions. A number of weights, pre-determined to work the subject
at a set level of the individual's Heart Rate Increase Capacity, were carried. In the second environment
subjects lifted bricks at a set rate in front of two 1500 W radiators in 30°C and 60% conditions. Dry bulb
temperature, Wet Bulb Globe Temperature, and humidity were monitored to ensure consistency of test
conditions. A control test with light clothing was performed before the suit testing. Subjects were partially acclimatised prior to testing. Physiological indicators of strain (mean skin temperature, heart rate, blood pressure, and body fluid loss) were monitored and differences between ensembles considered. Skin temperature was calculated from a weighted average of measurements at 6 sites (chest, back, cheek, thigh, calf, and upper arm). Thermocouples (#32 gauge T-type) were attached to the skin with Leukoplast adhesive tape and the temperatures were recorded using a Fluke digital thermometer (sensitivity of 0.1°C) after every minute
of work.
Heart rate was stored every 15 seconds with one monitor and a backup monitor stored the rate at
every heart beat. Body fluid loss and amount of fluid absorbed by the clothing were found by weighing
nude subjects and clothing before and after testing. Scales accurate to 1 O g were used. Final systolic
and diastolic blood pressures were compared to resting values using an automatic monitor. Perceived views of the subjects were also obtained using a questionnaire.
Heart rate showed a steady cyclic increase during each test. Skin temperature rose in the hot environment and partially recovered in the moderate environment also producing a cyclic increase. The subjects lost from 600 g to 1200 g of fluid in each test. Systolic B.P. consistently increased and diastolic B.P. on average decreased. The ranks of the suits obtained were similar for all the measured parameters and the questionnaire. Skin temperature and heart rate clearly showed differences between the ensembles.
41
Vaitekunas, David A. "An investigation of the effect of flow obstructions on critical heat flux, pressure drop and heat transfer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0020/NQ57073.pdf.
Full text
42
Arambakam, Raghu. "MODELING EFFECT OF MICROSTRUCTURE ON THE PERFORMANCE OF FIBROUS HEAT INSULATION." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3212.
Full textAbstract:
Heat insulation is the process of blocking the transfer of thermal energy between objects at different temperatures. Heat transfer occurs due to conduction, convection, or radiation, as well as any combination of these three mechanisms. Fibrous insulations can completely suppress the convective mode of heat transfer for most applications, and also help to reduce the conductive and radiative modes to some extent. In this study, an attempt has been made to computationally predict the effects of microstructural parameters (e.g., fiber diameter, fiber orientation and porosity) on the insulation performance of fibrous materials. The flexible simulation method developed in this work can potentially be used to custom-design optimal multi-component fibrous insulation media for different applications. With regards to modeling conductive heat transfer, a computationally-feasible simulation method is developed that allows one to predict the effects of each microstructural parameter on the transfer of heat across a fibrous insulation. This was achieved by combining analytical calculations for conduction through interstitial fluid (e.g., air) with numerical simulations for conduction through fibrous structures. With regards to modeling radiative heat transfer, both Monte Carlo Ray Tracing and Electromagnetic Wave Theory were implemented for our simulations. The modeling methods developed in this work are flexible to allow simulating the performance of media made up of different combinations of fibers with different materials or dimensions at different operating temperatures. For example, our simulations demonstrate that fiber diameter plays an important role in blocking radiation heat transfer. In particular, it was shown that there exists an optimum fiber diameter for which maximum insulation against radiative transfer is achieved. The optimum fiber diameter is different for fibers made of different materials and also depends on the mean temperature of the media. The contributions of conduction and radiation heat transfer predicted using the above techniques are combined to define a total thermal resistance value for media with different microstructures. Such a capability can be of great interest for design and optimization of the overall performance of fibrous media for different applications.
43
North, Travis. "Experimental and analytical study of time varying electrical fields and their effect on convective boiling heat transfer /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1426090.
Full text
44
Balci, Hamza. "Specific heat and nernst effect of electron-doped cuprate superconductors." College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/217.
Full textAbstract:
Thesis (Ph. D.) -- University of Maryland, College Park, 2004.Thesis research directed by: Physics. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
45
Sarikaya, Onur Turgay. "Analysis Of Heat Treatment Effect On Springback In V-bending." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610182/index.pdf.
Full textAbstract:
Aluminum based alloys have wide area of usage in automotive and defense industry and bending processes are frequently applied during production. One of the most important design criteria of bending processes is springback, which can be basically defined as elastic recovery of the part during unloading. To overcome this problem, heat treatment is generally applied to the workpiece material to refine tensile properties.
In this study, the effect of heat treatment on springback characteristics of aluminum studied both numerically by using finite element analysis and experimentally. For this purpose, two different materials are selected and various heat treatment procedures are considered. The aluminum sheets having thickness of 1.6 mm, 2 mm and 2.5 mm are bent to 60˚
, 90&
#730
and 120&
#730
. The von Mises stress distributions, plastic strain values and punch load values and comparison of the numerical and experimental results are also given.
46
Churi, Asawari Shreeniwas. "Effect of heat shock on hilA expression in Salmonella Typhimurium." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1490.
Full textAbstract:
The effect of heat shock was observed on the expression of hilA in Salmonella
Typhimurium by creating a fluorescence-based reporter strain of Salmonella and by realtime
reverse transcriptase polymerase chain reaction (RT-PCR).
The hilA gene in Salmonella is known to play an important role in its pathogenesis.
hilA is known to be activated when the bacteria encounter stress-inducing conditions. A
number of factors have been identified that affect hilA expression, such as, pH,
osmolarity, oxygen tension. When Salmonella enter their warm-blooded hosts, they
encounter an increase in temperature. Therefore, heat is another stressor that is
encountered by Salmonella during infection of their hosts.
A fluorescence-based strain of Salmonella was created to study the effect of heat
shock. The gene for green fluorescent protein (gfp) was placed under the control of the
promoter of hilA on a plasmid. This plasmid was used to transform Salmonella cells to
create a fluorescent strain. In this strain, when the hilA promoter is activated, gfp is
transcribed, which encodes the green fluorescent protein. This protein can be measured
by a fluorescence assay. The results of this study indicated that at 45ºC, hilA is activated.
RT-PCR was used to look at hilA expression at different temperature. The results of this
study indicated that, compared to 37ºC, higher temperatures like 45ºC and 55ºC
significantly activate hilA.
47
Kiflemariam, Robel. "Heat-Driven Self-Cooling System Based On Thermoelectric Generation Effect." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2281.
Full textAbstract:
This research entails the first comprehensive and systematic study on a heat-driven, self-cooling application based on the thermoelectric generation effect. The system was studied using the first and second laws of thermodynamics to provide a solid and basic understanding of the physical principles governing the system. Multiphysics equations that relate heat transfer, fluid dynamics and thermoelectric generation are derived. The equations are developed with increasing complexity, from the basic Carnot heat engine to externally and internally irreversible engines. A computational algorithm to systematically use the fundamental equations has been presented and computer code is implemented based on the algorithm.
Experiments were conducted to analyze the geometric and system parameters affecting the application of thermoelectric based self-cooling in devices. Experimental results show that for the highest heat input studied, the temperature of the device has been reduced by 20-40% as compared to the natural convection case. In addition, it has been found that in the self-cooling cases studied, convection thermal resistance could account for up to 60% of the total thermal resistance.
A general numerical methodology was developed to predict steady as well as transient thermal and electrical behavior of a thermoelectric generation-based self-cooling system. The methodology is implemented by using equation modeling capabilities to capture the thermo-electric coupled interaction in TEG elements, enabling the simulation of major heating effects as well as temperature and spatial dependent properties. An alternative methodology was also presented, which integrates specialized ANSI-C code to integrate thermoelectric effects, temperature-dependent properties and transient boundary conditions. It has been shown that the computational model is able to predict the experimental data with good accuracy (within 5% error). A parametric study has been done using the model to study the effect of heat sink geometry on device temperature and power produced by TEG arrays.
In addition, a dynamic model suited for integration in control systems is developed. Therefore, the study has shown the potential for a heat driven self-cooling system and provides a comprehensive set of tools for analysis and design of thermoelectric generation.
48
Shahin, Gus A. "The effect of pulsating flow on forced convective heat transfer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ39881.pdf.
Full text
49
Shurkian, Omer M. "The effect of laundering and heat exposure on apparel fabrics." Thesis, University of Manchester, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488300.
Full text
50
Yaeram, Jakrit. "The effect of whole body heating on testis morphology and fertility of male mice / by Jakrit Yaeram." Thesis, 2002. http://hdl.handle.net/2440/21887.
Full text