Academic literature on the topic 'Boosted-jet'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Boosted-jet.'

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.

Journal articles on the topic "Boosted-jet"

1

Bhattacherjee, Biplob, Sourav K. Mandal, and Mihoko Nojiri. "Top Polarization from Boosted Jet Substructure." EPJ Web of Conferences 49 (2013): 17007. http://dx.doi.org/10.1051/epjconf/20134917007.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Kagan, Michael, Luke de Oliveira, Lester Mackey, Benjamin Nachman, and Ariel Schwartzman. "Boosted Jet Tagging with Jet-Images and Deep Neural Networks." EPJ Web of Conferences 127 (2016): 00009. http://dx.doi.org/10.1051/epjconf/201612700009.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Klimek, Matthew D. "The time substructure of jets and boosted object tagging." Journal of Physics G: Nuclear and Particle Physics 49, no. 4 (March 18, 2022): 045008. http://dx.doi.org/10.1088/1361-6471/ac446a.

Full text
Abstract:
Abstract We propose the study of the time substructure of jets, motivated by the fact that the next generation of detectors at particle colliders will resolve the time scale over which jet constituents arrive. This effect is directly related to the fragmentation and hadronization process, which transforms partons into massive hadrons with a distribution of velocities. We review the basic predictions for the velocity distribution of jet hadrons, and suggest an application for this information in the context of boosted object tagging. By noting that the velocity distribution is determined by the properties of the color string which ends on the parton that initiates the jet, we observe that jets originating from boosted color singlets, such as Standard Model electroweak bosons, will exhibit velocity distributions that are boosted relative to QCD jets of similar jet energy. We find that by performing a simple cut on the corresponding distribution of charged hadron arrival times at the detector, we can discriminate against QCD jets that would otherwise give a false positive under a traditional spatial substructure-based boosted object tagger.
APA, Harvard, Vancouver, ISO, and other styles
4

Dasgupta, Mrinal, Laís Schunk, and Gregory Soyez. "Jet shapes for boosted jet two-prong decays from first-principles." Journal of High Energy Physics 2016, no. 4 (April 2016): 1–50. http://dx.doi.org/10.1007/jhep04(2016)166.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

ALON, RAZ. "JET RESULTS, JET RECONSTRUCTION, AND UNDERLYING EVENT STUDIES AT CDF." International Journal of Modern Physics E 20, no. 07 (July 2011): 1572–77. http://dx.doi.org/10.1142/s0218301311019891.

Full text
Abstract:
We present recent results of jet studies from the CDF Collaboration. The inclusive jet cross section measurements using different clustering algorithms, dijet production, and vector boson plus jet production measurements, are discussed. We also present the first study of highly boosted and massive jets. The properties of these jets, including the mass of the jet and several other observables, such as angularity and planar flow, are discussed.
APA, Harvard, Vancouver, ISO, and other styles
6

Schramm, Steven. "ATLAS Jet Reconstruction, Calibration, and Tagging of Lorentzboosted Objects." EPJ Web of Conferences 182 (2018): 02113. http://dx.doi.org/10.1051/epjconf/201818202113.

Full text
Abstract:
Jet reconstruction in the ATLAS detector takes multiple forms, as motivated by the intended usage of the jet. Different jet definitions are used in particular for the study of QCD jets and jets containing the hadronic decay of boosted massive particles. These different types of jets are calibrated through a series of mostly sequential steps, providing excellent uncertainties, including a first in situ calibration of the jet mass scale. Jet tagging is investigated, including both not-top-quark vs gluon discrimination as well as W/Z boson, H → bb, and top-quark identification. This includes a first look at the use of Boosted Decision Trees and Deep Neural Networks built from jet substructure variables, as well as Convolutional Neural Networks built from jet images. In all cases, these advanced techniques are seen to provide gains over the standard approaches, with the magnitude of the gain depending on the use case. Future methods for improving jet tagging are briefly discussed, including jet substructure-oriented particle flow primarily for W/Z tagging and new subjet reconstruction strategies for H → bb tagging.
APA, Harvard, Vancouver, ISO, and other styles
7

Kim, Hyo J., Yang S. Park, Gae H. Lee, Kee B. Lee, Hasuck Kim, and Jae S. Kim. "Emission Characteristics of Jet Configurations for Jet-Boosted Glow Discharge Atomic Emission Spectrometry." Microchemical Journal 59, no. 3 (July 1998): 399–412. http://dx.doi.org/10.1006/mchj.1998.1627.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Cacciari, Matteo. "Phenomenological and theoretical developments in jet physics at the LHC." International Journal of Modern Physics A 30, no. 31 (November 5, 2015): 1546001. http://dx.doi.org/10.1142/s0217751x1546001x.

Full text
Abstract:
We review the history of jets in high energy physics, and describe in more detail the developments of the past ten years, discussing new algorithms for jet finding and their main characteristics, and summarising the status of perturbative calculations for jet cross sections in hadroproduction. We also describe the emergence of jet grooming and tagging techniques and their application to boosted jets analyses.
APA, Harvard, Vancouver, ISO, and other styles
9

Chiodini, Gabriele. "Jet Substructure Measurements Sensitive to Soft QCD effects with the ATLAS Detector." EPJ Web of Conferences 192 (2018): 00007. http://dx.doi.org/10.1051/epjconf/201819200007.

Full text
Abstract:
Jet substructure observables are powerful tools for the identification of boosted heavy particles and for probing QCD at different energy scales in proton-proton collisions at the LHC. In this work three recent ATLAS measurements sensitive to soft QCD effects and performed with the use of jet substructures are described. Their are kt splitting scales, soft-drop jet masses and pull-jet angles. Some discrepancies between data and predictions are observed in the non-perturbative regime.
APA, Harvard, Vancouver, ISO, and other styles
10

Kitadono, Yoshio. "Energy profile of b-jet for boosted top quarks." EPJ Web of Conferences 80 (2014): 00027. http://dx.doi.org/10.1051/epjconf/20148000027.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Boosted-jet"

1

Abad, David Romero. "Search for massive resonances decaing into pairs of boosted bosons in missing energy plus jet final state Vs=13 TeV." reponame:Repositório Institucional da UFABC, 2017.

Find full text
Abstract:
Orientador: Prof. Dr. Eduardo de Moraes Gregores
Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Física, 2017.
O Large Hadron Collider (LHC) do CERN foi projetado e construído com o objetivo de proporcionar a observação de fenômenos na fronteira das altas energias. O Compact Muon Solenoide (CMS) é um dos quatros experimentos que observam o resultado das colisões hadrônicas de altas energias geradas pelo LHC, podendo medir com grande precisão diversos parâmetros do Modelo Padrão das interações fundamentais bem como propiciar o descobrimento de novos constituintes da matéria e suas interações. Em sua nova fase de operação, iniciada em junho de 2015 e prevista para durar até 2020, ele vem gerando colisões de prótons a 13 e 14 TeV, propiciando um ambiente de descobertas em regiões do espaço de fase ainda não acessíveis. O objetivo deste trabalho é investigar a possível existência de ressonâncias pesadas que tenham por sinal característico seu decaimento em bósons vetoriais massivos do Modelo Padrão, em particular em um par de bósons vetoriais VZ (V = W, Z). A existência de tais ressonâncias é prevista em muitas extensões do Modelo Padrão, tais como as que preveêm la existência de dimensões extras espaciais ou modelo Simplificados que descrevem novos bósons vetoriais de spin um. Estudaremos o indício da existência de tais ressonâncias analisando os sinais experimentais surgidos quando o bóson V decai em dois jatos hadrônicos e o bóson Z decai invisivelmente em dois neutrinos.
The Large Hadron Collider (LHC) at CERN was designed with the purpose to observe new phenomena on the high energies frontier. The Compact Muon Solenoid (CMS) is one of the four experiments that examine the outcome of hadronic collisions at high energies generated by LHC. It can measure with great accuracy various parameters of the Standard Model of fundamental interactions as well as facilitate the discovery of new constituents of matter and their interactions. In this new stage of operation, initiated in June 2015 and expected to last until 2020, the LHC generates collisions of protons at energies of 13 and 14 TeV, providing an environment of discoveries in regions of phase space still not accessible. The objective of this work is to investigate the existence of heavy resonances which have as characteristic signature, decaying in massive vector bosons of the Standard Model, particularly in a pair of vector bosons VZ (V = W, Z). These kind of resonances are predicted by many extensions of the Standard Model, such as models with extra dimensions or Simplified models that describe new vector bosons of spin one. We will examine the evidence of such resonances by analyzing the experimental signatures that arise when the V boson decays into two jets and the Z boson decays invisibly into two neutrinos.
APA, Harvard, Vancouver, ISO, and other styles
2

Ticse, Torres Royer Edson. "Search for the Higgs boson in the ttH(H -> bb) channel and the identification of jets containing two B hadrons with the ATLAS experiment." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4052/document.

Full text
Abstract:
En juillet 2012, le CERN a annoncé la découverte du boson de Higgs qui est la dernière particule manquante du Modèle Standard (MS). Le boson de Higgs a été observé dans différents canaux. La mesure précise de ses propriétés est maintenant très importante pour rechercher des déviations par rapport au SM. Cette thèse présente une recherche du boson de Higgs produit en association avec une paire de quarks top et se désintégrant en une paire de b quark, le canal ttH(H → bb) , en utilisant les données de collisions proton-proton à √s = 13 TeV, collectées avec le détecteur ATLAS en 2015 et 2016. Ce document détaille en particulier la reconstruction du systéme ttH et la séparation du signal du bruit de fond principal tt + jets. Des études récentes montrent qu'il existe une fraction importante du bruit de fond ttbb avec des jets contenant deux hadrons b. Un nouvel algorithme a été développé pour séparer ces jets des jets contenant un seul b-hadron. La description de cet outil est présenté dans cette thèse
In July 2012, CERN announced the discovery of the Higgs boson, the last missing piece of the Standard Model (SM). The Higgs boson was observed in different channels. Precise measurement of its properties is now very important to investigate for possible deviations from the SM. This thesis presents a search for the Higgs boson produced in association with top quarks and decaying to a b quark pair, the ttH(H→bb) channel, using proton-proton collisions at √s = 13 TeV, collected with the ATLAS detector in 2015 and 2016. This document details in particular the full reconstruction of the ttH(H→bb) system and the discrimination between signal and the main background, tt+jets. The ttbb is a subset of the tt+jets backgrounds recent studies show that there is a large fraction of ttbb events with jets containing two b-hadrons. A new algorithm has been developed to discriminate such jets from single b-hadrons jets. The description of this tool is presented in this thesis
APA, Harvard, Vancouver, ISO, and other styles
3

Schwarz, Dennis [Verfasser]. "Measurements of jet mass, top quark mass and top tagging efficiencies in decays of boosted top quarks at CMS / Dennis Schwarz." Hamburg : Staats- und Universitätsbibliothek Hamburg Carl von Ossietzky, 2020. http://d-nb.info/1229625674/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Cavalli, Noemi. "Misura della massa del quark top usando eventi t\bar{t} selezionati da CMS a 13 TeV nel regime all-jet boosted." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14612/.

Full text
Abstract:
Il presente elaborato riporta una misura della massa del quark top effettuata impiegando dati raccolti tramite il rivelatore CMS a LHC durante il Run del 2016, con energia del centro di massa per le collisioni pp pari a 13 TeV e luminosità integrata di 37.0 fb^(−1). Sono stati studiati i prodotti di decadimento di coppie tt secondo il canale totalmente adronico (all jets) in regime boosted. Tale canale risulta essere caratterizzato dalla presenza di due jet ampi, associati sia al decadimento dei bosoni W che al quark b. Per migliorare la purezza del campione gli eventi candidati sono stati selezionati richiedendo la presenza di quark b in ciascuno di essi. Un'ulteriore richiesta di selezione è stata imposta tramite un'analisi multivariata per aumentare la discriminazione degli eventi di fondo. La misura della massa del quark top è stata ottenuta effettuando un fit di massima verosimiglianza e considerando possibili cause di incertezza sistematica. Il valore finale risulta essere: m_t = 171.9 ± 0.3(stat) ± 1.7(sist) GeV. La misura risulta pertanto consistente con la media mondiale di 173.1 ± 0.6 GeV.
APA, Harvard, Vancouver, ISO, and other styles
5

GEROSA, RAFFAELE ANGELO. "Search for new particles decaying into vector boson pairs at LHC with the CMS detector and prospects for the vector boson scattering at the future High Luminosity LHC." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2015. http://hdl.handle.net/10281/94351.

Full text
Abstract:
This thesis presents a three year work inside the Compact Muon Solenoid (CMS) collaboration, mainly focused on data analysis from proton-proton collisions collected by the Large Hadron Collider (LHC) at a centre of mass energy of 8 TeV (LHC Run-I). My efforts were dedicated to searches for heavy particles decaying into di-boson pairs exploring boosted topologies, where the fragmentation products of hadronically decaying vector bosons overlap in the detector, preventing their identification as resolved jets. Several benchmark scenarios for new physics have been considered, from heavy Standard Model (SM) like Higgs boson to beyond the SM (BSM) extensions of the Higgs sector and massive gravitons predicted by Warped Extra Dimension (WED) models. In order to explore these boosted signatures, I developed specific algorithms to identify boosted vector bosons decaying hadronically (V-jets), which are also applied in other searches for new physics characterized high p_{T} jets originating from W/Z-boson, Higgs boson or top quark decays. These algorithms have been improved and new methods have been tested on detailed simulation, reproducing the conditions of the present data taking (LHC Run-II), and finally commissioned with first 13 TeV collisions. In particular, I performed a semi-leptonic WW search for heavy resonances with 8 TeV data, as well as the combination with other exclusive searches in di-boson final states. With no significant excess observed above the predicted background yield, upper limits have been produced in the context of massive gravitons predicted by Bulk and Randall-Sundrum WED models. Eventually, a model independent re-interpretation of the analysis is also performed. In addition, I developed also a search for SM-like Higgs boson at high mass, in the boosted semi-leptonic WW final state. The analysis is categorised in exclusive jet bins to disentangle the gluon fusion production from the vector boson fusion mode. The result is also interpreted in the context of a BSM heavy Higgs scenario, called electroweak singlet model, which predicts the existence of two Higgs scalars with the mass of the lighter one being around 125 GeV. Upper limits on these models are set through an unbinned fit to the di-boson invariant mass spectrum, where a deviation with a local significance of about 2.5 $\sigma$ has been observed in the VBF category. Eventually, I performed feasibility studies for the Vector Boson Scattering (VBS) in view of the CMS detector upgrade, foreseen for the high luminosity LHC (HL-LHC) data taking. If no evidence for new physics will be observed with Run-II collisions, this rare process would become crucial to search for BSM physics via precision electroweak measurements. Two scattering topologies have been considered: the scattering of same sign W-boson pairs and the fully leptonic WZ boson one. The ultimate goal is to assess the future CMS sensitivity to the longitudinal electroweak scattering, to partial unitarized scenarios and to new physics in the EWSB sector, which is parametrized through anomalies in the vector boson self couplings. In addition, the difference in the performance between the proposed upgraded CMS detector and the present one, which will undergo a strong degradation due to radiation damage, is investigated showing how the upgraded technology allows better performances in all the considered benchmark measurements.
APA, Harvard, Vancouver, ISO, and other styles
6

Dechenaux, Benjamin. "Recherche de résonance lourde dans le spectre de masse invariante top-antitop auprès de l'expérience ATLAS du LHC." Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-01038630.

Full text
Abstract:
La présente thèse constitue le compte rendu de l'analyse menée auprès du détecteur ATLAS du LHC et concernant la recherche de processus de création résonante de nouvelles particules se désintégrant en une paire de quarks top. Elle s'articule principalement autour de la notion de jet de hadrons, dont l'identification et la reconstruction est un enjeu capital pour toute mesure essayant de signer l'apparition de quarks top lors de processus de collisions proton-proton. Après une mise en contexte portant sur une description générale des caractéristiques théoriques et expérimentales que présente la thématique de la détection de jets de hadrons dans le détecteur ATLAS, nous présentons une première tentative de validation de la méthode d'étalonnage hadronique local, dont le but est de corriger ces jets des imprécisions de mesure engendrées par le détecteur. Dans la deuxième partie du document figure l'analyse menée sur les 14~fb$^{-1}$ de données de collisions proton-proton à $sqrt{s} = 8$~TeV, récoltées lors de l'année 2012, à la recherche de l'apparition de processus de création résonante de nouvelle particules extit{lourdes} dans le spectre de masse invariante top-antitop. Pour des particules lourdes, les quarks tops produits lors de la désintégration de ces dernières possèdent une impulsion très grande par rapport à leur masse et la désintégration de tels quarks top conduit souvent à une topologie dans l'état final dite og boostée fg, où le quark top, s'il se désintègre de manière hadronique, est très souvent reconstruit comme un seul jet, de large paramètre de rayon. Le présent travail de thèse propose ainsi une étude préliminaire pour reconstruire et identifier le plus précisément possible ce type de signal, en se basant sur l'étude de la sous-structure des jets de hadrons.
APA, Harvard, Vancouver, ISO, and other styles
7

Dreyer, Torben [Verfasser], and Johannes [Akademischer Betreuer] Haller. "First measurement of the jet mass in events with highly boosted top quarks and studies with top tagging at CMS / Torben Dreyer ; Betreuer: Johannes Haller." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://d-nb.info/1201821339/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Cinca, Diane. "Etude de la production de paires de quarks TOP avec ATLAS au LHC, mesure de la masse du quark TOP." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2011. http://tel.archives-ouvertes.fr/tel-00653792.

Full text
Abstract:
Découvert en 1995 à Fermilab, le quark top est le dernier quark découvert. La mesure de ses propriétés permet de tester les prédictions du Modèle Standard et de contraindre la masse du boson de Higgs. De par ses propriétés, le quark top est aussi un partenaire privilégié dans la recherche de particules de Nouvelle Physique attendues à l'échelle du TeV. Ce travail de thèse, effectué auprès du détecteur ATLAS au LHC, présente les méthodes mises en oeuvre afin de mesurer la masse du quark top dans sa désintégration semileptonique. Différentes méthodes de reconstruction des évènements top sont présentées ainsi qu'une analyse dédiée basée sur les arbres de décision boostés. Ses performances sont quantifiées. La mesure précise de la masse du quark top nécessite une compréhension approfondie de l'échelle en énergie des jets. Deux stratégies sont présentées afin de calibrer les jets légers et les jets issus de quark b à l'échelle partonique. Les performances d'un ajustement cinématique appliqué à la mesure de la masse du quark top sont présentées. Une mesure de la masse du quark top est extraite en utilisant une définition de la masse calibrée à l'échelle partonique.
APA, Harvard, Vancouver, ISO, and other styles
9

Farooque, Trisha. "Search for Heavy Resonances Decaying to Top Quark Pairs in the Boosted All-Hadronic Decay Channel." Thesis, 2013. http://hdl.handle.net/1807/43946.

Full text
Abstract:
Many theories of physics beyond the Standard Model predict the existence of TeV-scale resonances that decay to top quark pairs. This thesis presents a search for such resonances produced in proton-proton collisions at a centre-of-mass energy of 7 TeV at the CERN Large Hadron Collider with 4.7 fb−1 of data collected by the ATLAS detector in 2011. The search is performed in the channel where both top quarks decay hadronically and emerge in highly boosted states, and the collimated decay products of each boosted top quark are reconstructed as a single large jet (a “top quark jet”). A tagging technique based on the distinctive masses and substructures of these top quark jets is used to distinguish them from light quark and gluon jets. The data are found to be consistent with Standard Model predictions, and 95% credibility level upper limits are set on the cross section times branching ratio for leptophobic Z' bosons in a Topcolour model and Kaluza-Klein gluons as predicted by the bulk Randall-Sundrum model. These limits exclude Kaluza-Klein gluons with masses between 1.02 TeV and 1.62 TeV. The substructure of light quark and gluon jets, which form the dominant background to hadronically decaying boosted top quarks, is studied in an auxiliary measurement using 35 pb−1 of data collected by ATLAS during the 2010 run period. The observed substructure of these jets are found to be in good agreement with theoretical predictions.
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Boosted-jet"

1

Marzani, Simone, Gregory Soyez, and Michael Spannowsky. Looking Inside Jets: An Introduction to Jet Substructure and Boosted-object Phenomenology. Springer, 2019.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Boosted-jet"

1

Joshi, Kiran. "Studies and Applications of Jet Vetoing in Boosted Topologies." In QCD Radiation in Top-Antitop and Z+Jets Final States, 103–28. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-19653-4_6.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Maltais, Jean-Nicolas, Michel Meyer, Mathieu Leduc, Guillaume Girault, and Hyacinthe Rollant. "Jet Induced Boosted Suction System for Roof Vent Emission Control: New Developments and Outlooks." In Light Metals 2012, 551–56. Cham: Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-319-48179-1_93.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Maltais, Jean-Nicolas, Michel Meyer, Mathieu Leduc, Guillaume Girault, and Hyacinthe Rollant. "Jet Induced Boosted Suction System for Roof-Vent Emission Control: New Developments and Outlooks." In Light Metals 2012, 551–56. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118359259.ch93.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Boosted-jet"

1

Sunar Cerci, Deniz. "Jet substructure and boosted jet measurements at CMS." In 40th International Conference on High Energy physics. Trieste, Italy: Sissa Medialab, 2021. http://dx.doi.org/10.22323/1.390.0507.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Chapleau, Bertrand. "ATLAS jet measurements, and subjet structure for boosted hadronic objects." In 36th International Conference on High Energy Physics. Trieste, Italy: Sissa Medialab, 2013. http://dx.doi.org/10.22323/1.174.0269.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

RAPPOCCIO, Salvatore. "A new top jet tagging algorithm for highly boosted top jets." In European Physical Society Europhysics Conference on High Energy Physics. Trieste, Italy: Sissa Medialab, 2010. http://dx.doi.org/10.22323/1.084.0360.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Veatch, Jason. "Identification of boosted hadronically decaying particles with jet substructure in ATLAS Run-2." In XXVI International Workshop on Deep-Inelastic Scattering and Related Subjects. Trieste, Italy: Sissa Medialab, 2018. http://dx.doi.org/10.22323/1.316.0104.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Schramm, Steven. "Performance of boosted object and jet substructure techniques in Run 1 and 2 ATLAS data." In 38th International Conference on High Energy Physics. Trieste, Italy: Sissa Medialab, 2017. http://dx.doi.org/10.22323/1.282.1155.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Joshi, Shailesh N., Matthew J. Rau, and Ercan M. Dede. "An Experimental Study of a Single-Device Jet Impingement Cooler With Phase Change Using HFE-7100 and a Vapor Extraction Manifold." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63249.

Full text
Abstract:
There is substantial ongoing research into jet impingement cooling with phase change for high heat flux electronics applications. Higher heat transfer coefficients can be achieved through coolant phase change, although the proper evacuation of the resulting two-phase flow is important as it can affect the overall heat transfer performance of the cooler. In prior work, the accumulation of vapor in a multi-device cooler during the two-phase heat transfer process was shown to cause a build-up of pressure inside the cooler. This increase in pressure is logically related to the position of the cooler inlet and outlet ports with respect to the internal cooling geometry. Such pressure increases lead to an increase in the saturation temperature of the coolant and additional concerns regarding fluid containment. The present study describes a novel two-phase single-device cooler with HFE-7100 as the coolant, where the design allows for efficient removal of vapor from the test-section via a sloped outlet manifold. The performance of the cooler was evaluated using smooth and finned copper heat spreaders. To assess the effectiveness of the vapor extraction manifold, a comparison is made with the performance of a related multi-device cooler. Experimental results show that the single-device design reduces pressure build-up inside the cooler by an order of magnitude from 59 kPa to 7 kPa. A 36% increase in the effective heat transfer coefficient (∼19,000 W/m2K) at 50 W/cm2) was also achieved using the new single-device design with the smooth heat spreader when compared to the multi-device cooler. Additionally, by enhancing the heat spreader surface area with fins, the effective heat transfer coefficient was further boosted to 23,000 W/m2K.
APA, Harvard, Vancouver, ISO, and other styles
7

Briones, Alejandro M., Dave L. Burrus, Timothy J. Erdmann, and Dale T. Shouse. "Effect of Centrifugal Force on the Performance of High-G Ultra Compact Combustor." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-43445.

Full text
Abstract:
A numerical investigation of reacting flows in an advanced high-g cavity (HGC), Ultra-Compact Combustor (UCC) concept is conducted. The high-g cavity UCC (UCC-HGC) design uses high swirl in a circumferential cavity (CC) wrapped around a main stream annular flow. The high swirl is generated through angled CC driver jets. This centrifugal force is varied by changing the CC-to-core air mass flow ratio (ṁcc/ṁcore) and jet inclination angle (αjet) relative to the cavity ring surface, while maintaining the global equivalence ratio (ϕGlobal) constant. Steady, rotational periodic, 3D simulations are performed following a multiphase, Reynolds-averaged Navier-Stokes (RANS), and non-premixed flamelet/progress variable (FPV) approach using a customized FLUENT. Results indicate that under non-reacting flow conditions the driver jets impose a very strong bulk swirl flow within the CC and the mainstream flow does not entrain into the CC. Thus, the maximum g-load is primarily sensitive to ṁcc/ṁcore and secondarily to αjet. However, the g-loads become increasingly more sensitive to the latter at greater ṁcc/ṁcore. Now, under reacting flow conditions, the flame interacts with the flow and the bulk swirl flow is diminished at low ṁcc/ṁcore, while boosted at high ṁcc/ṁcore. The former happens because the flame deflects the incoming driver jet flow, enhancing radial and axial velocity components (through thermal expansion), while diminishing the tangential flow velocity. This, in turn, weakens the g-loads within the CC to below its design g-load operation. On the other hand, at high ṁcc/ṁcore and small αjet the flame is perpendicular to the bulk swirl flow, accelerating the flow tangential velocity and enhancing g-loads above its design operation. Qualitatively, the more and hotter the flame that can be sustained within the CC the shorter the flame length. The converse is also true. Flame length does not appear to be strongly influenced by ṁcc/ṁcore and αjet. Even though g-loads appear to enhance reaction progress variable source (SC) and, consequently, turbulent flame speed, through turbulence this does not necessarily mean that the turbulent flame speed under g-loads is various factors greater than its corresponding turbulent flame speed under 0g’s. As the ṁcc/ṁcore increases the center-peaked radial temperature profile at intermediate αjet starts to deteriorate, whereas the radial temperature profile at low αjet improves. For high αjet, increasing ṁcc/ṁcore has no substantial effect on the exit radial temperature profiles.
APA, Harvard, Vancouver, ISO, and other styles
8

Cyrus, John D., David J. Bents, and David M. Overholt. "A Supercharged Turbojet for High Altitude Atmospheric Science Investigations." In ASME 1999 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/99-gt-106.

Full text
Abstract:
A study was conducted for NASA Dryden Flight Research Center to investigate the viability of developing an externally powered zero stage booster fan to boost the altitude performance of a high altitude turbojet from 80 kft. to over 90 kft., in order to realize a very high altitude subsonic remotely piloted aircraft (RPA) capable of atmospheric science missions. A modified non-airbreathing torpedo engine powers the booster fan. The powered fan is grafted onto an airbreathing turbojet (the General Electric YJ97 jet engine) and is used to supercharge the engine (boost inlet pressure and airflow) at altitudes above its original design limits. The inlet boost keeps the engine operating and delivering thrust, at subsonic speeds, to mission altitudes over 95,000 ft. If this modified engine were grafted back into the air vehicle it was originally designed for (the Viet Nam era AQM-91A Compass Arrow) the modifications would enable the vehicle to increase its maximum altitude from 80,000 ft to over 88,000 ft for periods up to 45 min. With some additional wing area, the aircraft, which is in the 5000 lbm TOGW class, could carry a 500 lbm payload to altitudes over 92,000 kft with an operational radius over 1500 NMi. This study examined a number of candidate component arrangements to realize this fan-boosted propulsion system. Performance was estimated for the subsystem components, the resulting propulsion systems, and the associated RPA. In addition, the study estimated the time and cost to demonstrate/validate this concept in a full-scale propulsion system wind tunnel test program. This paper describes the concept, summarizes the concept selection efforts and performance analysis conducted during the study, and explains the rationale behind this unusual approach. A description of the proposed development and test program, and the cost estimate, lies beyond the scope of this paper.
APA, Harvard, Vancouver, ISO, and other styles
9

MUNGIGUERRA, STEFANO, ANSELMO CECERE, and RAFFAELE SAVINO. "AERO-THERMO-DYNAMIC STUDY OF ULTRA-HIGH- TEMPERATURE CERAMIC COMPOSITES FOR THERMAL PROTECTION SYSTEMS AND ROCKET NOZZLES." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35774.

Full text
Abstract:
The most extreme aero-thermo-dynamic conditions encountered in aerospace applications include those of atmospheric re-entry, characterized by hypersonic Mach numbers, high temperatures and a chemically reacting environment, and of rocket propulsion, in which a combusting, high-pressure, supersonic flow can severely attack the surfaces of the motor internal components (particularly nozzle throats), leading to thermo-chemical erosion and consequent thrust decrease. For these applications, Ultra-High-Temperature Ceramics (UHTC), namely transition metal borides and carbides, are regarded as promising candidates, due to their excellent high-temperature properties, including oxidation and ablation resistance, which are boosted by the introduction of secondary phases, such as silicon carbide and carbon fibers reinforcement (in the so-called Ultra-High- Temperature Ceramic Matrix Composites, UHTCMC). The recent European H2020 C3HARME research project was devoted to development and characterization of new-class UHTCMCs for near-zero ablation thermal protection systems for re-entry vehicles and near-zero erosion rocket nozzles. Within the frame of the project and in collaboration with several research institutions and private companies, research activities at the University of Naples “Federico II” (UNINA) focused on requirements definition, prototypes design and test conditions identification, with the aim to increase the Technology Readiness Level (TRL) of UHTCMC up to 6. Experimental tests were performed with two facilities: an arc-jet plasma wind tunnel, where small specimens were characterized in a relevant atmospheric re-entry environment (Fig.1a), and a lab-scale hybrid rocket engine, where material testing was performed with different setups, up to complete nozzle tests, in conditions representative of real propulsive applications (Fig.1b). The characterization of the aero-thermo-chemical response and ablation resistance of different UHTCMC formulations was supported by numerical computations of fluiddynamic flowfields and materials thermal behavior. The UNINA activities provided a large database supporting the achievement of the project objectives, with development and testing of full-scale TPS assemblies and a large-size solid rocket nozzle.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography