Documents disponibles écrits par cet auteur

Enhancement of saturation boiling of PF-5060 on microporous copper dendrite surfaces / Mohamed S. El-Genk in Journal of heat transfer, Vol. 132 N° 7 (Juillet 2010) 

Public ISBD [article]  in Journal of heat transfer > Vol. 132 N° 7 (Juillet 2010) . - pp. [071501-1/9] Titre : Enhancement of saturation boiling of PF-5060 on microporous copper dendrite surfaces Type de document : texte imprimé Auteurs : Mohamed S. El-Genk, Auteur ; Amir F. Ali, Auteur Article en page(s) : pp. [071501-1/9] Note générale : Physique Langues : Anglais (eng) Mots-clés : Pool  boiling  enhancement  Copper  nanodendrites  Electrochemical  deposition  Electronics  cooling  Dielectric  liquids Index. décimale : 536 Chaleur. Thermodynamique Résumé : Experiments are performed to investigate saturation boiling of degassed PF-5060 dielectric liquid on microporous copper dendrite surface layers deposited on 10×10 mm2 Cu substrates. The electrochemically deposited surface layers are of different thicknesses (145.6 µm, 46.3 µm, and 33.1 µm). The thickest layer gives the best results: the saturation CHF of 25.27 W/cm2 occurs at a surface superheat of only 2.9 K and the maximum nucleate boiling heat transfer coefficient, hMNB, near the end of the fully developed nucleate boiling region, is 8.76 W/cm2 K. In addition, nucleate boiling ensues at a surface temperature slightly above saturation (<0.5 K), with no temperature excursion. The temperature excursions before initiating boiling on the 46.3 µm and 33.1 µm thick Cu nanodendrite surface layers are small (3.7 K and 6 K), corresponding to surface temperatures of ~55.1°C and 57.4°C, respectively. These temperatures are much lower than recommended (85°C) for reliable operation of most silicon electronics and central processor units. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...] [article] Enhancement of saturation boiling of PF-5060 on microporous copper dendrite surfaces [texte imprimé] / Mohamed S. El-Genk, Auteur ; Amir F. Ali, Auteur . - pp. [071501-1/9]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 132 N° 7 (Juillet 2010) . - pp. [071501-1/9] Mots-clés : Pool  boiling  enhancement  Copper  nanodendrites  Electrochemical  deposition  Electronics  cooling  Dielectric  liquids Index. décimale : 536 Chaleur. Thermodynamique Résumé : Experiments are performed to investigate saturation boiling of degassed PF-5060 dielectric liquid on microporous copper dendrite surface layers deposited on 10×10 mm2 Cu substrates. The electrochemically deposited surface layers are of different thicknesses (145.6 µm, 46.3 µm, and 33.1 µm). The thickest layer gives the best results: the saturation CHF of 25.27 W/cm2 occurs at a surface superheat of only 2.9 K and the maximum nucleate boiling heat transfer coefficient, hMNB, near the end of the fully developed nucleate boiling region, is 8.76 W/cm2 K. In addition, nucleate boiling ensues at a surface temperature slightly above saturation (<0.5 K), with no temperature excursion. The temperature excursions before initiating boiling on the 46.3 µm and 33.1 µm thick Cu nanodendrite surface layers are small (3.7 K and 6 K), corresponding to surface temperatures of ~55.1°C and 57.4°C, respectively. These temperatures are much lower than recommended (85°C) for reliable operation of most silicon electronics and central processor units. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...]

On the performance of very high temperature reactor plants with direct and indirect closed brayton cycles / Mohamed S. El-Genk in Transactions of the ASME . Journal of engineering for gas turbines and power, Vol. 132 N° 3 (Mars 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 3 (Mars 2010) . - 07 p. Titre : On the performance of very high temperature reactor plants with direct and indirect closed brayton cycles Type de document : texte imprimé Auteurs : Mohamed S. El-Genk, Auteur ; Jean-Michel Tournier, Auteur Année de publication : 2010 Article en page(s) : 07 p. Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Brayton  cycle  Compressors  Heat  exchangers  Shafts  Turbines Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The performance of very high temperature reactor plants with direct and indirect closed Brayton cycles (CBCs) is compared and the effects of the molecular weight of the CBC working fluid on the number of stages and sizes of the axial flow, single shaft compressor and turbine are investigated. The working fluids considered are helium (4 g/mole), He–Xe, and He–N2 binary mixtures (15 g/mole). Also investigated are the effects of using low and high pressure compressors with intercooling, instead of a single compressor, and changing the reactor exit temperature from 700°C to 950°C on the plant thermal efficiency, the CBC pressure ratio, and the number of stages in and size of the turbomachines. For plants with direct CBCs, the effect of cooling the reactor pressure vessel with He bled off at the exit of the compressor is also investigated. The present analyses are performed for a reactor thermal power of 600 MW, shaft rotation speed of 3000 rpm, and intermediate heat exchanger temperature pinch of 50°C. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ000132000003 [...] [article] On the performance of very high temperature reactor plants with direct and indirect closed brayton cycles [texte imprimé] / Mohamed S. El-Genk, Auteur ; Jean-Michel Tournier, Auteur . - 2010 . - 07 p. Génie Mécanique Langues : Anglais (eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 3 (Mars 2010) . - 07 p. Mots-clés : Brayton  cycle  Compressors  Heat  exchangers  Shafts  Turbines Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The performance of very high temperature reactor plants with direct and indirect closed Brayton cycles (CBCs) is compared and the effects of the molecular weight of the CBC working fluid on the number of stages and sizes of the axial flow, single shaft compressor and turbine are investigated. The working fluids considered are helium (4 g/mole), He–Xe, and He–N2 binary mixtures (15 g/mole). Also investigated are the effects of using low and high pressure compressors with intercooling, instead of a single compressor, and changing the reactor exit temperature from 700°C to 950°C on the plant thermal efficiency, the CBC pressure ratio, and the number of stages in and size of the turbomachines. For plants with direct CBCs, the effect of cooling the reactor pressure vessel with He bled off at the exit of the compressor is also investigated. The present analyses are performed for a reactor thermal power of 600 MW, shaft rotation speed of 3000 rpm, and intermediate heat exchanger temperature pinch of 50°C. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ000132000003 [...]

Subcooled boiling of PF-5060 dielectric liquid on microporous surfaces / Mohamed S. El-Genk in Journal of heat transfer, Vol. 133 N° 8 (Août 2011) 

Public ISBD [article]  in Journal of heat transfer > Vol. 133 N° 8 (Août 2011) . - pp. [081503/1-8] Titre : Subcooled boiling of PF-5060 dielectric liquid on microporous surfaces Type de document : texte imprimé Auteurs : Mohamed S. El-Genk, Auteur ; Amir F. Ali, Auteur Année de publication : 2011 Article en page(s) : pp. [081503/1-8] Note générale : Physique Langues : Anglais (eng) Mots-clés : Subcoled  boiling  Microporous  copper  Electrochemical  deposition  Electronic  cooling  Dielectric  liquids Index. décimale : 536 Chaleur. Thermodynamique Résumé : Presented are the results of experiments that investigated nucleate boiling of PF-5060 on microporous Cu surface layers at saturation and 10 K, 20 K, and 30 K subcooling. The three microporous layers, electrochemically deposited on 10×10 mm2 Cu substrates and investigated herein, are ~139 µm, 171 µm, and 220 µm thick. The critical heat flux increases linearly with increased subcooling, Tsub, at an average rate of 4.5%/K. For the 171 µm thick, Cu microporous surface, saturation boiling CHF of 27.8 W/cm2 increases to 63.25 W/cm2 at Tsub=30 K, while the saturation hMNB of 13.5 W/cm2 K decreases slightly to 12.7 W/cm2 K at Tsub=30 K. The values of the surface superheat, Tsat, at hMNB and CHF increase from 2.0 K and 2.16 K at saturation to 4.2 and 6.42 K at 30 K subcooling. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO00013300 [...] [article] Subcooled boiling of PF-5060 dielectric liquid on microporous surfaces [texte imprimé] / Mohamed S. El-Genk, Auteur ; Amir F. Ali, Auteur . - 2011 . - pp. [081503/1-8]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 133 N° 8 (Août 2011) . - pp. [081503/1-8] Mots-clés : Subcoled  boiling  Microporous  copper  Electrochemical  deposition  Electronic  cooling  Dielectric  liquids Index. décimale : 536 Chaleur. Thermodynamique Résumé : Presented are the results of experiments that investigated nucleate boiling of PF-5060 on microporous Cu surface layers at saturation and 10 K, 20 K, and 30 K subcooling. The three microporous layers, electrochemically deposited on 10×10 mm2 Cu substrates and investigated herein, are ~139 µm, 171 µm, and 220 µm thick. The critical heat flux increases linearly with increased subcooling, Tsub, at an average rate of 4.5%/K. For the 171 µm thick, Cu microporous surface, saturation boiling CHF of 27.8 W/cm2 increases to 63.25 W/cm2 at Tsub=30 K, while the saturation hMNB of 13.5 W/cm2 K decreases slightly to 12.7 W/cm2 K at Tsub=30 K. The values of the surface superheat, Tsat, at hMNB and CHF increase from 2.0 K and 2.16 K at saturation to 4.2 and 6.42 K at 30 K subcooling. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO00013300 [...]