Gian Piero Celata, Maurizio Cumo, Andrea Mariani, Giuseppe Zummo
{"title":"水过冷流动沸腾燃尽区的物理认识","authors":"Gian Piero Celata, Maurizio Cumo, Andrea Mariani, Giuseppe Zummo","doi":"10.1016/S0035-3159(98)80062-7","DOIUrl":null,"url":null,"abstract":"<div><p>The present paper reports the results of a visualization study of the burnout in subcooled flow boiling of water, with square cross-section annular geometry (formed by a central heater rod contained in a duct characterised by a square cross-section). In order to obtain clear pictures of the flow phenomena, the coolant velocity is in the range 3–9 m·s<sup>−1</sup> and the resulting heat flux is in the range 7–13 MW·m<sup>−2</sup>. From video images (single frames were taken with a light exposure of 1 μs) the following general behaviour of vapour bubbles was observed: when the rate of bubble generation is increasing, with bubbles growing in the superheated layer close to the heating wall, their coalescence produces a sort of elongated bubble called a vapour blanket. One of the main features of the vapour blanket is that it is rooted to the nucleation site on the heated surface. Bubble dimensions, as well as those of the hot spots, are given as a function of thermal-hydraulic tested conditions.</p></div>","PeriodicalId":101133,"journal":{"name":"Revue Générale de Thermique","volume":"37 6","pages":"Pages 450-458"},"PeriodicalIF":0.0000,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0035-3159(98)80062-7","citationCount":"15","resultStr":"{\"title\":\"Physical insight in the burnout region of water-subcooled flow boiling\",\"authors\":\"Gian Piero Celata, Maurizio Cumo, Andrea Mariani, Giuseppe Zummo\",\"doi\":\"10.1016/S0035-3159(98)80062-7\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The present paper reports the results of a visualization study of the burnout in subcooled flow boiling of water, with square cross-section annular geometry (formed by a central heater rod contained in a duct characterised by a square cross-section). In order to obtain clear pictures of the flow phenomena, the coolant velocity is in the range 3–9 m·s<sup>−1</sup> and the resulting heat flux is in the range 7–13 MW·m<sup>−2</sup>. From video images (single frames were taken with a light exposure of 1 μs) the following general behaviour of vapour bubbles was observed: when the rate of bubble generation is increasing, with bubbles growing in the superheated layer close to the heating wall, their coalescence produces a sort of elongated bubble called a vapour blanket. One of the main features of the vapour blanket is that it is rooted to the nucleation site on the heated surface. Bubble dimensions, as well as those of the hot spots, are given as a function of thermal-hydraulic tested conditions.</p></div>\",\"PeriodicalId\":101133,\"journal\":{\"name\":\"Revue Générale de Thermique\",\"volume\":\"37 6\",\"pages\":\"Pages 450-458\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1998-06-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1016/S0035-3159(98)80062-7\",\"citationCount\":\"15\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Revue Générale de Thermique\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0035315998800627\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Revue Générale de Thermique","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0035315998800627","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Physical insight in the burnout region of water-subcooled flow boiling
The present paper reports the results of a visualization study of the burnout in subcooled flow boiling of water, with square cross-section annular geometry (formed by a central heater rod contained in a duct characterised by a square cross-section). In order to obtain clear pictures of the flow phenomena, the coolant velocity is in the range 3–9 m·s−1 and the resulting heat flux is in the range 7–13 MW·m−2. From video images (single frames were taken with a light exposure of 1 μs) the following general behaviour of vapour bubbles was observed: when the rate of bubble generation is increasing, with bubbles growing in the superheated layer close to the heating wall, their coalescence produces a sort of elongated bubble called a vapour blanket. One of the main features of the vapour blanket is that it is rooted to the nucleation site on the heated surface. Bubble dimensions, as well as those of the hot spots, are given as a function of thermal-hydraulic tested conditions.