Development of supercritical water heat-transfer correlation for vertical bare tubes

2011 ◽  
Vol 241 (4) ◽  
pp. 1126-1136 ◽  
Author(s):  
Sarah Mokry ◽  
Igor Pioro ◽  
Amjad Farah ◽  
Krysten King ◽  
Sahil Gupta ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Supercritical Water ◽  
Heat Transfer Correlation

Assessment of Computational Tools in Support of Heat-Transfer Correlation Development for Fuel Assembly of Canadian Supercritical Water-Cooled Reactor

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Laurence K. H. Leung ◽  
Yanfei Rao ◽  
Krishna Podila
Keyword(s):  
Heat Transfer ◽  
Fuel Assembly ◽  
Supercritical Water ◽  
Supercritical Pressure ◽  
Heat Transfer Correlation ◽  
Computational Tools ◽  
Experimental Heat ◽  
Experimental Heat Transfer ◽  
Transfer Behavior ◽  
Supercritical Water Cooled Reactor

Experimental data and correlations are not available for the fuel-assembly concept of the Canadian supercritical water-cooled reactor (SCWR). To facilitate the safety analyses, a strategy for developing a heat-transfer correlation has been established for the fuel-assembly concept at supercritical pressure conditions. It is based on an analytical approach using a computational fluid dynamics (CFD) tool and the ASSERT subchannel code to establish the heat transfer in supercritical pressure flow. Prior to the application, the CFD tool was assessed against experimental heat transfer data at the pseudocritical region obtained with bundle subassemblies to identify the appropriate turbulence model for use. Beyond the pseudocritical region, where the normal heat transfer behavior is anticipated, the ASSERT subchannel code also was assessed with appropriate closure relationships. Detailed information on the supporting experiments and the assessment results of the computational tools are presented.

Supercritical Water Heat-Transfer Correlation for Vertical Bare Tubes

2009 ◽  
Author(s):  
Sarah Mokry ◽  
Yevgeniy Gospodinov ◽  
Igor Pioro ◽  
Pavel Kirillov
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Supercritical Water ◽  
Large Set ◽  
Heat Transfer Correlation ◽  
Experimental Dataset ◽  
Forced Convective Heat Transfer ◽  
Normal Heat

This paper presents an analysis of heat transfer to supercritical water in bare vertical tubes. A large set of experimental data, obtained in Russia, was analyzed and an updated heat-transfer correlation for supercritical water was developed. This experimental dataset was obtained within conditions similar to those for proposed SuperCritical Water-cooled nuclear Reactor (SCWR) concepts. Thus, the new correlation presented in this paper can be used for preliminary heat-transfer calculations in SCWR fuel channels. The experimental dataset was obtained for supercritical water flowing upward in a 4-m-long vertical bare tube. The data was collected at pressures of about 24 MPa for several combinations of wall and bulk-fluid temperatures that were below, at, or above the pseudocritical temperature. The values for mass flux ranged from 200–1500 kg/m2s, for heat flux up to 1250 kW/m2 and inlet temperatures from 320 to 350°C. Previous study (Pioro et al., 2008) confirmed that there are three heat-transfer regimes for forced convective heat transfer to water flowing inside tubes at supercritical pressures: (1) Normal heat-transfer regime; (2) Deteriorated heat-transfer regime, characterized by lower than expected heat transfer coefficients (HTCs) (i.e., higher than expected wall temperatures) than in the normal heat-transfer regime; and (3) Improved heat-transfer regime with higher-than-expected HTC values, and thus lower values of wall temperature within some part of a test section compared to those of the normal heat-transfer regime. The HTC data were compared to those values calculated with the Dittus-Boelter and Bishop et al. correlations. The comparison showed that the Bishop et al. correlation represents more closely HTC profiles along the heated length of the tube than the Dittus-Boelter correlation. The latter correlation deviates significantly from experimental data within the pseudocritical range. However, outside the pseudocritical region, the Dittus-Boelter correlation can predict closely experimental HTCs. It should be noted that neither of these correlations can be used for prediction of HTCs within the deteriorated heat-transfer regime. An updated heat-transfer correlation is presented in this paper for forced convective heat transfer in the normal heat-transfer regime to supercritical water in a bare vertical tube. It has demonstrated a good fit (±25%) for the analyzed dataset. This correlation can be used for future comparisons with other independent datasets, with bundled data, for the verification of computer codes for SCWR core thermalhydraulics and for the verification of scaling parameters between water and modeling fluids.

Development of a Heat-Transfer Correlation for Supercritical Water Flowing in a Vertical Bare Tube

2010 ◽  
Author(s):  
Sarah Mokry ◽  
Amjad Farah ◽  
Krysten King ◽  
Sahil Gupta ◽  
Igor Pioro ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Supercritical Water ◽  
Wall Temperature ◽  
Heat Transfer Correlation ◽  
Experimental Dataset ◽  
Forced Convective Heat Transfer ◽  
Bare Tube

This paper presents an analysis of heat-transfer to SuperCritical Water (SCW) in bare vertical tubes. A large set of experimental data, obtained in Russia, was analyzed and a new heat-transfer correlation for SCW was developed. This experimental dataset was obtained within conditions similar to those for proposed SuperCritical Water-cooled nuclear Reactor (SCWR) concepts. Thus, the new correlation presented in this paper can be used for preliminary heat-transfer calculations in SCWR fuel channels. The experimental dataset was obtained for SCW flowing upward in a 4-m-long vertical bare tube. The data was collected at pressures of about 24 MPa for several combinations of wall and bulk-fluid temperatures that were below, at, or above the pseudocritical temperature. The values ranged for mass flux from 200–1500 kg/m2s, for heat flux up to 1250 kW/m2 and for inlet temperatures from 320 to 350°C. Previous studies have confirmed that there are three heat-transfer regimes for forced convective heat transfer to water flowing inside tubes at supercritical pressures: (1) Normal Heat-Transfer (NHT) regime; (2) Deteriorated Heat-Transfer (DHT) regime, characterized by lower than expected Heat Transfer Coefficients (HTCs) (i.e., higher than expected wall temperatures) than in the NHT regime; and (3) Improved Heat-Transfer (IHT) regime with higher-than-expected HTC values, and thus lower values of wall temperature within some part of a test section compared to those of the NHT regime. Also, previous studies have shown that the HTC values calculated with the Dittus-Boelter and Bishop et al. correlations deviate quite substantially from those obtained experimentally. In particular, the Dittus-Boelter correlation significantly over predicts the experimental data within the pseudocritical range. A new heat-transfer correlation for forced convective heat-transfer in the NHT regime to SCW in a bare vertical tube is presented in this paper. It has demonstrated a relatively good fit for HTC values (±25%) and for wall temperature calculations (±15%) for the analyzed dataset. This correlation can be used for supercritical water heat exchangers linked to indirect-cycle concepts and the co-generation of hydrogen, for future comparisons with other independent datasets, with bundle data, as the reference case, for the verification of computer codes for SCWR core thermalhydraulics and for the verification of scaling parameters between water and modeling fluids.

Development of Heat Transfer Correlation for Supercritical Water in Vertical Upward Tubes

2018 ◽  
Vol 40 (8) ◽  
pp. 652-666 ◽  
Author(s):  
Xianliang Lei ◽  
Yumeng Guo ◽  
Weiqiang Zhang ◽  
Huixiong Li ◽  
Liangxing Li
Keyword(s):  
Heat Transfer ◽  
Supercritical Water ◽  
Heat Transfer Correlation
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