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R513A在水平管內(nèi)沸騰換熱及壓降特性的實(shí)驗(yàn)研究

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中圖分類號(hào):TK123;TK124 文獻(xiàn)標(biāo)志碼:A

Experimental study on boiling heat transfer and pressure drop characteristics of R513A inside horizontal tubes

ZHANG Qing1, HUANG Lihao12, ZHANG Jiani3, TAO Leren12,ZHU Tianyi1, CHEN Jianhong1 (1.SchoolofEnergyandPowerEngineering, UniversityofShanghai forScienceandTechnology,Shanghai2oo93,Chind; 2.Shanghai Key Laboratory of Multiphase Flow and Heat Transferin Power Engineering, Shanghai 2Oo093,China; 3. Shanghai Institute of Quality Inspection and Technical Research, Shanghai 2oo2l4, China)

Abstract: The growing problem of global warming in the refrigeration industry requires the replacement

Citation: ZHAQi,HUALaoHAJanal.Expetaludyatraeandpresudaracteriso1Ainside horizontal tubes[J]. Journal of University ofShanghai for Science and Technology,2025,47(2): 139-147.

of existing refrigerants and further enhancement of heat transfer eficiency in heat exchangers. The boiling heat transfer characteristics ofR513A in the horizontal smooth tubes and internally ribbed tubes with outer diameter 9.52, 12.70mm were experimentally investigated to analyze the mechanism of changes in heat transfer coeficients and pressure drops by heat flux, tube diameter, mass flux and saturation temperature. The results show that the boiling heat transfer coefficient increases and then decreases with the increase of heat flux. The disturbance of refrigerant in the 9.52mm smooth tube is more intense, and the heat transfer coefficient is increased by 13.91%~19.77% compared with that of the 12.70mm tubes. The pressure drop in the 9.52mm tubes is 1.4~3.8 times that of the 12.70mm tubes. Both the increase in saturation temperature and the increase in mass flux contribute to the heat transfer coeffcient. It is easier to reach the local drying point at low mass fluxes, when the boiling heat transfer coefficient decreases sharply. The Cooper and Liu-Winterton correlations were compared to predict the heat transfer coefficients. Before the drying out, both of them can predict the flow boiling heat transfer characteristics of R513A in the horizontal smooth tube very well. After the drying out, the Liu-Winterton correlation is more accurate, with mean absolute deviation of 18.53% and 28.36% before and after the drying out, respectively.

Keywords: R5l3A; flow boiling; internally ribbed tube; heat transfer coefficient; pressure drop

目前我國(guó)冷水(熱泵)機(jī)組主要采用的制冷劑為 Rl34a 、R22和 R407C 。(剩余12385字)

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