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丁国良教授课题组在International Journal of Refrigeration上发表三篇论文
2009-03-22
International Journal of Refrigeration 2009年第1期和第2期刊出了丁国良教授等人撰写的关于“含油环保制冷工质在5 mm强化管内流动沸腾的压降特性”、“纳米制冷剂沸腾过程中纳米颗粒的迁移特性”和“制冷剂质量分布测试方法”的三篇研究论文。这三篇论文分别如下：
[1] Guoliang Ding, Haitao Hu, Xiangchao Huang, Bin Deng, Yifeng Gao. Experimental investigation and correlation of two-phase frictional pressure drop of R410A–oil mixture flow boiling in a 5 mm microfin tube. International Journal of Refrigeration, 2009, 32 (1): 150-161.
ABSTRACT: This study presents experimental two-phase frictional data for R410A-oil mixture flow boiling in an internal spiral grooved microfin tube with outside diameter of 5 mm. Experimental parameters include the evaporation temperature of 5 oC, the mass flux from 200 to 400 kg/m2s, the heat flux from 7.46 to 14.92 kW/m2, the inlet vapor quality from 0.1 to 0.8, and nominal oil concentration from 0 to 5%. The test results show that the frictional pressure drop of R410A initially increases with vapor quality and then decreases, presenting a local maximum in the vapor quality range between 0.7 and 0.8; the frictional pressure drop of R410A–oil mixture increases with the mass flux, the presence of oil enhances two-phase frictional pressure drop, and the effect of oil on frictional pressure drop is more evident at higher vapor qualities where the local oil concentrations are higher. The enhanced factor is always larger than unity and increases with nominal oil concentration at a given vapor quality. The range of the enhanced factor is about 1.0–2.2 at present test conditions. A new correlation to predict the local frictional pressure drop of R410A-oil mixture flow boiling inside the internal spiral grooved microfin tube is developed based on local properties of refrigerant–oil mixture, and the measured local frictional pressure drop is well correlated with the empirical equation proposed by the authors.
[2] Guoliang Ding, Hao Peng, Weiting Jiang, Yifeng Gao. The migration characteristics of nanoparticles in the pool boiling process of nanorefrigerant and nanorefrigerant–oil mixture. International Journal of Refrigeration, 2009, 32 (1): 114-123.
ABSTRACT: Migration characteristics of nanoparticles in the pool boiling process of nanorefrigerant and nanorefrigerant–oil mixture are fundamental knowledge for the application of nanorefrigerants in refrigeration systems. In this paper, migration characteristics of nanoparticles in the nanorefrigerant–oil mixture as well as in the nanorefrigerant were experimentally studied and numerically simulated. Experimental results show that the migrated mass of nanoparticles in the pool boiling process of both nanorefrigerant and nanorefrigerant–oil mixture, increase with the increase of the original mass of nanoparticles and the mass of refrigerant; the migration ratio decreases with the increase of volume fraction of nanoparticles; the migrated mass of nanoparticles and migration ratio in the nanorefrigerant are larger than those in the nanorefrigerant–oil mixture. A numerical model, which can qualitatively well predict the migrated mass of nanoparticles, was established, and the deviations between the model predictions and experimental data were in the range of 7.7–38.4%.
[3] Guoliang Ding, Xiaokui Ma, Ping Zhang, Weizhe Han, Shinichi Kasahara, Takahiro Yamaguchi. Practical methods for measuring refrigerant mass distribution inside refrigeration system. International Journal of Refrigeration, 2009, 32 (2): 327-334
该论文中的内容是与日本大金公司合作研究的成果。
ABSTRACT:The purpose of this paper is to present methods for measuring refrigerant mass distribution inside a refrigeration system conveniently and accurately. The quasi on-line measurement method (QOMM) was presented for measuring refrigerant mass inside heat exchangers. Compared with the existing liquid nitrogen method (LNM), QOMM can avoid the refrigerant waste and accelerate the measurement process. For measuring refrigerant mass inside the compressor, QOMM was used together with the oil level observation method. The liquid level method (LLM) was used to measure the refrigerant mass inside the accumulator and the receiver. In order to verify the accuracy of the measurement methods, not only the deviation of the measurement method for refrigerant in single component was analyzed, but also the prediction of the total refrigerant charge in an air conditioner was verified. The results showed that the maximal prediction deviation of the refrigerant charge in the whole refrigeration system is 1.7%.