Numerical simulation on heat transfer characteristic of conical spiral tube bundle

• Published in: Applied thermal engineering Vol. 31; no. 2-3; pp. 284 - 292
• Main Authors: Ke, Yan, Pei-qi, Ge, Yan-cai, Su, Hai-tao, Meng
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.02.2011; Elsevier
• Subjects: Applied sciences; Computational fluid dynamics; Computer simulation; Conical spiral tube; Cross sections; Devices using thermal energy; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fluid flow; Fluids; Heat exchangers (included heat transformers, condensers, cooling towers); Heat transfer; Heat transfer enhancement; Mathematical models; Numerical simulation; Secondary fluid flow; Spirals; Theoretical studies. Data and constants. Metering; Tubes; Heat transfer enhancement; Numerical simulation; Conical spiral tube; Secondary fluid flow; Flow(fluid); Tube bundle; Heat exchanger; Numerical method; Cross section (collision); Heat transfer; Boundary layer
• ISSN: 1359-4311
• DOI: 10.1016/j.applthermaleng.2010.09.008

Conical spiral tubes are universally used in heat transfer enhancement in heat exchangers. The heat transfer characteristic of conical spiral tube bundle was investigated with numerical simulation method. Different grid strategies and boundary layers were used and the results of numerical simulation were verified via the foregoing experiment data with a tolerance less than 5%. The effect of structural parameters on heat transfer characteristic of conical spiral tube was discussed. The fluid flow characteristic inside the tube of different cross sections was also investigated. The results show that the cone angle and cross section have significant effect on tube heat transfer, while the helical pitch has little influence on heat transfer enhancement. The contours of the fluid flow inside the tube indicate that the center of the axial fluid flow offsets to the outer surface of the tube, and the secondary fluid flow is complicated. There exists four independent parts of secondary flow in each cross section and the flow directions are different from each other.