Numerical study on heat transfer of Stirling engine heater tube with rectangular micro-ribs

Abstract

Numerical simulations were carried out to study the heat transfer and friction characteristics for Stirling engine heater tubes with three-dimensional internal extended micro-rib. During the numerical simulations, phase angle in a cycle ranged from 0° to 360°. The results represent that the friction factor (f) increased with micro-rib length (L) and micro-rib height (H) for enhanced tube within the range of parameters in this study. For the micro-rib heat tube of L = 60 mm and H = 0.9 mm, the j was equal to 1.44 and the average Stanton number St was significantly improved up to 1.287 compared to smooth tube, the friction factor f was also increased by almost 2.32. The outlet pressure from 0.7 Mpa to 1 Mpa with the cosine change is presented as the phase angle increases. Therefore the benefits are apparent for micro-rib heat tube in Stirling engine.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work has been supported by the National Natural Science Foundation of China (Grant No. 51866011) and The Natural Science Foundation Project of Inner Mongolia (Grant No. 2017 MS (LH) 0504).