Turbulent heat transfer augmentation and friction in periodic fully developed channel flows

Journal Article · Sat Feb 01 04:00:00 EST 1992 · Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States)

DOI:https://doi.org/10.1115/1.2911267· OSTI ID:5126968

Liou, T M; Hwang, J J ^[1]

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1. National Tsing Hua Univ., Hsinchu (Taiwan)

Measurements are presented of the distribution of average friction factors (f) as well as local and average ({ovr Nu}) heat transfer coefficients for fully developed channel flows with two rib-roughened opposite walls. The temperature measurements were made by using both a laser holographic interferometer and thermocouples. In addition, the reattachment length was determined by flow visualization. The Reynolds number (Re) was varied from 5.0 {times} 10{sup 3} to 5.4 {times} 10{sup 4}; the rib pitch-to-height ratios (Pi/H) were 10, 15, 20; and the rib height-to-hydraulic diameter ratios (H/De) were 0.063, 0.081, and 0.106. The detailed results allowed the peaks of heat transfer augmentation and the regions susceptible to hot spots to be located and allowed the relative contribution of the rib surface and the channel wall to the heat transfer augmentation to be determined. Moreover, relative to a smooth duct, the enhancement of both {ovr Nu} and f at various Re, Pi/H, and H/De was documented in detail. Furthermore, compact correlations in terms of Re, Pi/H, and H/De were developed for both {ovr Nu} and f.

• OSTI ID: 5126968
• Journal Information: Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States), Journal Name: Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States) Vol. 114:1; ISSN 0022-1481; ISSN JHTRA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
AUGMENTATION
DUCTS
ENERGY TRANSFER
FLUID FLOW
FRICTION FACTOR
HEAT TRANSFER
INTERFEROMETERS
MEASURING INSTRUMENTS
REYNOLDS NUMBER
TEMPERATURE MEASUREMENT
THERMOCOUPLES
TURBULENT FLOW