Flow instability in vertical upflow under low heat flux conditions

Conference · Fri Jan 01 04:00:00 EST 1993 · Transactions of the American Nuclear Society; (United States)

OSTI ID:6954080

Yang, B W; Dougherty, T; Ouyang, W ^[1]; McAssey, E Jr ^[2]; Smalec, L ^[3]

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1. Columbia Univ., New York, NY (United States)
2. Villanova Univ., PA (United States)
3. Babcock Wilcox Co., Lynchburg, VA (United States)

An experimental and analytical investigation has been conducted to examine Ledinegg flow instability in a heated vertical channel under upflow conditions. Ledinegg instability refers to the condition in which the channel pressure drop increases, due to void production, as the flow rate is decreased. The resulting demand curve (pressure drop versus flow rate) will experience a minimum point. The existence of the minimum point [onset of flow instability (OFI) point] will depend on the competing effects of the bubble rise rate and the bubble-induced frictional loss. The objectives of this program include comparison of upflow and downflow OFI data, development of RELAP model predictions for the experimental conditions, and comparison of the experimental and analytical predictions for the power-limiting threshold below which OFI does not occur.

• OSTI ID: 6954080
• Report Number(s): CONF-931160--
• Conference Information: Journal Name: Transactions of the American Nuclear Society; (United States) Journal Volume: 69
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
BUBBLES
COMPARATIVE EVALUATIONS
COMPUTER CODES
EVALUATION
FLOW RATE
FLUID FLOW
FLUID MECHANICS
HEAT FLUX
INSTABILITY
MECHANICS
PRESSURE DROP
R CODES
VOIDS