Tube rupture analysis

A vapor poeket on the exchanger s low-pressure side can create a cushion that may greatly diminish the pressure transient s intensity. A transient analysis may not be required if sufficient low-pressure side vapor exists (although tube rupture should still be considered as a viable relief scenario). However, if the low-pressure fluid is liquid from a separator that has a small amount of vapor from flashing across a level control valve, the vapor pocket may collapse after the pressure has exceeded the fluid s bubble point. The bubble point will be at the separator pressure. Transient analysis will prediet a gradually inereasing pressure until the pressure reaches the bubble point. Then, the pressure will increase rapidly. For this ease, a transient analysis should be considered. 

API RP-521 reeommends transient analysis for exchangers with wide difference in design pressure (such as cases where the two-thirds rule was not applied) because the pressure in the low pressure side of the exehanger ean spike to a level that exceeds the pressure predicted by a steady state analysis when it is liquid-filled. This pressure spike is due to pressure buildup before the liquid is accelerated out of the low pressure side and/or before the relief device opens fully. API RP-521 recommends that the basis for the tube rupture be a sharp... 

Eluor Daniel has the ability to perform a heat exchanger tube rupture transient analysis consistent with the method referred to in RP-521 ("Model to Predict Transient Consequences of a Heat Exchanger Tube Rupture," by Sumaria et ah). This methodology accounts for effects such as the inertia of the low-pressure liquid, the compressibility of the liquid, the expansion of the exchanger shell or tube chaimels, and the relief valve dynamics. Dynamic simulation can be used to meet the following objectives ... 

Fletcher, C. D., and M. A. Bolander, 1986, Analysis of Instrument Tube Ruptures in Westinghouse 4-Loop PWRs, Rep. NUREG/CR 4672, EGG-2461, Idaho Natl. Eng. Lab., Idaho Falls, ID. (4) Ford, W. D., H. K. Fauske, and S. G. Bankoff, 1971a, Slug Expulsion of Freon-113 by Rapid Depressurization of a Vertical Tube, Int. J. Heat Mass Transfer 14 33-140. (4)... 

This paper summarises the FITTR-IS nuclear hydrogen production system and discusses detection method of heat transfer tube rupture of IHX and system analysis results during IHXTR. 

INPO (1982), Analysis of Steam Generator Tube Rupture Events at Oconee and Ginna, Report 83-030, Institute of Nuclear Power Operations, Atlanta. 

Multiple pressure tube rupture events are BDBAs. In this case, the potential hazards are loss of reactor cavity integrity and damage to the metal structures of the reactor. To define the scope of an MPTR beyond which there is the threat of reactor cavity destruction, it is necessary to perform an analysis of the venting capacity of the system for reactor cavity protection against overpressure. The results of this analysis are needed in assessing the consequences of the BDBA leading to an MPTR. 

If computational analysis shows that the channel tube temperature approaches or exceeds 650°C at any point in time and at any elevation, additional analysis should be carried out using a thermomechanical code. Such analysis takes into account both time dependent variations of thermohydraulic parameters and the characteristics of the tube material together with the changes in the tube rupture parameters. 

Direct bypass of the containment (for example, due to a steam generator tube rupture or to an interfacing systems LOCA which discharges outside the containment) and failure of the containment isolation system should be addressed in the analysis. This would normally be included in the definition of the PDSs. 

The fuel gas to a fired heater is controlled by a BPCS control function (function TIC-1), which throttles a fuel control valve, CV-1, as shown in Figure F-3. A hazard analysis was performed to identify process hazards and to determine whether the safeguards were sufficient to mitigate the process hazards. The team determined that when the heater was firing hard, a low-pass flow through the tubes could result in a high firebox temperature with the potential for tube rupture, furnace fire and structural damage to the furnace. 

XXn-14] FARMER, M.T., SIENICKI, J.J., Analysis of transient coolant void formation during a guillotine-type HX tube rupture event in the STAR-LM system employing a supercritical Brayton cycle, ICONE-12 (12 Int. Conf on Nuclear Engineering, Arlington, April 25-29, 2004), Paper ICONE12-49227. 

Fowler, D.W., T.R. Herndon, R.C. Wahrmund, 1968, an Analysis of Potential Overpressure of Heat Exchanger Shell Due to a Rupture Tube, presented at the American Society of Mechanical Engineers Petroleum Division Conference, September 22-25, 1968. 

Morehouse, J. H. et al., 1983, Value-Impact Analysis of Recommendations Concerning Steam Generator Tube Degradations and Rupture Events, SAIC for NRC/NRR Contract NRC-03-82-131, February. 

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