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F. L. Eisinger – One of the best experts on this subject based on the ideXlab platform.
Acoustically induced structural fatigue of piping systemsJournal of Pressure Vessel Technology-transactions of The Asme, 1999Co-Authors: F. L. Eisinger, J. T. FrancisAbstract:
Piping systems handling high-pressure and high-velocity steam and various process and hydrocarbon gases through a pressure-reducing device can produce severe Acoustic Vibration and metal fatigue in the system. It has been previously shown that the Acoustic fatigue of the piping system is governed by the relationship between fluid pressure drop and downstream Mach number, and the dimensionless pipe diameter/wall thickness geometry parameter. In this paper, the devised relationship is extended to cover Acoustic fatigue considerations of medium and smaller-diameter piping systems.
ELIMINATING AIR-FLOW-INDUCED Acoustic Vibration IN COAL PULVERIZERSJournal of Fluids and Structures, 1998Co-Authors: F. L. EisingerAbstract:
A novel method is presented here for eliminating Acoustic Vibration within coal pulverizers. The method emerged from the study of an Acoustic Vibration which developed within the casing of a coal pulverizer at low to medium loads. The Vibration was characterized by an Acoustic quarterwave driven by swirling air-flow of parallel high velocity air-jets issuing from a rotating multi-air port arrangement. By converting the single frequency excitation energy of the air-jets into turbulent energy, utilizing a new air port design with strongly interacting (colliding) air-jets, the Vibration was eliminated. The theoretical background and results of the pre-and post-modification operational tests are presented.
designing piping systems against Acoustically induced structural fatigueJournal of Pressure Vessel Technology-transactions of The Asme, 1997Co-Authors: F. L. EisingerAbstract:
Piping systems adapted for handling fluids such as steam and various process and hydrocarbon gases through a pressure-reducing device at high pressure and velocity conditions can produce severe Acoustic Vibration and metal fatigue in the system. It has been determined that such Vibrations and fatigue are minimized by relating the Acoustic power level (PWL) to being a function of the ratio of downstream pipe inside diameter D 2 to its thickness t 2 . Additionally, such Vibration and fatigue can be further minimized by relating the fluid pressure drop and downstream Mach number to a function of the ratio of downstream piping inside diameter to the pipe wall thickness, as expressed by M 2 Δp = f(D 2 /t 2 ). Pressure-reducing piping systems designed according to these criteria exhibit minimal Vibrations and metal fatigue failures and have long operating life.
Robert E. Sullivan – One of the best experts on this subject based on the ideXlab platform.
Further Evidence for Acoustic Resonance in Full Size Steam Generator and Tubular Heat Exchanger Tube BanksVolume 4: Fluid-Structure Interaction, 2009Co-Authors: Frantisek L. Eisinger, Robert E. SullivanAbstract:
In the previous publications by Eisinger, F.L., Francis, J.T., and Sullivan, R.E., 1996, “Prediction of Acoustic Vibration in Steam Generator and Heat Exchanger Tube Banks”, ASME Journal of Pressure Vessel Technology, Vol. 118, pp. 221–236 and Eisinger, F.L. and Sullivan, R.E., 1996, “Experience with Unusual Acoustic Vibration in Heat Exchanger and Steam Generator Tube Banks”, Journal of Fluids and Structures, Vol. 10, pp. 99–107, prediction criteria for Acoustic Vibration or Acoustic resonance were formulated utilizing flow and Acoustic parameters derived from operating steam generator tube banks. Various parameters were used in those formulations, including the dominant parameter MΔp where M is the Mach number of the crossflow through the tube bank and Δp is the pressure drop through the tube bank. Here we present further evidence derived from operating experience of full size steam generator and tubular heat exchanger tube banks of which 19 experienced Acoustic Vibration or Acoustic resonance and 27 experienced no Vibration or no Acoustic resonance within the operating flow range. The present data show that the decisive parameter predicting the Acoustic Vibration or Acoustic resonance of a tube bank is the Acoustic particle velocity. The Acoustic particle velocity separates the Acoustically vibrating banks from those non-vibrating very clearly. The behavior is demonstrated graphically showing the dimensionless Acoustic particle velocity as a function of input energy parameter MΔp, Mach number M, Reynolds number Re and also Helmholtz number He = MS where S is the Strouhal number. This finding indicates that the Acoustic particle velocity criterion shall be used in conjunction with the previously used criteria as the basis for the prediction of Acoustic resonance in full size steam generator and tubular heat exchanger tube banks.Copyright © 2009 by ASME
Prediction of Acoustic Vibration in Steam Generator and Heat Exchanger Tube BanksJournal of Pressure Vessel Technology, 1996Co-Authors: F. L. Eisinger, J. T. Francis, Robert E. SullivanAbstract:
Criteria are formulated for the development of Acoustic Vibration in transverse Acoustic modes in steam generator tube banks, based on flow and Acoustic parameters. Theoretical predictions are validated against available in-service data for nonvibrating and vibrating tube banks and published laboratory experimental data. The criteria can be used for the prediction of Acoustic Vibration in steam generator and heat exchanger tube banks both, in-line and staggered.
EXPERIENCE WITH UNUSUAL Acoustic Vibration IN HEAT EXCHANGER AND STEAM GENERATOR TUBE BANKSJournal of Fluids and Structures, 1996Co-Authors: F. L. Eisinger, Robert E. SullivanAbstract:
Cases of atypical Acoustic Vibration in heat exchanger and steam generator tube banks are presented. The cases include a tubular air heater with Acoustic Vibration developed in the flow direction, a steam generator tube bank with Vibration developed along the tubes, and a shell and tube process heat exchanger with Acoustic Vibration developed in the shell axial direction. The vibratory cases were compared with a number of steam generator tube banks in service which did not develop Acoustic Vibration. The Vibration prediction methodology developed recently for heat exchangers vibrating in the transverse Acoustic modes was applied to the cases studied. It is shown that this methodology is also applicable to the prediction of the unusual Acoustic Vibration described in this paper.
Shang-zhong Jin – One of the best experts on this subject based on the ideXlab platform.
Acoustic Vibration sensor based on nonadiabatic tapered fibers.Optics letters, 2012Co-Authors: Ben Xu, Yi Li, Miao Sun, Zhen-wei Zhang, Xin-yong Dong, Zai-xuan Zhang, Shang-zhong JinAbstract:
A simple and low-cost Vibration sensor based on single-mode nonadiabatic fiber tapers is proposed and demonstrated. The environmental Vibrations can be detected by demodulating the transmission loss of the nonadiabatic fiber taper. Theoretical simulations show that the transmission loss is related to the microbending of the fiber taper induced by Vibrations. Unlike interferometric sensors, this Vibration sensor does not need any feedback loop to control the quadrature point to obtain a stable performance. In addition, it has no requirement for the coherence of the light source and is insensitive to temperature changes. Experimental results show that this sensing system has a wide frequency response range from a few hertz to tens of kilohertz with the maximal signal to noise ratio up to 73 dB.