Simulation of Tube-to-Support Dynamic Interaction in Heat Exchange Equipment

1989 ◽  
Vol 111 (4) ◽  
pp. 378-384 ◽  
Author(s):  
N. J. Fisher ◽  
M. J. Olesen ◽  
R. J. Rogers ◽  
P. L. Ko
Keyword(s):  
Heat Exchange ◽  
Heat Exchangers ◽  
Room Temperature ◽  
Analytical Techniques ◽  
Dynamic Interaction ◽  
Fretting Wear ◽  
Flow Induced Vibration ◽  
Support Plate ◽  
Heat Exchange Equipment ◽  
Good Agreement

Tubes within tube and shell heat exchange components are supported at intermediate points by support plates. Flow-induced vibration of a tube can cause it to impact or rub against a support plate or against adjacent tubes and can result in tube fretting-wear. The tube-to-support dynamic interaction is used to relate experimental wear data from test rigs to real multi-span heat exchanger configurations. Analytical techniques are required to estimate this interaction in real heat exchangers. Simulation results from the VIBIC code are in good agreement with three examples from the open literature and are in reasonable agreement with measurements from the CRNL single-span room temperature fretting-wear rigs. Therefore, the VIBIC code is a good analytical tool for estimating tube-to-support dynamic interaction in real heat exchangers.

scholarly journals POLYMERS AND PLASTIC USE FOR THE HEAT-EXCHANGE EQUIPMENT (REVIEW)

2020 ◽  
pp. 59-71
Author(s):  
I.O. Mikulionok
Keyword(s):  
Heat Exchange ◽  
Heat Exchangers ◽  
Polymeric Materials ◽  
Strength Properties ◽  
Polymers And Plastics ◽  
Heat Exchange Equipment ◽  
Coefficient Of Heat Conductivity ◽  
Exchange Apparatus ◽  
Polymer Type

The possibility of use of the heat-exchangers in whole or in part manufactured with use of polymers and plastics is considered. Despite obvious, at first sight, inexpediency of use of polymeric materials in the heat-exchange equipment (low coefficient of heat conductivity, and also low, in comparison with metals, the strength properties of the majority of the most widespread polymers), «polymeric» heat-exchangers find application in various areas of the industry more and more surely. Classification of heat-exchange apparatuses which constructive elements are executed with use of polymeric materials is proposed. The following signs are the basis for classification: polymer type, a type of polymer meric material, type of the heat-exchange apparatus (a form of heat-exchange elements), reliance on polymeric materials in apparatuses, motion freedom of polymeric heat-exchange elements, level of assembly of a design, and also diameter of tubular elements. Critical analysis the most characteristic designs developed by domestic and foreign designers and inventors is carried out. Ref. 21, Fig. 13.

Pressure Coefficient Distribution Over Tube Surfaces of Tube Bundle Subjected in Two-Phase Flow

2011 ◽  
Author(s):  
W. G. Sim
Keyword(s):  
Heat Exchangers ◽  
Two Phase Flow ◽  
Pressure Coefficient ◽  
Nuclear Industry ◽  
Fretting Wear ◽  
Phase Flow ◽  
Flow Induced Vibration ◽  
Two Phase ◽  
Coefficient Distribution ◽  
Vibration Excitation

Two-phase cross flow exists in many shell- and tube heat exchangers such as condensers, evaporators and nuclear steam generators. During the last two decades, research devoted to two-phase flow induced vibrations has increased, mainly driven by the nuclear industry. Flow-induced vibration excitation forces can cause excessive vibration which will result in long-term fretting-wear or fatigue. To avoid potential tube failures in heat exchangers, it is required for designer to have guidelines that incorporate flow-induced vibration excitation forces. The phenomenon of the vibration of tubes in two-phase flow is very complex and depends on factors which are nonexistent in single-phase flows. To understand the fluid dynamic forces acting on a structure subjected to two-phase flow, it is essential to get detailed information about the characteristics of two-phase flow. Pressure distributions generated by two-phase flow over tube surfaces yield more general information than the local velocity distribution. The pressure coefficient distribution obtained by experimental test has been evaluated.

Experimental Fretting-Wear Studies of Steam Generator Materials

1995 ◽  
Vol 117 (4) ◽  
pp. 312-320 ◽  
Author(s):  
N. J. Fisher ◽  
A. B. Chow ◽  
M. K. Weckwerth
Keyword(s):  
Steam Generator ◽  
Contact Force ◽  
Environmental Conditions ◽  
Analytical Techniques ◽  
Work Rate ◽  
Fretting Wear ◽  
Flow Induced Vibration ◽  
Dynamic Interactions ◽  
Support Materials ◽  
Wear Damage

Flow-induced vibration of steam generator tubes results in fretting-wear damage due to impacting and rubbing of the tubes against their supports. This damage can be predicted by computing tube response to flow-induced excitation forces using analytical techniques, and then relating this response to resultant wear damage using experimentally derived wear coefficients. Fretting-wear of steam generator materials has been studied experimentally at Chalk River Laboratories for two decades. Tests are conducted in machines that simulate steam generator environmental conditions and tube-to-support dynamic interactions. Different tube and support materials, tube-to-support clearances, and tube support geometries have been studied. The effect of environmental conditions, such as temperature, oxygen content, pH and chemistry control additive, have been investigated as well. Early studies showed that damage was related to contact force as long as other parameters, such as geometry and motion, were held constant. Later studies have shown that damage is related to a parameter called work-rate, which combines both contact force and sliding distance. Results of short and long-term fretting-wear tests for CANDU steam generator materials at realistic environmental conditions are presented. These results demonstrate that work-rate is an appropriate correlating parameter for impact-sliding interaction.

Fretting Wear of Heat Exchanger Tubes—Part I: Experiments

1979 ◽  
Vol 101 (4) ◽  
pp. 625-629 ◽  
Author(s):  
R. D. Blevins
Keyword(s):  
Heat Exchanger ◽  
Empirical Model ◽  
Room Temperature ◽  
Fretting Wear ◽  
Support Plate ◽  
Air Atmosphere ◽  
The Mean

The results of a series of measurements made on the fretting wear of heat exchanger tubes and support plates at room temperature in a nitrogen/air atmosphere are presented. The fretting wear is shown to be a function of the amplitude and frequency of tube vibration as well as the gap between the tube and the support plate and the mean load supported by the tube. An empirical model is developed in Part II for predicting the fretting wear.

scholarly journals Computational parametric study on efficiency of low boiling point fluid plants under heat exchange process intensification

2021 ◽  
Vol 289 ◽  
pp. 06003
Author(s):  
Alena Likhaeva ◽  
Sergey Grigoriev ◽  
Evgeniy Trushin ◽  
Marat Dasaev
Keyword(s):  
Heat Exchange ◽  
Parametric Study ◽  
Boiling Point ◽  
Heat Exchangers ◽  
Exchange Process ◽  
Electricity Consumption ◽  
Process Intensification ◽  
Exchange Processes ◽  
Heat Exchange Equipment ◽  
Heat Exchange Process

One of the main challenges for the energy industry is to improve the reliability and efficiency of heat exchange equipment in heating plants. Phase-change heat exchangers with low boiling point fluid (LBPF) are widely used in both conventional and renewable energy. The main objectives of increasing the efficiency of heat exchange equipment are to reduce the weight and dimensions, to increase the amount of heat transferred and to reduce the electricity consumption spent on pumping the heat transfer agent. These objectives are achieved by implementing various methods of heat exchange intensification in heat exchange equipment. A key aspect concerning application of various types of heat exchange intensifiers in heat exchange equipment is evaluation of possibility to increase their design efficiency. The paper presents the results of a computational parametric study of changes in efficiency of some LBPF-based plants when intensifying heat exchange processes by modifying functional surfaces of heat exchangers by laser ablation.

scholarly journals Research possibility of application of non-destructive testing method based on the Barkhausen effect for the control of heat exchange equipment, exposed to im-pulse pressure

2019 ◽  
Vol 114 ◽  
pp. 06011
Author(s):  
V.V. Potapov ◽  
M.V. Lopatin ◽  
L.I. Lopatina ◽  
L.M. Chebotnyagin
Keyword(s):  
Heat Exchange ◽  
Heat Exchangers ◽  
Control Method ◽  
Non Destructive Testing ◽  
Barkhausen Effect ◽  
Destructive Testing ◽  
Testing Method ◽  
Heat Exchange Equipment ◽  
Reliability Of Operation ◽  
Non Destructive

The article deals with the issues of ensuring the reliability of operation and methods for evaluation of connections (tube attachment points in tube sheets) of heat exchangers used in various industries. It is estimated the applicability of the control method based on the Barkhausen effect to check the place of tube fastening in tube sheets. Installations are considered as heat exchangers in which the connection is derive pipe with tube sheets is obtained by using impulsed pressure sources.

Vibration Analysis of Steam Generators and Heat Exchangers: An Overview — Part II: Vibration, Response, Fretting-Wear, Guidelines

2002 ◽  
Author(s):  
Michel J. Pettigrew ◽  
Colette E. Taylor
Keyword(s):  
Heat Exchangers ◽  
Vibration Analysis ◽  
Response Prediction ◽  
Design Guidelines ◽  
Vibration Response ◽  
Fretting Wear ◽  
Steam Generators ◽  
Flow Induced Vibration ◽  
Two Phase ◽  
Service Water

Design guidelines were developed to prevent tube failures due to excessive flow-induced vibration in shell-and-tube heat exchangers. An overview of vibration analysis procedures and recommended design guidelines is presented in this paper. This paper pertains to liquid, gas and two-phase heat exchangers such as nuclear steam generators, reboilers, coolers, service water heat exchangers, condensers, and moisture-separator-reheaters. Part 2 of this paper covers forced vibration excitation mechanisms, vibration response prediction, resulting damage assessment, and acceptance criteria.

Design Specifications to Ensure Flow-Induced Vibration and Fretting-Wear Performance in CANDU™ Steam Generators and Heat Exchangers

2009 ◽  
Author(s):  
Victor Janzen ◽  
Yingke Han ◽  
Michel Pettigrew
Keyword(s):  
Heat Exchangers ◽  
Dynamic Properties ◽  
Fretting Wear ◽  
Performance Criteria ◽  
Steam Generators ◽  
Flow Induced Vibration ◽  
Two Phase ◽  
Design Specifications ◽  
Field Evidence ◽  
Main Steam

Preventing flow-induced vibration and fretting-wear problems in steam generators and heat exchangers requires design specifications that bring together specific guidelines, analysis methods, requirements and appropriate performance criteria. This paper outlines the steps required to generate and support such design specifications for CANDU™ nuclear steam generators and heat exchangers, and relates them to typical steam-generator design features and computer modeling capabilities. It also describes current issues that are driving changes to flow-induced vibration and fretting-wear specifications that can be applied to the design process for component refurbishment, replacement or new designs. These issues include recent experimental or field evidence for new excitation mechanisms, e.g., the possibility of in-plane fluidelastic instability of U-tubes, the demand for longer reactor and component lifetimes, the need for better predictions of dynamic properties and vibration response, e.g., two-phase random-turbulence excitation, and requirements to consider system “excursions” or abnormal scenarios, e.g., a main steam line break in the case of steam generators. The paper describes steps being taken to resolve these issues.

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