Abstract

The reliability of the heat exchanger tube bundle not only affects the economic efficiency of production but also relates to the normal development of production safety and health. To study the flow-induced vibration of tube bundles, a three-dimensional finite element model of heat exchange tubes and watersheds inside and outside the tubes was established to explore the flow-induced vibration characteristics of tube bundles and analyze the natural frequencies of single-span and multispan heat exchange tubes. Considering the randomness of the effective support between the tube bundle and the support plate of the heat exchanger, the natural frequency and vibration mode of the four-span tube with failure of the tube bundle support are analyzed. On this basis, the vibration caused by the two-way coupling flow between tube and tube outflow is calculated. Finally, the flow-induced vibration characteristics of the five-tube bundle with two different pitch-diameter ratios are analyzed. The calculation results show that the error between the calculated natural frequencies and the theoretical values is less than 3%, and within the allowable error range, the natural frequencies of the same order decrease with the increase of the number of support failures. The vibration frequencies of single-span and multispan tube bundles are consistent with the lift and drag frequencies, the vibration displacement curves show typical Strouhal modes, and the amplitude increases with the increase of fluid velocity. Vibration displacement curves of symmetrical spans of multispan tube bundles are similar in shape and amplitude. With the increase of tube bundle spacing, the vibration characteristics become more obvious.

Highlights

  • With the development of energy-saving technology, the heat exchanger has been widely used in the chemical industry and has brought significant economic benefits

  • E calculation results show that the errors between the theoretical value of the natural frequency of single-span tube and the natural frequency calculated by numerical simulation gradually increase with the increase of order, and the maximum error of the first five order frequencies is about 1.34%, which is within the allowable range. e calculation results are effective, and the calculation of the natural frequency for single-span tube by numerical simulation will not cause great errors

  • The heat exchanger tube bundle is taken as the research object

Read more

Summary

Introduction

With the development of energy-saving technology, the heat exchanger has been widely used in the chemical industry and has brought significant economic benefits. According to the analysis of fluid elastic instability, Liu and others put forward a new instability model based on other people’s research and pointed out that the improved model has the advantages of better calculation accuracy and less dependence on experimental data [22], but it does not analyze the flow-induced vibration of elastic tube bundle caused by vortex shedding, which has certain limitations. E two-way fluid-structure coupling method is used to analyze the flow-induced vibration of a single tube bundle with elastic support and to calculate the vortex-induced vibration of fivetube bundles with two different spacing As a consequence, it provides a reference for studying the flow-induced vibration of multiple tube bundles by using the two-way fluidstructure coupling method

Natural Frequency of Heat Exchange Tube
Flow-Induced Vibration of Heat Exchange Tubes
Span II span III span IV span
Findings
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call