ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
Sep 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
Fusion Science and Technology
October 2025
Latest News
Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
Alexandre Vagtinski de Paula, Luiz Augusto Magalhães Endres, Sergio Viçosa Möller
Nuclear Science and Engineering | Volume 184 | Number 3 | November 2016 | Pages 334-345
Technical Paper | doi.org/10.13182/NSE16-30
Articles are hosted by Taylor and Francis Online.
This paper presents a study of the identification of flow patterns inside a tube bank with the technique of symbolic dynamics. The experimental signals of the mean velocity and its fluctuations are measured by hot-wire anemometry in an aerodynamic channel and used as input data for the symbolic dynamics technique. The tube bank consists of 23 circular cylinders in a triangular arrangement. The pitch-to-diameter ratio chosen was 1.26 and the Reynolds numbers are in the range from 7.5 × 103 to 4.4 × 104, computed with the tube diameter, D = 25.1 mm, and the percolation velocity. In this work, a binary alphabet was chosen to convert and analyze the data. The partitioning process is performed through the mean value of the time series and via discrete wavelet reconstruction, according to a chosen reconstruction level. The flow patterns are presented for different positions inside the tube bank, where histograms and probability density functions support the statistical interpretation. The histograms with a decimal representation for the original experimental time series with partitioning performed through the mean value show that the signals do not present fast changes of velocity fluctuations. This behavior was observed in the five rows of cylinders. However, by changing the partitioning according to a wavelet reconstruction of the signal with high frequency, which means that the signals are close to the partitioning function, fast changes appear in all of the time series observed. The results indicate that the turbulence in tube banks has chaotic characteristics. Flow visualizations performed with ink injection inside the tube bank helped in the interpretation of the results.
