0
Research Papers

Level Dynamics Monitoring of a Once-Through Steam Generator: A New Method Using the Reflectometric Technique

[+] Author and Article Information
Francesco Cordella

ENEA FSN-FUSPHY-SAD—Frascati Research Center, Via E. Fermi, 45, Frascati 00044, Italy e-mail: francesco.cordella@enea.it

Mauro Cappelli

ENEA FSN-FUSPHY-SCM—Frascati Research Center, Via E. Fermi, 45, Frascati 00044, Italy e-mail: mauro.cappelli@enea.it

Massimo Sepielli

ENEA FSN—Casaccia Research Center, Via Anguillarese, 301, Rome 00123, Italy e-mail: massimo.sepielli@enea.it

Manuscript received August 27, 2015; final manuscript received May 19, 2016; published online October 12, 2016. Assoc. Editor: Jovica R. Riznic.

ASME J of Nuclear Rad Sci 2(4), 041003 (Oct 12, 2016) (10 pages) Paper No: NERS-15-1181; doi: 10.1115/1.4033696 History: Received August 27, 2015; Accepted May 19, 2016

We present here some theoretical and experimental results about the application of the time-domain reflectometry (TDR) technique to a once-through steam generator (OTSG) bayonet-type, which is considered here, from a new point of view, as a coaxial transmission line and used as a level monitoring device for its own dynamics. This original approach leads to the design of a new kind of sensor, employable as a general-level measuring system in harsh conditions as well. This sensor may offer some interesting features for the design of control systems for nuclear facilities as well as for oil and gas plants. In order to experimentally verify the theoretical part, a mockup has been designed and built, so as to be used as a level control for a dedicated hydraulic loop system both in static and dynamic conditions. The purpose of the hydraulic loop system is to implement a short-/medium-term transient-level dynamics requiring fast sensor response, online measurement, and some nonlinearity features that are crucial for its control. The obtained results show that the TDR application on the OTSG is feasible at standard ambient temperature and pressure (SATP) conditions, paving the way for tests at the operating pressure and temperature ranges of a real plant.

FIGURES IN THIS ARTICLE
<>
Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Pictorial view of the heat-transfer regions in a general OTSG

Grahic Jump Location
Fig. 2

Simulation results for different physical parameters: (a) pressure, (b) L1 level, and (c) L2 level response to a step of flow rate and thermal flux

Grahic Jump Location
Fig. 3

Schematic view of the experimental configuration for “static” level measurements

Grahic Jump Location
Fig. 4

Level sensor geometries, details, and simplified model

Grahic Jump Location
Fig. 5

Hydraulic loop for “dynamic” level measures

Grahic Jump Location
Fig. 6

Experimental data and fitting curve of the step function response

Grahic Jump Location
Fig. 7

Different “static” level measurements (from right to left: baseline in air, 10.5×10−2  m, 20.5×10−2  m, 40×10−2  m of water at 293.15 K)

Grahic Jump Location
Fig. 9

Level-detection algorithm block diagram

Grahic Jump Location
Fig. 10

rs–bs (dashed black line), rs–bs piecewise linear approx. (thick dashed line), rs–bs first derivative (dashed-dotted thin line)

Grahic Jump Location
Fig. 11

Zoom of the level-point determination algorithm with the complete rs–bs curve (inset)

Grahic Jump Location
Fig. 12

Data streaming viewed with ML

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In