PSI - Issue 60

Available online at www.sciencedirect.com

Science Direct

Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2023) 000–000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 60 (2024) 364–371

Third International Conference on Structural Integrity 2023 (ICONS 2023)

Exploring Modal Analysis Technique for Identifying Proper Assembly of ECFM in Vertical Centrifugal Pumps of Fast Reactor Ashish Kumar a *, Y.V.Nagaraja Bhat a , Sudheer Patri a , P.Anup Kumar a , S.I.Sundar Raj a , S.Sureshkumar a , B.K.Sreedhar a

a Indira Gandhi Centre for Atomic Research, Kalpakkam, T.N. 603102, India

Abstract

© 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the ICONS 2023 Organizers Vertical centrifugal pumps are provided in fast reactors for circulating the primary coolant and flow measurements in these pumps are done using Eddy Current Flow Meters (ECFM). ECFM is an assembly of Outer and Inner Guide Tube (IGT) and a probe that needs replacement after every five years of operation. IGT is a nine meter long, slender component that requires blind insertion through intermittent supports in the pump’s stationary portion. IGT, being flexible, may miss out on its supports during assembly, leading to errors in flow measurement, undesired flow-induced vibration, and stresses. In-situ vibration measurements were conducted to ensure proper assembly of the IGT. The experimental results were then compared with analytical ones obtained using finite element based models to confirm the number of supports acting on IGT. This paper describes the experiments and related analyses, with the help of which vibration characteristics of ECFM assembly are understood and a conclusion on the state of IGT supports is reached. © 2024 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0)

Peer-review under responsibility of the ICONS 2023 Organizers Keywords: Modal Analysis, Fast Reactor Pumps, Eddy Current Flow Meter

1. Introduction

Vertical centrifugal Liquid Metal Pumps (LMP) are employed for primary coolant flow in Fast Breeder Reactors (FBR), and flow measurements in these pumps are done using Eddy Current Flow Meters (ECFM), Poornapushpakala et al. (2014). ECFM is an assembly of an Outer Guide Tube (OGT), an Inner Guide Tube (IGT), and a probe. While the OGT is permanently fixed in the shielding box of the pump, the IGT, which is 9.5 m long, is

* Corresponding author. Tel.: +91-044-27480500 (ext. 20126). E-mail address: ashishkumar@igcar.gov.in

2452-3216© 2024 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the ICONS 2023 Organizers

2452-3216 © 2024 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the ICONS 2023 Organizers 10.1016/j.prostr.2024.05.057