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Basic Thermal-Hydraulics Experiments for Nuclear Engineering Students

Teaching Assistantship Final Report

Syeilendra Pramuditya

Department of Nuclear EngineeringTokyo Institute of Technology

March 12, 2013

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Introduction

This educational program is intended for new comers in nuclear engineering department

Introduce thermal-hydraulic experimental researchIntroduce basic experimental techniquesIntroduce the methods of data acquisition, extraction, and processing

Experimental activitiesSpot welding & Silver brazingCavitationSingle-phase heat transferTwo-phase boiling regimes[New for FY 2013] Condensation apparatus[New for FY 2013] Pool boiling critical heat flux (CHF) apparatus

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Spot Welding & Silver BrazingSpot welding is one of the most basic experimental techniques. The purpose is to attach thermocouple onto heater pin surface so that temperature measurement can be performed.

Spot Welding Safety goggles

Electricspark

Air fanHelmet withface protector

Leathergloves

Fire-proofsheet

Silver BrazingSilver brazing is part of heater pin construction technique. The purpose is to connect/combine SUS304 pin and copper electrodes.As a TA:

Make sure that the equipments, tools, and materials are all readyMake the students understand about the purpose of the activityTeach students about best practices related to the safety of the activity

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CavitationExplain to students: Cavitation is one of the key issues in the LMFR development & design since it can cause component damages. And therefore cavitation must be avoided in reactor operation.Occurrence of cavitation can be identified using the concept of cavitation coefficientTeach the technique to get cavitation coefficient experimentally.

60

Φ6.

5

Φ27

.2

Φ21

20

Φ21

3010

( ) 212

020

212

0

V

PP

VV

PPK

ρυ

ρυ −

≈

−

−=

y = 1040.9x - 6.1218

R 2 = 0.9783

0

200

400

600

800

1000

1200

0% 20% 40% 60% 80% 100% 120%

pressure difference

(L/min)2

差圧伝送器出力電圧（%）

(流量

)2(L

/min

)2

y = 0.0036x + 0.0998R2 = 0.9992

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 2 4 6 8 10 12 14 16 18

mV

MPa

abs

olut

e

圧力変換器出力電圧（mV）

静圧

(Mpa

-a)

Cavitation test section

Pressure calibration curve Mass flow rate calibration curve

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Single-Phase Heat TransferExplain to students: The study of heat transfer is an important part in nuclear engineering research, since the transport of energy from fuel pin to the coolant is governed by heat transfer mechanism.The purpose of the activity is to teach students of obtaining Nusselt number experimentally.

Assembling the test section

Heater pin

Pressuregauge

Safety valve

Thermocouples

D=13.0mm (O.D.15mm)

d=4.57mm (t 0.28mm)

入口(温度Tin）

L=40

0mm

ヒーターピン（直接通電）

石英 ガラス管

銅製電極

出口

銅製電極

シャント抵抗（電流測定用）

熱電対(表面温度Tw）

V

V

バルク温度Tb

L 1

直流安定化電源（DC 0-10Vにて遠隔操作）

/e

w b

Nu hD kqh

T T

≡

=−

P P

P

空気冷却塔

バッファタンク

凝縮器

試験部

オリフィス流量計

予熱器

P：ポンプ

冷却器

Test section schematic

Water loop schematic

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Double Monitoring StationsDouble monitoring stations have been arrangedSingle-phase heat transfer and cavitation experiments could be performed simultaneouslyStudents could have more time to perform the experiments and data acquisitions smoothly

First monitoring station

MS1

Large d

esk

MS2

Second monitoring station

Projector

Observationmonitor

Control panel

Water loop

Door

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Two-Phase Boiling Flow RegimesExplain to students: Two-phase boiling flow is an important aspect in nuclear reactor operation. The phenomenon occurs in steam generator and BWR core.Teach the students about experimental observation of various two-phase boiling regimes.

Operation of high speed video camera

蒸気流 (Steam flow)

噴霧流 (Mist flow)

環状噴霧流 (Annular mist flow)

チャーン流・フロス流 (Churn flow, Froth flow)スラグ流 (Slug flow)

気泡流 (Bubbly flow)

表面沸騰流 (Surface boiling flow)液体流 (Liquid flow)

PWR

BWR

Test section

Thermocouples

Protectivetransparent sheet

High speed camera

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Condensation Apparatus [New for FY2013]Main purpose: give real insights to students, through experiment, about isolation condenser (IC) system typically installed in BWR (such as in Fukushima).

Study of loop-pool heat transfer with phase change.Techniques to estimate overall heat transfer coefficient, latentheat, heat capacity, etc.

Pool

Loop

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Pool boiling CHF apparatus [New for FY2013]Main purpose: give real insights to students, through experiment, about the basics of critical heat flux (CHF).

Experimental measurement technique: Dependency of electrical resistance on temperature (Kanthal vs Platinum).Critical heat flux estimation technique.

CADAC data logger and PC to monitor temperatures (via voltage and/or current)

Simulated pinCoolant

Cu electrodes

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Working Language for the Activities

The activities were mainly conducted in English (with the support of the supervising teacher).

Most participants could understand and communicate well.Nevertheless, some (few) had problem to understand and communicate -> can be considered a good point for education.

The manual book for the activities has been partially translated from Japanese into English (to accommodate international students in the future).

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Translation Work

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Translation Work

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Translation Work

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Concluding Remarks

~ Thank you very much for your attention ~

As a TA: help the students to understand each of the experiment, good preparation, emphasize the importance of safety, support them during the activity (smooth & effective experiment)Students understood the importance of safety, best practices, and standard procedures when doing experimental worksGood results could be obtained according to the students’ reportsA number of improvements have been made to this educational program (double monitoring stations, the use of handy talky, megaphone, replacement of orifice, signal noise reduction, improved spot welding technique, etc)The manual book for the activities has been partially translated from Japanese into EnglishTwo new apparatuses which can be used in FY 2013 has been constructed and partially tested.The activities are very useful to provide experimental knowledge, skills and real insights, for those whose main work/research is not directly related to experiment (like myself).