Juhani Hyvärinen

Advancing the Understanding of Non-Condesable Gases in Reactor Coolant System: NCGDENSE Program

2025

Publication type

A4 Conference proceedings

Author(s)

Singh Sharandeet, Patel Giteshkumar, Pyy Lauri, Hyvärinen Juhani

Other focus area

LUT School of Energy Systems

Computational Fluid Dynamics Analysis of the Core of the MOTEL Facility

2025

Publication type

A4 Conference proceedings

Author(s)

Patel Giteshkumar, Rahim Ananya Nazia, Telkkä Joonas, Hyvärinen Juhani

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Experimental studies on nitrogen’s effect on reactor core cooling during a hot leg SBLOCA in a scaled EPR model

2025

Publication type

A1 Journal article (refereed), original research

Author(s)

Riikonen Vesa, Kouhia Virpi, Puustinen Markku, Patel Giteshkumar, Räsänen Antti, Kotro Eetu, Hyvärinen Juhani

Energy transition

LUT School of Energy Systems

Flow oscillation fade-out and pool water level effect experiments on open loop passive cooling system

2025

Publication type

A1 Journal article (refereed), original research

Author(s)

Telkkä Joonas, Riikonen Vesa, Räsänen Antti, Kotro Eetu, Hyvärinen Juhani

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Multiphysics Coupled Calculations Using OpenFOAM, Serpent, and External Heat Conduction Solver for Prismatic GCRs: A Case Study on HTTR

2025

Publication type

A4 Conference proceedings

Author(s)

Abulawi Zaid, Rintala Ville, Suikkanen Heikki, Tiselj Iztok, Hyvärinen Juhani, Liu Yang

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

NCGDENSE Program: Advancing the Understanding of Non-Condensable Gases in Nuclear Reactor Coolant Systems

2025

Publication type

A4 Conference proceedings

Author(s)

Singh Sharandeet, Patel Giteshkumar, Pyy Lauri, Hyvärinen Juhani

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Numerical Modelling of Two-Phase Critical Flow in a Steam Generator Guillotine Tube Rupture Scenario

2025

Publication type

A4 Conference proceedings

Author(s)

Patel Giteshkumar, Pyy Lauri, Singh Sharandeet, Zaitsev Andrei, Hyvärinen Juhani

Energy transition

LUT School of Energy Systems

Techno-economic analysis of alternative energy sources for icebreakers in the Baltic Sea

2025

Publication type

A1 Journal article (refereed), original research

Author(s)

Lehmusto Mika, Khalid Umair, Cobben Max, Bolbot Victor, Elg Mia, Hyvärinen Juhani, Santasalo-Aarnio Annukka, Banda Valdez Osiris

Planetary resources

Energy transition

Energy Engineering and Power Technology

Nuclear Energy and Engineering

Renewable Energy, Sustainability and the Environment

LUT School of Energy Systems

Two-phase Critical Flow Experiments at LUT University

2025

Publication type

A4 Conference proceedings

Author(s)

Pyy Lauri, Hyvärinen Juhani, Puustinen Markku, Patel Giteshkumar

Energy transition

Energy Engineering and Power Technology

Nuclear Energy and Engineering

Energy

LUT School of Energy Systems

Utilizing Thermal Inertia of Bedrock as a Passive Heat Sink for Small Modular Reactors

2025

Publication type

A4 Conference proceedings

Author(s)

Pomogaev Aleksandr, Hyvärinen Juhani, Patel Giteshkumar, Vihavainen Juhani

Other focus area

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Contribution of transient heat transfer to overpressure protection in a passive Boiling Water Reactor

2024

Publication type

A1 Journal article (refereed), original research

Author(s)

Pomogaev Aleksandr, Hyvärinen Juhani, Vihavainen Juhani

Energy transition

LUT School of Energy Systems

Creating the foundations for safe nuclear power in Finland – Thermal hydraulics, safety analyses, safety justification methods research at the LUT University, 2000–2023

2024

Publication type

A1 Journal article (refereed), original research

Author(s)

Hyvärinen Juhani, Riikonen Vesa, Telkkä Joonas, Hujala Elina, Kouhia Virpi, Puustinen Markku, Patel Giteshkumar, Pyy Lauri, Vihavainen Juhani, Suikkanen Heikki, Rintala Ville

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Development and Validation of Pattern Recognition Algorithm and Suppression Pool Flow Modeling

2024

Publication type

A1 Journal article (refereed), original research

Author(s)

Patel Giteshkumar, Hujala Elina, Tanskanen Vesa, Puustinen Markku, Hyvärinen Juhani

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Experiments on open loop passive cooling of nuclear reactor containment: Quasi-steady-state heat removal, dynamic loads, and feasibility of practical periodic testing

2024

Publication type

A1 Journal article (refereed), original research

Author(s)

Telkkä Joonas, Riikonen Vesa, Kouhia Virpi, Puustinen Markku, Pyy Lauri, Räsänen Antti, Kotro Eetu, Hyvärinen Juhani

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Helical coil steam generator stability experiments with the MOTEL test facility

2024

Publication type

A1 Journal article (refereed), original research

Author(s)

Riikonen Vesa, Telkkä Joonas, Kouhia Virpi, Puustinen Markku, Patel Giteshkumar, Pyy Lauri, Räsänen Antti, Kotro Eetu, Hyvärinen Juhani, Murad Afeef

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Nuclear engineering and design nuclear heat supply system for a small district heating reactor

2024

Publication type

A1 Journal article (refereed), original research

Author(s)

Teräsvirta Antti, Hyvärinen Juhani

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

The SARENA Programme: Master's degree studies in nuclear engineering combining different educational and cultural environments

2024

Publication type

A1 Journal article (refereed), original research

Author(s)

Kljenak Ivo, Abdelouas Abdesselam, Desmytter Manon, Elorza Francisco J., Gallego Eduardo, Hartnack Andreas, Hartnack Christoph, Hyvärinen Juhani, Vihavainen Juhani, Tiselj Iztok

Energy transition

LUT School of Energy Systems

Development and Validation of Pattern Recognition Algorithm and Suppression Pool Flow Modelling

2023

Publication type

A4 Conference proceedings

Author(s)

Patel Giteshkumar, Puustinen Markku, Hyvärinen Juhani, Hujala Elina, Tanskanen Vesa

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Efficiency of Passive Open Loop Heat Removal over Wide Range of Loop Flow Resistances -- PASI Loop Tests in the EU-PASTELS Project

2023

Publication type

A4 Conference proceedings

Author(s)

Telkkä Joonas, Riikonen Vesa, Räsänen Antti, Kotro Eetu, Hyvärinen Juhani

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Helical Coil Steam Generator Experiments with the MOTEL SMR Test Facility in the EU-McSAFER Project

2023

Publication type

A4 Conference proceedings

Author(s)

Telkkä Joonas, Suikkanen Heikki, Räsänen Antti, Kotro Eetu, Hyvärinen Juhani

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

Modeling of horizontal steam injection in a water pool

2023

Publication type

A1 Journal article (refereed), original research

Author(s)

Patel Giteshkumar, Hujala Elina, Puustinen Markku, Hyvärinen Juhani

Energy transition

LUT School of Energy Systems

Optimization of Natural Circulation District Heating Reactor Primary Heat Exchangers

2023

Publication type

A1 Journal article (refereed), original research

Author(s)

Saari Jussi, Suikkanen Heikki, Mendoza-Martinez Clara, Hyvärinen Juhani

Energy transition

Energy Engineering and Power Technology

Nuclear Energy and Engineering

Energy

Engineering

LUT School of Energy Systems

An overall safety concept for nuclear power plants

2022

Publication type

A1 Journal article (refereed), original research

Author(s)

Hyvärinen Juhani, Vihavainen Juhani, Ylönen Marja, Valkonen Janne

Energy transition

LUT School of Energy Systems

Modeling of Horizontal Steam Injection in a Water Pool

2022

Publication type

A4 Conference proceedings

Author(s)

Patel Giteshkumar, Hujala Elina, Puustinen Markku, Hyvärinen Juhani

Energy transition

LUT School of Energy Systems

MOTEL-SMR integral PWR system test facility - design and first test results

2022

Publication type

A4 Conference proceedings

Author(s)

Hyvärinen Juhani, Telkkä Joonas, Tielinen Kimmo

Energy transition

Nuclear Energy and Engineering

LUT School of Energy Systems

PIEMOS-selvitys: Uusien ydinenergiateknologioiden mahdollisuudet ja kehitystarpeet

2022

Publication type

D1 Article in a trade journal

Author(s)

Hyvärinen Juhani, Vihavainen Juhani

Energy transition

LUT School of Energy Systems

Uusien ydinenergiateknologioiden mahdollisuudet ja kehitystarpeet : Pienet modulaariset sarjavalmisteiset ydinreaktorit eli SMR:t

2022

Publication type

D4 Published development or research report or study

Author(s)

Hujala Elina, Hyvärinen Juhani, Rintamaa Rauno, Suikkanen Heikki, Vihavainen Juhani, Wähä Susanna

Energy transition

LUT School of Energy Systems

PASI – A test facility for research on passive heat removal

2021

Publication type

A1 Journal article (refereed), original research

Author(s)

Kouhia Virpi, Riikonen Vesa, Kauppinen Otso-Pekka, Telkkä Joonas, Hyvärinen Juhani

Nuclear Energy and Engineering

LUT School of Energy Systems

PASI – A test facility for research on passive heat removal

2021

Publication type

A4 Conference proceedings

Author(s)

Kouhia Virpi, Riikonen Vesa, Kauppinen Otso-Pekka, Telkkä Joonas, Hyvärinen Juhani

Nuclear Energy and Engineering

LUT School of Energy Systems

Reactor core conceptual design for a scalable heating experimental reactor, LUTHER

2021

Publication type

A4 Conference proceedings

Author(s)

Truong Thinh, Suikkanen Heikki, Hyvärinen Juhani

Nuclear Energy and Engineering

LUT School of Energy Systems

The Sarena Project: Completing a Master's Degree in Nuclear Engineering Combining Different Educational and Cultural Environments

2021

Publication type

A4 Conference proceedings

Author(s)

Abdelouas A., Hartnack C., Gallego E., Elorza F.J., Hyvärinen J., Vihavainen J., Tiselj I., Kljenak I.

Energy transition

LUT School of Energy Systems

Defining void fraction with axial wire-mesh sensor in a swirling two-phase flow

2019

Publication type

A4 Conference proceedings

Author(s)

Telkkä Joonas, Jämsén Siiri, Hyvärinen Juhani

Nuclear Energy and Engineering

LUT School of Energy Systems

Image Analysis of Bubbling Mode Condensation Oscillations in Horizontal Sparger

2019

Publication type

A4 Conference proceedings

Author(s)

Hujala Elina, Tanskanen Vesa, Patel Giteshkumar, Hyvärinen Juhani

PASI - a test facility for research on passive heat removal

2019

Publication type

Other

Author(s)

Kouhia Virpi, Riikonen Vesa, Kauppinen Otso-Pekka, Telkkä Joonas, Hyvärinen Juhani

Nuclear Energy and Engineering

LUT School of Energy Systems

System code analysis of accumulator nitrogen discharge during LOCA experiment at PWR PACTEL test facility

2019

Publication type

A1 Journal article (refereed), original research

Author(s)

Kauppinen Otso-Pekka, Kouhia Virpi, Riikonen Vesa, Hyvärinen Juhani

Corrigendum to Direct contact condensation modeling in pressure suppression pool system [Nuclear Engineering and Design 321 (2017) 328–342](S0029549316302977)(10.1016/j.nucengdes.2016.08.026))

2018

Publication type

A1 Journal article (refereed), original research

Author(s)

Patel Giteshkumar, Tanskanen Vesa, Hujala Elina, Hyvärinen Juhani

Experimental observation of adverse and beneficial effects of nitrogen on reactor core cooling

2018

Publication type

A1 Journal article (refereed), original research

Author(s)

Riikonen Vesa, Kouhia Virpi, Kauppinen Otso-Pekka, Sjövall Heikki, Hyvärinen Juhani

Frequency analysis of chugging condensation in pressure suppression pool system with pattern recognition

2018

Publication type

A1 Journal article (refereed), original research

Author(s)

Hujala Elina, Tanskanen Vesa, Hyvärinen Juhani

Nuclear Energy and Engineering

LUT School of Energy Systems

Pattern recognition algorithm for analysis of chugging direct contact condensation

2018

Publication type

A1 Journal article (refereed), original research

Author(s)

Hujala Elina, Tanskanen Vesa, Hyvärinen Juhani

DEM in Analyses of Nuclear Pebble Bed Reactors

2017

Publication type

A4 Conference proceedings

Author(s)

Suikkanen Heikki, Rintala Ville, Hyvärinen Juhani

Nuclear Energy and Engineering

LUT School of Energy Systems

Direct contact condensation modeling in pressure suppression pool system

2017

Publication type

A1 Journal article (refereed), original research

Author(s)

Patel Giteshkumar, Tanskanen Vesa, Hujala Elina, Hyvärinen Juhani

Nuclear Energy and Engineering

Energy

Modelling and Simulation

LUT School of Energy Systems

Estimation of velocity fields from the axial wire-mesh sensor data

2017

Publication type

A1 Journal article (refereed), original research

Author(s)

Telkkä Joonas, Ylönen Arto, Hyvärinen Juhani, Varju Tamas

Nuclear Energy and Engineering

LUT School of Energy Systems

Frequency Analysis of Chugging Condensation in Pressure Suppression Pool System with Pattern Recognition

2017

Publication type

A4 Conference proceedings

Author(s)

Hujala Elina, Tanskanen Vesa, Hyvärinen Juhani

Modularity Based Requirements of MOTEL

2017

Publication type

D4 Published development or research report or study

Author(s)

Telkkä Joonas, Hyvärinen Juhani, Kauppinen Otso-Pekka

Numerical Modelling of Direct Contact Condensation of Steam in BWR Pressure Suppression Pool System

2016

Publication type

A4 Conference proceedings

Author(s)

Patel Giteshkumar, Tanskanen Vesa, Hyvärinen Juhani

Other focus area

LUT School of Energy Systems

Research based requirements of MOTEL

2016

Publication type

Other

Author(s)

Telkkä Joonas, Hyvärinen Juhani

Nuclear Energy and Engineering

Energy

LUT School of Energy Systems

ANALYSIS OF REVERSE FLOW IN LOW-RISE INVERTED U-TUBE STEAM GENERATOR OF PWR PACTEL FACILITY

2015

Publication type

A4 Conference proceedings

Author(s)

Kauppinen Otso-Pekka, Riikonen Vesa, Kouhia Virpi, Hyvärinen Juhani

Energy

Engineering

LUT School of Energy Systems

CFD modelling of chugging condensation regime of bwr suppression pool experiments

2015

Publication type

A4 Conference proceedings

Author(s)

Tanskanen Vesa, Patel Giteshkumar, Puustinen Markku, Hujala Elina, Kyrki-Rajamäki Riitta, Hyvärinen Juhani

Nuclear Energy and Engineering

Fluid Flow and Transfer Processes

Energy

LUT School of Energy Systems

Computer analyses on loop seal clearing experiment at PWR PACTEL

2015

Publication type

A1 Journal article (refereed), original research

Author(s)

Kauppinen Otso-Pekka, Kouhia Virpi, Riikonen Vesa, Hyvärinen Juhani, Sjövall Heikki

Nuclear Energy and Engineering

LUT School of Energy Systems

Sources and Effect of Non-Condensable Gases in Reactor Coolant System ofLWR

2015

Publication type

A4 Conference proceedings

Author(s)

Kral Pavel, Hyvärinen Juhani, Prosek Andrej, Guba Attila

Nuclear Energy and Engineering

Safety, Risk, Reliability and Quality

Energy

LUT School of Energy Systems

Study of Two-Phase Pipe Flow using the Axial Wire-Mesh Sensor

2015

Publication type

A4 Conference proceedings

Author(s)

Ylönen Arto, Hyvärinen Juhani

Experimental and Numerical Studies of Liquid Dispersal from a Soft Projectile Impacting a Wall

2007

Publication type

A4 Conference proceedings

Author(s)

Silde Ari, Hostikka Simo, Kankkunen Ari, Hyvärinen Juhani, Hakola Ilkka

Nuclear Energy and Engineering

Mechanics of Materials

Civil and Structural Engineering

LUT School of Energy Systems

Impact Test Facility

2007

Publication type

A4 Conference proceedings

Author(s)

Lastunen Auli, Hakola Ilkka, Järvinen Erkki, Calonius Kim, Hyvärinen Juhani

Nuclear Energy and Engineering

Safety, Risk, Reliability and Quality

Civil and Structural Engineering

LUT School of Energy Systems

Numerical Studies on Impact Loaded Reinforced Concrete Walls

2007

Publication type

A4 Conference proceedings

Author(s)

Saarenheimo Arja, Tuomala markku, Calonius Kim, Lastunen Auli, Hyvärinen Juhani, Myllymäki Jukka

Nuclear Energy and Engineering

Safety, Risk, Reliability and Quality

Civil and Structural Engineering

LUT School of Energy Systems

Dryout heat flux experiments with deep heterogeneous particle bed

2006

Publication type

A1 Journal article (refereed), original research

Author(s)

Lindholm Ilona, Holmström S, Miettinen J, Lestinen V, Hyvärinen Juhani, Pankakoski P, Sjövall H

Numerical and experimental studies on impact loaded concrete structures

2006

Publication type

A4 Conference proceedings

Author(s)

Saarenheimo Arja, Hakola Ilkka, Kärnä Tuomo, Hyvärinen Juhani, Tuomala Markku

Nuclear Energy and Engineering

Safety, Risk, Reliability and Quality

Civil and Structural Engineering

LUT School of Energy Systems

Biography

Research interests

Researcher information

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