PCTRAN is the most successful desktop simulator for all types of light water nuclear reactors. It is specifically designed for many different plant types, including PWR, BWR, advanced AREVA EPR, Westinghouse AP1000, GE ABWR, and ESBWR. PCTRAN's simulation scope extends to severe accidents and dose dispersion. Since its first introduction in 1985 by Micro-Simulation Technology, PCTRAN has been selected by the IAEA as the training platform for its annual Advanced Reactor Simulation workshop. Plant-specific models have been installed at nuclear power plants and institutions all over the world for practical application in training, analysis, probabilistic safety assessment, and emergency exercises.



The Russian VVER-1200 (NPP-2006 or AES-91) is the version currently offered for export. Right now there are active projects in China, India, Bangladesh, Bulgaria, Jordan and Egypt It is an evolution of the VVER-1000 with increased power output to about 1200 MWe (gross) and providing additional passive safety features.  The PSAR (Preliminary Safety Analysis Safety Report) of model 392M under construction at the Novovoronezh NPP-II is used for developing and benchmark of the PCTRAN simulator.


NuScale SMR

NuScale power module consists of a small 160 MWt reactor core housed with other primary system components in an integral reactor pressure vessel and surrounded by a steel containment vessel, which is immersed in a large pool of water. Above the core is a central hot riser tube, a helical coil steam generator surrounding the hot riser tube, and a pressurizer. The helical coil steam generator consists of two independent sets of tube bundles with separate feedwater inlet and steam outlet lines. A set of pressurizer heaters and sprays is located in the upper head of the vessel to provide pressure control.

PCTRAN simulator follows NuScale design closely by setting the module in the middle. The chemical and volume control system (CVCC), decay heat removal system (DHS), reactor protection system (RPS) and containment control panels are at left.  The pressurizer, turbine and steam generators, and reactor core control are at right hand side.


The purpose of this PC-based simulator is not just for the control room operator training, but also for prospective clients in their evaluation of the technology.  They learn how the passive-cooled inherent safe SMR works.  In a quantitative and dynamic hand-on practice, the reactor performs well in startup, load control, electricity generation and desalination water production. They may also practice any combination of accident scenarios including feed and steam line breaks, SG tube leak, up to the most challenging Fukushima type station blackout up to 30 days – without any possibility of damage to the core or dose release.

SMART is a 330 MWt pressurized water reactor with integral steam generators and advanced safety features.  The unit designed by Korea Atomic Energy Research Institute (KAERI) for electricity generation (up to 110 MWe) as well as thermal applications such as seawater desalination.  


The PC-based simulator PCTRAN for SMART was developed using experience gained on work for the Korean APR1400 and OPR1000.  Both are licensed to Korea Institute of Nuclear Safety (KINS), Korea Electric Power Co (KEPCO), Korea Hydro and Nuclear Power (KHNP) and five universities in Korea.  SMART has its unique in-vessel pressurizer, helical coil once-through-steam generators, and canned circulation pumps. It is equipped with both active and passive heat removal systems.  In the event of a severe accident resulting hydrogen in the containment, there are passive auto-catalytic recombiners to reduce its concentration. They are all closely simulated for training and education. 


The reactor could use all its steam for electricity generation for a total of 110 MWe, or extract the steam at its low-pressure turbine to a MED-TVC plant for desalination.  The electricity output will be reduced to 90 MWe with 40,000 tons of fresh water production per day.  Combined the plant could support a 100,000 population city’s consumption.

The multiple effect distillation (MED) with thermal vapor compressor (TVC) has a gain output ratio (GOR)  about 13 for the distilled water to the motive reactor steam.


A complete line of normal and accidental cases have been conducted.  It includes normal startup, power escalation, shutdown and cool-down using normal HCSG and shutdown cooling system, loss of coolant accidents and station blackout (SBO) Fukushima type accident. Despite core damage and hydrogen generation is virtually impossible to occur, the simulator is capable to perform an intentional loss of passive RHR cooling event with hydrogen in the containment.  Then start of the PAR suppresses the content to non-combustible level.



EPR Severe Accident

The EPR includes a number of unique features to prevent or mitigate the effects of severe accidents:

  1. In-containment refueling water storage tank (IRWST),
  2. Severe accident heat removal system (SAHRS).
  3. Combustible gas control system (CGCS),
  4. Core-melt stabilization system

PCTRAN/EPR as a PC-based trainer, has all above systems and their respective functions modeled in dynamic simulation. As a result, students learn severe accidents and EPR’s unique system for mitigation. 


Post-Fukushima "Stress Test" and FLEX methodology extend defense-in-depth to beyond the design-basis and external events. PCTRAN is the only simulator that provides fast-time training and exercise. Additional portable power suppy, water souce, alternate cooling means, etc. can be easily incorporated. Panel display mimics the actual Plant Comuter System (PCS) for enhanced training .

Recent (2014) Licensees

Korea Hydro & Nuclear Corporation (KHNP) Center of Research Institute (CRI) has acquired PCTRAN KSNP and APR1400 severe accident models via FNC, Inc.

Chattanooga State Technical Community College has acquired RadPuff for radiological dispersion projection.

Tohoku University of Japan has acquired PCTRA/BWR5 severe accident model vis CSA of Japan for its training and education.

Kyushu University of Japan has acquired PCTRA/PWR 4-loop severe accident model vis CSA of Japan for its training and education.

King Abdu LaZiz University of Saudi Areabia has acquired generic PWR model for training and education for the kingdom's plan of constructing up to 16 power plants.

Contact us

Free Downloads -- BWRs, PWRs, Severe Accident, Dose Assessment

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ESBWR GE/Hitachi Economic Simplified BWR
PCTRAN Personal Computer Transient Analyzer (PWR and BWR, Detailed Verification in Download Packages)
ABWR Advanced Boiling Water Reactor
TRIGA Experimental Pool Reactor Simulator
SFP Spent Fuel Pool Accident Simulator
AP1000 Westinghouse AP1000 New Cold Startup & Shutdown
Areva EPR New severe accident capability to show core-melt and containment failure and Cold Startup & Shutdown
Korean KSNP Korean OPR (KSNP1000) and APR 1400 with severe accidents
VVER Russian-designed PWR with horizontal SG's with severe accidents
CPR-1000 Three-loop PWR

High Temperature Gas Reactor

APWR Mitsubishi APWR (New)
NHR Nuclear Desalination Reactor
Fukushima BWR4 or 5 for Fukushima event (New)

New Korean APR1400 & OPR1000

MST has successfully developed PCTRAN for KSNP1000 and APR1400. By arrangement with our distributor in Korea - FNC Technology, the APR1400 severe accident and RadPuff model is licensed to Korea Institute of Nuclear Safety as a research project. The OPR model is licensed to Jeju University and YeoungNam University for education. Free Download

The first APR1400 will be operational in Shin-Kori 3 and 4 soon in Korea. An APR1400 is also slated for construction in the UAE.

Note following the lessons learnt from the Fukushima event, passive hydrogen recombiners and ignitors have been incorporated and in-vessel retentrion strategy is investigated.

Purdue University

The Polytechnic University of Madrid

The City College of New York

US Naval Academy

Fleet of Software for Radiological Emergency

The Fort Calhoun Station of Omaha Public Power District and Comanche Peak Plant of Luminant Power have upgraded their PCTRAN applications with spent fuel pool and area dose projection features. The severe accident scenarios now cover hydrogen burn, directing LOCA sump water into reactor cavity to cool vessel failure debris, outside containment LOCA ("V" event), etc.

New Mitsubishi APWR

Recent Paper Publications


New Video Demonstration of PWR Steam Generator Tube Rupture (18 minutes)

Startup and Shutdown

Capability of startng up a reactor from cold to criticality, rolling the turbine and synchronising with the generator grid is added into PCTRAN series of simulators.

New Plant Training in Nuclear Engineering International November 2008 issue

New features:

Nuclear Desalination Plant

Micro-simulation Technology developed a simulator for a 200MW low temperature heating reactor NHR designed by Tsinghua University of China for desalination.  The nuclear plant is coupled with a MED-TVC (multiple effect distillation – thermal vapor compression) unit to generate distilled water.  Point kinetics is used to solve core power evolution from cold to critical and power conditions. The steam generated by the nuclear plant is directed to four parallel units of MED-TVC.  Using fourteen vacuum chambers (effects) to evaporate the steam with a compressor, this MED-TVC process reaches a gain output ratio (GOR or distilled water production / nuclear steam rate) of over 15.  The fresh water production is 120,000 tons per day. We have also completed a simulator for another type of desalination device - VTE or vertical tube evaporation - that reaches a higher production of 160,000 tons of pure water per day.

The simulator facilitates training and design for plants such as these that are optimized for regions with low fresh water supplies.  It also serves as a useful tool in studies of economic feasibility and cost. Free Downloads


Can a NPP become a WMD?

Can a nuclear power plant become a weapon of mass destruction by accident or sabotage?  Well, the highly radioactive core and spent fuel inventory is hazardous if released to the environment on a large scale.  The possibility cannot be ruled out so that the US Army Combating WMD Agency (USACWMD) has acquired two of our basic simulator modules - one PWR and one BWR to train its staff.  A training course will cover all possible accidents and their impact to public safety. 

Exactly for the same idea the Hong Kong government and the Defense Laboratories DSO of Singapore are prepared for possible radiological events originated either inside or beyond their territories. Training sessions were conducted in late July of 2012. We have also licensed to State Radiation Protection Agencies of New Jersey and Pennsylvania. So look out DHS and states' colleagues, you'll find the right stuff right here.


Copyright 2012 All Rights reserved.

All contents in this website, including text, picture images and free download software are property of Micro-Simulation Technology. It is solely for individual's use for information only. Without a written permission by MST, no part is allowed to be re-distributed or used for profitable or non-profitable gains by any individual or organizations.



New online data acquisition and consequence projection system assures no mega-disasters ever again


With the aftermath of the 1979 Three Mile Island event, every plant in the world followed the US’s lead of installing a so-called Safety Parameter Display System (SPDS), which transmits key plant operations data to offsite support centers for emergency support and response.  So in principle a large pool of superior technical resources is available around the clock to mitigate an event’s severity.  Yet this did not prevent the tsunami-caused damage to the Fukushima units from evolving into a major disaster.  The reason is that despite awareness of the plant’s condition, the support staff did not have a robust means for projecting its consequences nor come up with plausible solutions.  

Over the sixty years development of the world nuclear power industry, there have been no shortage of sophisticated computer analysis tools and replica training simulators capable of transient simulation.  However, during the first weeks or so of the Fukushima accident, none were capable of predicting or reproducing the four Daiichi units’ outcome that could lead to meaningful mitigation measures. With the exception of Micro-Simulation Technology’s PCTRAN BWR3 and 4 models, within days we were able to provide explanations for the events that transpired and post the results online.  Our analysis turned out to be the only thing credible. It is highly consistent with what was announced by the IAEA and Japanese authorities (see later details below). 

Owing to the PCTRAN model’s relative simplicity yet high degree of fidelity in modeling each and every specific NPP, the technology is mature enough to construct an “Online NPP Incident Projection System”. 

By using a selected subset of real-time plant data, anything exceeding a pre-determined 2nd level such as “Alert” in the US four Emergency Activation Level (EAL) system will be automatically downloaded onto a dedicated PC and warning is sent to mobilize the supporting analyst team.  The team will perform faster-than-real-time projection of the event using various mitigating routes.  The best solution will be recommended to the control room crew.  Should there be core-melt or dose release, the source term and dose distribution will be immediately reported to higher authorities.

Using existing Internet-based SPDS, MST is working with a few NPPs to build the first online pilot systems.  Since each key component is already handy, within months it will be ready for testing. 



© 2007 Micro-Simulation Technology