ARS Upgrade
Upgrade of the IAEA Advanced Reactor Simulation
Software and Training Material.
The International Atomic Energy Agency (IAEA) is assisting
developing countries, by the use of reactor simulation, to get
experience in the operation of nuclear power plants. The principal
objective is to make a "desk top" simulator and a training
material available to all Member States, to assist in their comprehension
and training programs for nuclear power.
This project will provide insights and understanding of the
designs as well as a clear understanding of the operational characteristics
of the various reactor types. It requires an emphasis on the
basic principles of the operation of each reactor type.
On 8 August, 1996, IAEA retained Dr. Li-Chi Cliff Po of U.S.A.
and granted him a Contractual Service Agreement (BC: 100 5050
5410 221 191 A305 D WATER 96CL9125) to prepare the training material
for Advanced Reactor Simulation. Dr. Po shall also install the
software and carry out the training course in 1997.
Three workshops have been conducted so far: the first from
8 to 13 of November, 1997, in Cairo, Egypt, the second from 16
to 21 of November, 1997, at the IAEA office in Vienna, Austria,
and the third from 29 of May to 3 of June, 1998, in Jeddah, Saudi
Arabia. Additional workshops have been planned for the latter
half of 1998 in Trieste, Italy and Korea. The software package
has been distributed to scores of users in 31 countries.
The first part of the Training Package will be the background
material. It contains the objectives, scope of simulation, and
the principles of operation of each reactor type. It explains
the physical principles of a nuclear reactor (power generation
and heat removal). Reactivity and the effect of power, temperature,
void and control mechanisms (i.e. control rods, soluble boron)
on reactivity are to be included.
The second part of the Training Material will be description
of the major water-cooled reactor systems: PWR, BWR and PHWR.
The principle approach to reactor control using these phenomena
for each reactor will be explained. Systems and components designed
to address reactor normal and abnormal operation will be described.
Sensitivity of the different parameters relevant to the reactor
is an important part of this chapter. Consideration of all possible
conditions and events will be made systematically regardless
of the reactor type. Events that may be important in the case
of a BWR should also be discussed for a PWR and shown to be of
no importance and vice versa. The objective of this approach
is to show the fundamental difference between a BWR and a PWR
and the variations in response according to the reactor type.
The third part will be description of the simulated system.
The theory and mathematical models of each reactor type will
be introduced. The objective is to show to the trainee the general
characteristics of a PWR, a BWR or a PHWR, to give him or her
a comprehensive understanding of the simulated systems, and to
provide instructions for use and exercise of the simulation package.
Sample problems will be demonstrated with exercises for diagnosis
of unknown events.
Within the Advanced Reactor Simulator, the PWR and BWR modules
have been working well, (reflecting the fact the contractor has
large contracts with LWR vendors for simulator development).
However, a number of required improvements have been identified
in the PHWR. These improvements, identified in a review of the
code are:
- Remodel the reactivity feedback from both the coolant and
moderator. By adjusting the positive feedback from coolant void,
the kinetics equation will cause a power spike immediately following
a major pike break. This positive feedback induced instability
during normal operation will be compensated by control system
adjustment. A simplified mechanistic model consistent with the
CANDU design will be formulated.
- On System 2 scram, the strength of the Gadolinium solution
will be adjusted so that the power will be less than 15% in 7
seconds after scram initiation.
- The Advanced Reactor Simulator training material will be
modified to reflect the changes.
If your country is a member state of IAEA and you are interested
in IAEA's training program in Advanced Reactor Simulation, please
contact your country's representative or the IAEA directly or
Mr. Robert Lyon (R.Lyon@iaea.org)
of IAEA. |
