[en] The ''Instituto de Asuntos Nucleares'' of Colombia is responsible for IAN-R1 reactor operation, a 20 Kw. nuclear power machine, which became critical the first time on January 20th, 1965. The introduction of nuclear energy in Colombia has allowed to carry out many peaceful applications, where the reactor has played a significant role in support of these programmes. At this time, the main activities are: Educational and training activities; nuclear research; neutron activation analysis; delayed neutron analysis and radioisotopes production for using in agriculture, industry, hydrology and engineering. A description is made of the reactor aspects that have contributed to scientific and technological improvements

[en] The Reactor Group used the code WIMS reduced to five groups of energy, together with the code CITATION, and evaluated four configurations for a core, according to the grid actually installed. The four configurations were taken from the two proposals presented to the Instituto de Ciencias Nucleares y Energias Alternativas by General Atomics Company. In this paper, the Authors selected the best configuration according to the performance of flux distribution and excess reactivity, for a TRIGA core to be installed in the Nuclear Reactor IAN-R1

[en] The program to modernize IAN-R1 research reactor control and safety instrumentation has been carried out considering two main aspects: updating safety philosophy requirements and acquiring the newest reactor control instrumentation controlled by computer, following the present criteria internationally recognized, for safety and reliable reactor operations and the latest developments of nuclear electronic technology. The new IAN-R1 reactor instrumentation consist of two wide range neutron monitoring channels, commanded by microprocessor a data acquisition system and reactor control, (controlled by computers). The reactor control desk is providing through two displays; all safety and control signals to the reactor operators; furthermore some signals like reactor power, safety and period signals are also showed on digital bar graphics, which are hard wired directly from the neutron monitoring channels

[en] Infinite multiplication factor (Kinfinity) is calculated for research Reactors with MTR fuel type. Linear approximation for neutron flux in the cladding is utilized. The behavior of some typical parameters for IAN-R1 Reactor are shown when fuel enrichment varies. (author)

[en] Using the Monte Carlo Method a computer program has been developed to simulate the neutron radiation transport and determine the basic parameters in shielding calculations. The program has been tested comparing dose conversion factors with kerma factors issued by the international commission on radiation units and measurements (ICRU) on its report (No 26 of 1987) giving errors less than ten percent showing the goodness of the method. The program computer transmitted backscattered and absorbed flux on energy less on each collision. when neutrons are produced by region source with knowing energy; results are given like conversion factors and reliability of this program allows a wide application on radiological and medical physics

[en] With cooperation of the International Atomic Energy Agency (IAEA), thermal-hydraulic calculations were carried out for conversion of the IAN-R1 Reactor from MTR-HEU fuel to TRIGA-LEU fuel. To establish thermal-hydraulic calculation and analysis research in Colombia, this program was carried out and included training, acquisition of hardware, software and natural convection flow calculations for the TRIGA IAN-R1 research reactor operating at 100 kW. The purpose of the study is to validate the steady state thermal hydraulic analysis that has been carried out by means of the NATCON code. This paper presents the results of the maximum axial temperature distribution for fuel, clad, and coolant. In addition, the Bernath critical heat flux with pool water temperature as a parameter is presented.

[en] Calculation methods for radiation heat generation in nuclear reactor, based on the point kernel approach are revisited and applied to the graphite reflector of IAN-R1 reactor. A Fortran computer program was written for the determination of total heat generation in the reflector, taking 1155 point in it

[en] The Instituto Nacional de Investigaciones Nucleares (ININ) participated in an international tender published by the Colombian Geological Service for the modernization of the Nuclear Reactor Control Console Ian-R1, the participating institutions were: General Atomics (USA), INVAP (Argentina) and ININ (Mexico). The proposal made by the ININ had an important characteristic, the independence of the manufacturer, since it was a project based on modular elements. One of the elements was the Human-Machine Interface (HMI), where the development was proposed under the Free Software (Gnu-GLP) scheme. Java was the programming language on which the HMI was developed to operate the nuclear reactor in Bogota, Colombia. The instrumentation that allows the interaction with the sensors and/or actuators is based on the use of PLC's (programmable logic controllers) with which the computers of the HMI communicate through a local network using the Mod bus protocol over Ethernet. (Author)