Flow Regime Identification Methodology with Mcnp-X Code And Artificial Neural Network

This paper presents flow regimes identification methodology in multiphase system in annular, stratified and homogeneous oil-water-gas regimes. The principle is based on recognition of the pulse height distributions (PHD) from gamma-ray with supervised artificial neural network (ANN) systems. The detection geometry simulation comprises of two NaI(Tl) detectors and a dual-energy gamma-ray source. The measurement of scattered radiation enables the dual modality densitometry (DMD) measurement principle to be explored. Its basic principle is to combine the measurement of scattered and transmitted radiation in order to acquire information about the different flow regimes. The PHDs obtained by the detectors were used as input to ANN. The data sets required for training and testing the ANN were generated by the MCNP-X code from static and ideal theoretical models of multiphase systems. The ANN correctly identified the three different flow regimes for all data set evaluated. The results presented show that PHDs examined by ANN may be applied in the successfully flow regime identification.

Preparation of Excitation Sources to Portable X-Ray Spectrometer by Recovering 241am from Radioactive Lightning Conductor

With the prohibition of the use of radioactive lightning conductor in Brazil, this material passed to be collected and stored as radioactive waste in the waste deposits of The Brazilian National Nuclear Energy Commission (CNEN). The majority of these lightning conductor used as radioactive source 241Am with activity varying of 1 the 5 mCi. In this work are presented preliminary studies by recovering of 241Am through the electroplating technique, in order to posterior use as sources to portable X-rays fluorescence spectrometer. The 241Am sources have been removed from lightning conductor and dissolved in acid solution. The solution presented an activity of 0,6 Ci L-1. Small amounts of this solution were added to some electrolytes and tested in order to evaluate optimum electrolyte for deposition of 241Am. It was studied as electrolytes: HNO3 (0,2 mol L-1), NH4Cl (5,0 mol L-1) and a mixture of KCN and K2CO3 (in the rate of 2,0 g of each per liter). Yields of up to 90% were obtained applied a current density of 50 mA cm-2.