é um caminho que desperta crescente interesse, quer seja por sua real utilização nos espaços formais de ensino, quer seja pelos trabalhos de pesquisa em ensino apresentados à comunidade. O uso crítico e referenciado das TIC pode colaborar com uma aprendizagem mais efetiva e potencializar oportunidades de uma educação para a emancipação e a autonomia, especialmente quando conjuga qualidade acadêmica e tecnologias livres. Nesse sentido, destacamos a importância da realização de atividades experimentais significativas em aulas de física mediadas por tecnologias educacionais livres que apresentam, ao mesmo tempo, qualidade, flexibilidade de uso e baixo custo, de modo que sejam compatíveis com a realidade educacional brasileira. Para contem-+ Video analysis with the free software Tracker for the laboratory in Physics education: parabolic motion and Newton's second law

No abstract

A laboratory study has been conducted on the use of chemical plugs, instead of conventional mechanical packers, to isolate water and gas-producing zones in horizontal wells. Results of experiments using horizontal wellbore models, consisting of PVC pipes internally lined with sand, indicate that slumping of the chemical plug could be avoided if the plug were spotted in a viscous brine pill. Of the three chemicals tested, a monomer, a polyacrylamide, and a plastic, only the plastic plug had a sufficiently high holding pressure. Research is being continued using a full-scale horizontal wellbore model.

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractIn general, a horizontal well is more productive than a vertical well, due to the fact that there is a larger area of contact with the reservoir and that there is less pressure drop per unit of length in the production section.

TX 75083-3836, U.S.A., fax 01-972-952-9435. ProposalCurrently, the study of naturally fractured reservoirs represents a constant-growing technology because of the high amount of this type of behavior in many reservoirs worldwide. Therefore, for an efficient exploitation is necessary to adequately model them, so a more realistic fracture-matrix flow behavior can be obtained and identified. However, by inspecting some well pressure tests, anomalous slope changes during a matrix-controlled flow period are observed. This behavior does not follow the one described by a dual porosity model.Throughout the years, the pressure transient behavior of naturally fractured reservoirs has been extensively studied. Customary, dual porosity models have been widely utilized to describe the flow behavior taking place in the fracture/matrix system of naturally fractured reservoirs. However, a remarkable flaw of these models is their assumption of homogeneous matrix properties through the whole system. Recently, pseudosteady-state and transient-state triple porosity models have been introduced to take into account the existence of two domains in the matrix with different properties and one domain in the fracture net. There is no flow between the two matrix domains. On a semilog plot of pressure versus time, three parallel straight lines are observed when one domain has lower storativity and higher interporosity flow coefficient. Well pressure analysis for such systems was conducted using the conventional method or semilog type-curve matching.In this study, pressure derivative is applied to triple porosity reservoirs so their typical characteristics and fingerprints are reported. A technique to analyze pressure and pressure derivative data without using type-curve matching is also provided. This technique uses characteristics lines, characteristics points and features found on the pressure and pressure derivative plot to obtain analytical expressions for a practical estimation of permeability, skin and the fundamental parameters of such systems. The proposed methodology was successfully verified by its application to field data cases and simulated pressure data.