Patent attributes
Methods and apparatus include an expandable packer having a tubing expanded to create a seal in an annulus surrounding the tubing. The tubing includes a non-uniform outer surface configured to cause formation of undulations in a diameter of the tubing upon expansion of the tubing. A plurality of expandable packers may be connected to a tubular string to isolate multiple zones in a wellbore. A production tubular equipped with multiple expandable packers may be installed in the tubular string. The expandable packers may also include non-uniform outer surfaces configured to form undulations upon expansion. The combination of tubular string and production tubular may be used in an enhanced oil recovery application such as injecting steam into a formation to enhance production.