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Traditional slickline work usually encompasses basic mechanical manipulation for downhole intervention work. In the recent past, a variety of battery-powered downhole tools have emerged in the market, providing additional deepwater solutions for the industry. These tools include the extended-reach downhole power unit and the smart release tool. The downhole electrical power unit is an electro-mechanical setting tool that uses a timer activation switch to begin the setting process for a variety of downhole tools. The smart release tool provides a timer-based mechanism to release the deployment wire from the downhole toolstring, eliminating the exposures associated with dropping a cutter in the event of a stuck tool. These tools can be conveyed on slickline for a variety of intervention solutions, including setting tubing plugs and packers, pulling subsea tree plugs, setting pressure gauges in tubing profiles, and providing a mechanical release in highly-deviated, extended-reach wellbores. This paper discusses specific well-intervention case histories using the downhole electrical power unit and the smart release tool. In the first case history, the downhole electrical power unit was used to set a packer assembly during a safety- valve repair. The smart release tool was used to soft set memory pressure gauges in wells without functioning, permanent downhole gauges, eliminating the need for jar action that could damage the gauges. Adaptations were made to the existing tool designs to respond to the well-specific challenges. These case histories demonstrate applications in which the electro-mechanical timer-activated tools have provided solutions for deepwater Gulf of Mexico well-intervention projects. The discussion includes lessons learned from previous project designs, development of operational best practices, and possible future applications to extend the role of slickline in deepwater operations. Applications may include the use of the downhole power unit to set packers and bridge plugs in conjunction with memory logging tools to correlate depth, as well as continued use of the smart release tool to minimize risks associated with downhole mechanical evaluation and memory data acquisition.

This study presents two new methods to rapidly analyze the ignition and combustion events recorded during in-cylinder high-speed imaging of homogeneous charge compression ignition (HCCI) and spark-assisted (SA) HCCI engine operation. Two categories of ignition have been observed during HCCI and SA HCCI: auto-ignition of parcels of fuel/air and ignition and propagation of reaction fronts. In this work, two methods of image analysis are developed which accommodate differences in the ignition and propagation events for the two categories. The methods are described by application to high speed imaging data acquired from an optically accessible engine operated in HCCI and SA HCCI modes using indolene fuel. Using method I, the projected area of reaction is identified in each frame, and a circle with a characteristic radius that yields the equivalent area is defined. The rate of area expansion is used to define the speed of reaction. Using method II, an edge-finding algorithm is used to identify the location of well-defined reaction fronts. The maximum dimensions of the reaction front in an x-y coordinate frame are measured. The projected area based on the average of these maximum dimensions is then determined. The change in the characteristic radius of the projected area is defined as the average propagation speed for the reaction front. The two analytical methods are applied to typical HCCI and SA HCCI image sequences. Outcomes of the image analysis indicate propagation speeds are typically between 2–5 m/s prior to volumetric ignition. Volumetric ignition is identified by propagation speeds greater than 20 m/s. The imaging data also identify times when reaction quenching occurred after spark ignition as times when negative propagation speeds are observed. When applied to the same imaging sequence, the two methods yield consistent results for propagation speeds; however, the method based on edge-finding exhibits larger variance.Copyright © 2010 by ASME