A gas injector apparatus and method for use with a tracer gas airflow measurement system that allows for large, continuous tracer gas flow rates while avoiding operation at very cold temperatures that will damage equipment. The controlled and variable heating of high pressure tracer gas flow before a gas regulator allows all points in the system to remain above freezing, and within a safe temperature range. The system has a tracer gas source and a heater that heats the gas isobarically at high pressure (>100 psi) and the hot gas is expanded across a pressure regulator to a lower working pressure to 30 psi. The gas flow is modulated using a mass flow controller with a high turndown ratio and injected into a bulk fluid flow with an injector.

A system and method for remote detection, marking and/or sealing leaks in pipe or duct networks are provided. Aerosolized sealant particles that have a surface tackiness that diminishes over time are introduced into the pipe interior. A pressure differential is created and the micron scale particles adhere to the leak edges and to other particles as they are brought to the leaks and then leave the gas streamlines. Control of particle size, drying rate and particle residence time in the pipe interior allows control over the treatment area so that leaks are sealed in the pipes without sealing purposeful openings such as pilot lights or gas valves. This control also produces seals in duct systems with minimal tack at the time the duct systems are returned to service. Particles that do not participate in the formation of a seal can be collected or flushed through the system.

A leak detection system for a refrigerant circuit is provided. The refrigerant circuit is sealed and circulates a working fluid having a refrigerant (e.g., flammable refrigerant) and an oil. A reducing tag component is solubilized within the refrigerant. The leak detection system also includes a sensor for detecting the tag component if the refrigerant should leak from the refrigerant circuit. The sensor is highly sensitive to the tag component and thus enhanced detection is enabled. The tag component is stable in the working fluid and does not affect the flammability rating or performance of the refrigerant or oil. The tag component is present at a concentration of from about 50 ppm to about 35,000 ppm in the refrigerant. Methods of detecting leaks from refrigeration systems are also provided.

A method for determining correct performance of a sampling pipe in an aspirated particle and/or gas sampling system. The method includes causing a change in airflow n a sampling pipe of the aspirated particle and/or gas sampling system that induces a change in at least one airflow property within the sampling pipe, and detecting an effect of the change in said airflow property. Also disclosed is a method for determining correct performance of an aspirated particle gas sampling system. The method includes determining correct performance of a sampling pipe in the aspirated particle and/or gas sampling and determining correct performance of a detector in the aspirated particle and/or gas sampling system, wherein a test fluid is introduced to the aspirated particle and/or gas sampling system at or near the detector.

A system and method for monitoring a flow of a fluid on an external surface of a structure in motion. The structure defines an external side comprising the external surface and an internal side opposed from the external side. The system comprises a fluid dispensing device located on the internal side of the structure. The fluid dispensing device comprises the fluid and a conduit that directs the fluid onto the external surface of the structure. An observation device is located on the external side of the structure. The observation device is positioned to observe the flow of fluid on the external surface of the structure.

A fitting assembly includes a fitting comprising a housing and a connector assembly arranged within the housing. The connector assembly comprising a hollow interior and configured to be movable between an unactuated position and an actuated position. In the actuated position, the connector assembly is connectable to a pipe receivable within the hollow interior. An adapter coupled to the fitting includes a biasing mechanism configured to bias the connector assembly from the actuated position to the unactuated position.

A sodium leak detection system for a nuclear reactor vessel includes a recirculation loop having an inlet and an outlet in communication with the annular space between the nuclear reactor vessel and the guard vessel. The recirculation loop and the annulus are filled with an inert gas, such as argon. The inert gas is doped with a known trace quantity of oxygen, typically in the single-digit ppm range up to about 1%. A recirculator forces the inert gas and oxygen to mix and flow throughout the annulus. The recirculation loop further includes a trace oxygen sensor that determines the concentration of oxygen in the inert gas. Because sodium reacts with oxygen, the trace oxygen sensor is monitored for a reduction in the oxygen level, which indicates a sodium leak into the annulus.