Abstract: A method and system for controlling the rate of fluid flow. A flow restrictor having known pressure drop and flow rate characteristics provided in a passage through which the fluid, preferably a gas, flows. An upstream pressure sensor determines the pressure of fluid in the flow passage upstream of the flow restrictor. A downstream pressure sensor determines the pressure of fluid in the flow passage downstream of said flow restrictor. A pressure regulator adjusts the pressure of fluid upstream or downstream of the flow restrictor based on the pressure drop across the flow restrictor so that the actual pressure drop across the flow restrictor closely corresponds to the pressure drop associated with a desired rate of fluid flow.

Abstract: A method and system for controlling the rate of fluid flow. A flow restrictor having known pressure drop and flow rate characteristics provided in a passage through which the fluid, preferably a gas, flows. An upstream pressure sensor determines the pressure of fluid in the flow passage upstream of the flow restrictor. A downstream pressure sensor determines the pressure of fluid in the flow passage downstream of said flow restrictor. A pressure regulator adjusts the pressure of fluid upstream or downstream of the flow restrictor based on the pressure drop across the flow restrictor so that the actual pressure drop across the flow restrictor closely corresponds to the pressure drop associated with a desired rate of fluid flow.

Abstract: A method and system for controlling the rate of fluid flow. A flow restrictor having known pressure drop and flow rate characteristics provided in a passage through which the fluid, preferably a gas, flows. An upstream pressure sensor determines the pressure of fluid in the flow passage upstream of the flow restrictor. A downstream pressure sensor determines the pressure of fluid in the flow passage downstream of said flow restrictor. A pressure regulator adjusts the pressure of fluid upstream or downstream of the flow restrictor based on the pressure drop across the flow restrictor so that the actual pressure drop across the flow restrictor closely corresponds to the pressure drop associated with a desired rate of fluid flow.

Abstract: A method and system for controlling the rate of fluid flow. A flow restrictor having known pressure drop and flow rate characteristics provided in a passage through which the fluid, preferably a gas, flows. An upstream pressure sensor determines the pressure of fluid in the flow passage upstream of the flow restrictor. A downstream pressure sensor determines the pressure of fluid in the flow passage downstream of said flow restrictor. A pressure regulator adjusts the pressure of fluid upstream or downstream of the flow restrictor based on the pressure drop across the flow restrictor so that the actual pressure drop across the flow restrictor closely corresponds to the pressure drop associated with a desired rate of fluid flow.

Abstract: A method and system for controlling the rate of fluid flow. A flow restrictor having known pressure drop and flow rate characteristics provided in a passage through which the fluid, preferably a gas, flows. An upstream pressure sensor determines the pressure of fluid in the flow passage upstream of the flow restrictor. A downstream pressure sensor determines the pressure of fluid in the flow passage downstream of said flow restrictor. A pressure regulator adjusts the pressure of fluid upstream or downstream of the flow restrictor based on the pressure drop across the flow restrictor so that the actual pressure drop across the flow restrictor closely corresponds to the pressure drop associated with a desired rate of fluid flow.

Abstract: An optical probe is sealingly mounted in an access port of a pressurized container. The probe comprises a glass rod of a predetermined thickness having a conical end tip. An optical transmitter and receiver is connected to the glass rod. The fiber optic transmitter and receiver sends visible red light down the glass rod. When the liquid level inside the container drops below the end tip of the glass rod, reflected light will be received from the glass rod and detected.

Abstract: A tube is attached inside a container and forms an inlet aperture. A transparent bulb is sealed over the end of the tube. A fiber optic probe is inserted into the tube and bulb. The fiber optic probe is connected to a fiber optic transmitter and receiver, which sends a beam of light down the probe. The beam of light reflects off the contents of the container and the reflected light is received by the fiber optic probe. The fiber optic transmitter and receiver compares the light intensity of the reflected light with the light intensity of the light beam. Changes in this radio indicate there has been a change in the contents of the container.