A method for estimating an amount of cryogenic fluid in a cryogenic fluid supply vessel comprises releasing pressure from the cryogenic fluid supply vessel at a predetermined frequency via a control valve. The method also comprises detecting a disturbance in an output signal of a pressure feedback sensor. The disturbance occurs at the predetermined frequency. The method additionally comprises determining a magnitude of the disturbance in the output signal of the pressure feedback sensor and estimating the amount of the cryogenic fluid in the cryogenic fluid supply vessel based on the magnitude of the disturbance in the output signal of the pressure feedback sensor.

A method for ascertaining the re-starting capability of a vehicle, in particular when parking the vehicle, includes detecting the pressure and the temperature of fuel in a pressurized container, determining a final pressure value of the fuel in the pressurized container, where the final pressure value is an expected pressure of the fuel in the pressurized container after a period of parking of the vehicle, comparing the final pressure value with a minimum pressure value in order to ascertain whether the vehicle is capable of re-starting after the parking period, and generating a warning signal when the final pressure value is lower than the minimum pressure value.

An amount Y of liquid hydrogen that has passed through a first valve and has been volatilized during a predetermined time after first and second valves are opened is calculated by using a pressure P0 in an internal space of a liquid hydrogen tank measured before the two valves are opened, a pressure P1 in the internal space measured after the lapse of the predetermined time since the two valves are opened, and an amount X of the gaseous hydrogen that has passed through the second valve during the predetermined time. A fluid level H of the liquid hydrogen in the liquid hydrogen tank after the lapse of the predetermined time since the two valves are opened is calculated by using a expression showing a relationship between the H and an amount Y1 of the liquid hydrogen that passes through the first valve and drops therefrom, and the Y.

A method and apparatus for compressing gases and supplying fuel to a gaseous fuel consuming device, such as a gaseous fueled vehicle or the like. One embodiment includes a gas compressor for compressing the gaseous fuel to an array of tanks having predetermined initial set points which are increasing for tanks in the array. One embodiment provides a selecting valve having first and second families of ports wherein the valve can be operated to select a plurality of ports from the first family to be fluidly connected with a plurality of ports with the second family, and such fluid connections can be changed by operation of the valve.

A hydrogen filling station accounts for variabilities between tank systems when filling compressed gas tanks. To identify a theta value that accurately reflects the conditions and performance of a particular tank system, one or more test parameters are determined, and one or more margins associated with one or more test fills of a fuel tank are identified, where each test fill corresponds to a respective test parameter. A proposed theta value for controlling one or more fuel deliveries to the fuel tank is determined based on the test parameters and the margins. In this manner, the theta value enables hydrogen refueling of a compressed gas tank to be improved.

A tank state estimating method of estimating a state in a tank at a predetermined point in time on a sailing course of an LNG carrier is provided. The LNG carrier carrying LNG stored in the tank as a cargo. The tank state estimating method includes: a first step of acquiring information related to specification of the tank; a second step of acquiring information related to a state in the tank at a start point of a target section on the course; a third step of acquiring information on a predictive value of liquid fluctuation of the LNG in the tank during the section, the predictive value being obtained on a basis of a weather forecasting value during the section and information on the weather forecasting value; and a fourth step of calculating the state in the tank at an end point of the section by thermal transfer calculation based on thermodynamics on a basis of the information acquired in the first to third steps in assuming that a heat input to the tank during the section is used for vaporization of the LNG in the tank.

A management system includes a position detection unit which obtains a position of a work machine, a posture detection unit which obtains a posture of the work machine, an object detection unit which obtains a three-dimensional shape of a buried object, a position calculation unit which obtains a position of the buried object by using the position of the work machine obtained by the position detection unit, the posture of the work machine obtained by the posture detection unit, and the three-dimensional shape of the buried object obtained by the object detection unit, and an information acquisition unit which acquires buried object information including at least the position of the buried object obtained by the position calculation unit.

A fuel gas filling system detects at least one of a pressure of fuel gas supplied from a filling device and a temperature of the fuel gas in a fuel tank of a vehicle and determines whether or not there is a gas state fluctuation in which the pressure or temperature of the fuel gas suddenly changes. The fuel gas filling system executes either one of a first filling control of filling the fuel gas into the vehicle on the basis of at least one of the fuel gas pressure and the fuel gas temperature and a second filling control according to the gas state fluctuation. This system executes the first filling control in normal time and executes the second filling control of filling the fuel gas without using a fuel gas pressure detected by fuel gas state detection unit or the second filling control of filling the fuel gas without using a fuel gas temperature detected by the fuel gas state detection unit when it is determined by gas state fluctuation determination unit that there is the gas state fluctuation.

The present invention provides a monitoring apparatus for an outlet of a vessel storing gas under pressure. The monitoring apparatus comprises a flow control valve movable to a position between a fully open position and a fully closed position to adjust a flow of gas from the outlet of the vessel, a valve position detector connected to the flow control valve to detect the position of the flow control valve, an internal pressure sensor to sense an internal pressure P.sub.int(t) of the gas in the vessel at different times, a processor, a memory and an alarm. The processor calculates an actual rate of change in pressure dP.sub.int/dt of the gas in the vessel over time, and compares dP.sub.int/dt with an expected rate of change.

A method for filling tanks with pressurized gas via a filling station comprising several storage containers and a fluid circuit for transferring the gas from the containers to the tanks, the circuit comprising a first end to which the containers are linked in parallel and a second end provided with a transfer line intended to be connected to the tank(s) to be filled, the circuit comprising, arranged in series between the first end and the second end, a first isolation valve, a flow or pressure regulation member, and a second isolation valve, the method comprising filling a first tank, characterized in that, on completion of the filling of the first tank and before filling a second tank, the first and second isolation valves are closed to trap a supply of pressurized gas in the circuit between said two valves and in that the supply of gas is used to refill at least one of the containers.