Disclosed is a space cold gas thruster operating with a solid propellant. The cold gas thruster includes a tank suitable for containing a solid propellant and a tank heating device suitable for sublimating the solid propellant and forming gaseous propellant, the tank having an aperture for transferring the gaseous propellant outside the tank, such as a nozzle. Also disclosed is a process for determining the amount of remaining propellant in the propellant tank of the disclosed cold gas thruster.

This application addresses a wireless system for the determination of the height of liquid or molten metal levels containing metal, shaft, matte or slag in smelting furnace. Specifically, it addresses a wireless system that allows, without the presence of cables, the sending and receiving of a signal outside of the smelting furnace, in order to determine, on-line, the height of the phases, including the height of the slag-matte interface and the total level of the bath.

A fluid sensor system detects one or more performance characteristics of a heating system that heats a fluid. The sensor system includes a probe having a finite length a portion of which is to be immersed in the fluid. The probe includes a resistive heating element and a fluid temperature sensor for measuring one or more performance characteristics, wherein the fluid temperature sensor is configured to measure a fluid temperature, and the resistive heating element is operable as a heater to create a temperature differential between the fluid and air to detect the fluid, and as a sensor to measure a fluid level.

An autonomous spacecraft propellant-gauging system, the system including a propellant tank, one or more heating devices, at least one temperature sensor and a processor. The heating devices are used to heat up the propellant tank, and the temperature sensors sense the temperature of the propellant content of the propellant tank. The processor controls operations of the heating devices and the temperature sensor. The processor further executes an algorithm to automate gauging of the propellant content of the propellant tank based on a reduced order model (ROM) and a number of parameters, and reports out an estimate of the mass of the remaining propellant of the propellant tank.

A gearbox includes a housing including a lubricant reservoir, at least one gear system arranged in the housing, at least one lubricant delivery passage operable to direct a flow of lubricant from a lubricant reservoir onto the at least one gear system, at least one lubricant return passage operable to guide the flow of lubricant to the lubricant reservoir, and a lubricant-out sensor fluidically connected to the at least one lubricant return passage. The lubricant-out sensor is operable to detect a non-pressure based parameter of the lubricant.

In a method for operating a heating device, fluid is initially introduced into a fluid chamber, then the heating elements of the heating device are switched on and a leakage current is detected as a temperature-dependent current flow through a dielectric insulation layer. A supply voltage of the heating devices is measured and is taken into account in an evaluation of the temperature at the fluid chamber as a function of the leakage current. The leakage current is converted into a leakage voltage by means of a resistor, which is then divided by the measured supply voltage. Subsequently, the quotient obtained may be multiplied by a compensation value in order to obtain a normalized leakage signal, which is normalized to a base value of the supply voltage. The normalized leakage signal is used, if a particular absolute value of the leakage signal is exceeded or if a particular slope of the profile of the leakage signal is exceeded, in order to top up the fluid chamber with more fluid and/or to reduce the heating power of at least one heating element.

A liquid level detection device that is provided in a vessel and configured to detect a liquid level of fluid stored in the vessel includes a first plate formed in a plate shape, and a second plate formed in a plate shape and disposed to face the first plate. The first plate is disposed in such a manner that a surface opposite to a surface facing the second plate is orthogonal to a flow direction of fluid around the first plate in the vessel.

A device for monitoring a liquid level of a liquid storage tank for a vehicle is capable of improving sensing sensitivity of a liquid level sensor by employing a structure capable of amplifying an electromotive force, which is generated by an electrode, at an electromotive force amplification layer including a carbon micro coil (CMC) and accurately sensing a frozen state of a liquid to perform a heating function so as to resolve the frozen state of the liquid.

A method for measuring a liquid level (L) in a pressure vessel (2) the method comprising: providing a thermometric well (10) inside the pressure vessel, heating an inner surface of the thermometric well which is not in contact with the fluid, detecting the temperature of at least one detection point of said inner surface; estimating a position of the liquid level based on the difference between a reference temperature and the temperature so detected.

A heater system includes an integrated heater device and a control system. The integrated heater device includes a thermocouple for measuring temperature and one or more multiportion resistive elements that are operable as heaters to create a temperature differential between the fluid and air to detect the fluid, and as sensors to measure a fluid level. The control device operates the integrated heater device as a sensor or heater based on one or more performance characteristics of the heater system and self-calibrates the heater device.