System and method for metering gas

Abstract

The invention discloses a system and method for metering gas. The system for metering gas includes a flow sensor and a controller. The flow sensor is disposed in a conduit in fluid connection with a flow of a gas through the conduit. The flow sensor includes a heater and a temperature sensing element, and generates an electrical output based on the flow of the gas. The controller controls operation of the heater and is operable in a pre-measurement mode and multiple measurement modes. The controller in the pre-measurement mode operates the heater at a pre-measurement setting. The controller in the measurement modes operates the heater at corresponding measurement settings that have increased power levels and / or increased operating durations relative to the pre-measurement setting. The controller in the measurement modes is configured to determine a flow rate of the gas based on an amplitude characteristic and / or a temporal characteristic of the electrical output of the flow sensor.

Description

technical field [0001] Embodiments of the present disclosure relate to measuring fluid flow, and more particularly, to systems and methods for measuring gases. Background technique [0002] Measuring gases currently requires the use of various types of flow sensing devices. For example, mass flow sensing devices measure mass flow rate (e.g., kilograms per second), and other flow sensing devices may include vortex-based sensing, which determines the volumetric flow rate of a fluid based on the frequency of vortex formation (or decay) . Known flow sensing devices include various disadvantages. For example, mass flow sensing devices determine the mass flow rate of gas based on magnitude measurements and do not provide direct volumetric flow rates. While mass flow sensing devices offer the advantage of high sensitivity in the low flow range, the accuracy of such mass flow sensing devices can be adversely affected at higher flow rates by practical considerations such as gas de...

AI Technical Summary

Problems solved by technology

However, current flow sensing devices do not adjust heater settings based on the specific flow parameter being measured, so that the heater can be operated for a longer period of time than necessary, and / or at a higher power level , thus wasting additional energy

Due to inefficiencies in power consumption, the batteries of some known flow sensing devices may need to be replaced and / or recharged at least once a year, which is expensive and cumbersome

Images