Principle and design of gas flow meter

Contents

The utility model relates to the field of gas flow measurement, in particular to a gas flow meter.

Background of the Invention

The intelligent liquid turbine flowmeter is a new type of intelligent instrument that integrates a turbine flow sensor and a display and integration, developed using advanced ultra-low power single-chip microcomputer technology. It has obvious advantages such as compact structure, intuitive and clear readings, high reliability, no interference from external power supplies, lightning resistance, and low cost. It first converts the flow velocity into the speed of the turbine, and then converts the speed into an electrical signal proportional to the flow. This flowmeter is used to detect instantaneous flow and total integrated flow. Its output signal is frequency, which is easy to digitize. However, the detection accuracy of the existing intelligent liquid turbine flowmeter is not high and errors are prone to occur.

Summary of the invention

In view of the defects in the prior art, the utility model provides a gas flow meter, which overcomes the deficiencies of the prior art and further improves the detection accuracy.

In order to achieve the above-mentioned purpose, the utility model provides a gas flow meter, including a shell having a fluid channel inside the shell, a vortex generator is provided in the contraction section of the fluid channel, a derotator is fixed in the outlet section of the fluid channel, a temperature detection device is provided on the shell, a pressure detection device and a frequency detection device are provided in the diffusion section of the fluid channel, and the gas flow meter also includes a connecting part, one end of the connecting part is connected to a flow calculator, and the other end of the connecting part is fixed to the shell.

As a preferred embodiment of the present application, the vortex generator is a spiral blade with a fixed angle. Flanges are respectively provided at the inlet section and the outlet section of the fluid channel. The temperature detection device includes a temperature sensor with a Pt100 platinum resistor as a temperature sensitive element, and the signal output end of the temperature sensor is connected to the signal input end of the flow calculator.

The pressure detection device includes a pressure sensor with a piezoresistive diffused silicon bridge as a sensitive element, and the signal output end of the pressure sensor is connected to the signal input end of the flow calculator. The frequency detection device includes a piezoelectric crystal sensor, and the crystal sensor is arranged at the throat of the diffusion section of the fluid channel. The gas flow meter includes an amplifier, an A/D converter, a preamplifier, a microprocessor and a liquid crystal display; the signal output ends of the temperature sensor and the pressure sensor are connected to the signal input end of the amplifier, the signal output end of the amplifier is connected to the signal input end of the A/D converter, the signal output end of the A/D converter is connected to the signal input end of the microprocessor, the signal output end of the piezoelectric crystal sensor is connected to the signal input end of the preamplifier, the signal output end of the preamplifier is connected to the signal input end of the microprocessor, and the microprocessor is electrically connected to the liquid crystal display.

The beneficial effects of the utility model are: the utility model has no mechanical moving parts, is not easy to corrode, is stable and reliable, has a long service life, and does not require special maintenance for long-term operation; it effectively suppresses interference signals caused by vibration and pressure fluctuations; the intelligent flow meter integrates a flow probe, a microprocessor, a pressure sensor, and a temperature sensor, and adopts a built-in combination to make the structure more compact and improve detection accuracy.