Voltage-and-flow control system used for measurement of aerosol particle size distribution

Abstract

The invention discloses a voltage-and-flow control system used for measurement of aerosol particle size distribution and belongs to the technical field of environment aerosol. The voltage-and-flow control system used for the measurement of the aerosol particle size distribution is structurally characterized in that a circuit board is connected with a high-voltage module, a direct-voltage conversion module, a data acquisition card, an absolute pressure sensor, a mass flow meter and a temperature and humidity sensor through guide wires, the direct-voltage conversion module is connected with a draught fan through a guide wire, an air inlet, a pre-filter, a T-shaped tee joint, the mass flow meter, the draught fan, a flow-limiting hole, a radiating tube, a post-filter and an air outlet are connected in sequence through pipelines, the temperature and humidity sensor is connected with a vertical channel of the T-shaped tee joint through a pipeline, and the absolute pressure sensor is connected with the T-shaped tee joint through a pipeline. The voltage-and-flow control system used for the measurement of the aerosol particle size distribution is simple in operation, high in sensitivity, good in sealing performance, high in running stability, capable of being flexibly assembled with an aerosol particle size distribution measuring instrument, and applied to both laboratory measurement and out-field measurement.

Description

technical field [0001] The invention belongs to the technical field of environmental aerosols, and in particular relates to a voltage and flow control system for measuring aerosol particle size distribution. Background technique [0002] The instrument that uses the method of electric mobility to measure the particle size distribution of aerosol usually needs to provide high pressure and sheath gas to the system to complete the migration of aerosol in the differential electric mobility analyzer (DMA) and screen out different particle sizes of particulate matter. Therefore, the voltage and flow control system is the core component of the aerosol measurement instrument. [0003] At present, aerosol research has attracted more and more attention at home and abroad. my country's newly revised "Ambient Air Quality Standards" also include PM 2.5 This indicator will gradually realize PM across the country. 2.5 monitoring. Most of the existing aerosol particle size distribution...

AI Technical Summary

Problems solved by technology

Existing aerosol particle size distribution measuring instruments mostly use negative high-voltage power supply, which affects the sensitivity of aerosol particle size distribution measurement

Because after the aerosol passes through the bipolar charger, the proportion of negatively charged particles is significantly higher than that of positively charged particles, so a negative high voltage power supply is used to provide DMA to screen positively charged aerosols for measurement, which reduces the sensitivity of the instrument

At the same time, the structure of these instruments is complex, the flexibility is insufficient, and there are inconveniences in the process of disassembly, replacement and multi-system integration.

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