A kind of calibration method of powder aerosol concentration sensor

Abstract

The invention discloses a calibration method for a medicine powder aerosol concentration sensor. In the cleaning process, water and impurities in a device are removed, so that accurate preparation of medicine powder aerosol is guaranteed; in the preparation process of the medicine powder aerosol, standard-concentration medicine powder aerosol is obtained; a double closed-loop fuzzy control algorithm is used for controlling airflow speed and pressure intensity so that accuracy and stability of airflow speed and pressure intensity adjustment can be guaranteed; in the process of calibrating the sensor, in consideration of influences on performance of the medicine powder aerosol concentration sensor to be calibrated by the medicine powder aerosol concentration, the airflow speed and the pressure intensity, various influence parameters of the medicine powder aerosol concentration sensor are calibrated through a concentration influence calibration test, a flow speed influence calibration test and a pressure intensity influence calibration test. The calibration method for the medicine powder aerosol concentration sensor improves the calibration accuracy and comprehensiveness of the sensor, and can effectively reduce calibration errors of the medicine powder aerosol concentration sensor.

Description

technical field [0001] The invention relates to a concentration sensor calibration method, in particular to a dedicated calibration technology for a drug powder aerosol concentration sensor, which belongs to the technical field of medical instruments. Background technique [0002] Nebulization inhalation therapy uses a medical nebulizer to disperse the drug (solution or powder) into tiny mist or particles, suspend it in the gas, and enter the respiratory tract and lungs for deposition, so as to moisten the respiratory mucosa, reduce inflammation and eliminate phlegm, For the treatment purpose of relieving spasm and relieving asthma, this treatment method can be applied to the treatment of various acute and chronic inflammations of the respiratory tract and the treatment of asthma and other diseases. Huge advantage. In aerosol inhalation therapy, it is usually necessary to change the dosage of the drug at any time as needed and adjust the concentration of the aerosol particl...

AI Technical Summary

Problems solved by technology

Representatively: Chinese invention patent (CN104359724 A) discloses a polydisperse calibration system for airflow unidirectional flow type particle equipment, which mainly includes a zero air generator, a particle generator, a residence chamber and a calibration instrument connected in sequence by a conduit, It can be checked online whether the measurement value of the sampling instrument meets the standard. If the measurement of the instrument is found to be non-standard, it can be re-calibrated according to the polydisperse calibration system of the particle equipment, so as to improve the accuracy of sampling. However, this calibration device needs to be continuously fed. The uniformity and stability of the aerosol concentration are difficult to guarantee, and it is easy to cause waste of experimental materials; Chinese invention patent (CN102590447A) and Chinese invention patent (CN102830047 A) respectively disclose a circulating dust calibration device, wherein the patent (CN102830047 A) discloses a dust generating device for circulating dust, which includes a cavity and an axial fan. There are openings on the top and bottom of the cavity. One end is connected to the opening at the top of the cavity through a circulation pipe, which can realize dust reuse, and the dust environment in the dust generating device is more stable; the patent (CN102590447 A) relates to a calibration method and equipment for a dust measuring instrument, including Dust instrument, self-circulating pipeline, dust generating device, flow measuring device, flow rate and pressure regulating valve, circulating fan, air filter, air heater, switching valve, dust collector, exhaust fan and connecting pipes between various equipment, etc. After the weighed test dust is dispersed, it is sent into a self-circulation system with a stable gas flow rate, thereby producing a standard dust-containing gas with a flowing and stable concentration, so that the calibrated dust meter can be calibrated quickly and accurately; patent (CN201622229 U) discloses a comprehensive calibration test bench for dust detection transmitter, which consists of a dust density proportioning unit, a dust detection transmitter receiving unit, a dust density detection unit, a dust detection transmitter emission unit, a temperature heating unit, The observation window and the sensor installation unit, the output interface unit of the high-speed high-pressure fan, the high-speed high-pressure fan, the input interface unit of the high-speed high-pressure fan, the test bench frame, etc., adopt the specified dust ratio in the closed-loop pipeline of the standard volume to simulate the dust in the atmosphere Dust density status, used to test the output data of the dust detection transmitter under different dust density conditions, as well as data such as sensitivity, accuracy and reliability

[0004] Regarding the working principle of medical nebulizers, the calibration devices introduced in the above three patents have common problems: (1) The air flow rate and pressure stability in the calibration device are poor, and dust deposition is prone to occur, causing great errors in the calibration results; (2) The medical powder aerosol output by the medical nebulizer has the characteristics of low flow rate and low concentration. In order to ensure the uniform flow of the aerosol, the calibration device in the above three patents has a relatively high wind speed in the air circulation channel, and the wind speed is set to a small value. It is easy to cause the sedimentation of particles under the action of gravity, and there are obvious limitations in the uniformity, persistence, and low-speed internal circulation of the drug powder aerosol in the pipeline, which is not conducive to the repeatability and reliability of sensor calibration; (3) No consideration And it is difficult to measure the influence of pressure and flow rate changes on the output signal of the powder aerosol concentration sensor. It does not involve the specific method of sensor calibration and cannot be used for a comprehensive evaluation of sensor performance.

[0005] After comparison and consideration, the existing dust calibration device and the calibration methods involved cannot simulate the aerosol environment in the output pipeline of the medical nebulizer well, and cannot accurately and comprehensively calibrate the aerosol concentration sensor of the drug powder.

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