Pao hot aerosol generator and Pao cold aerosol generator

Introduction: Pao hot aerosol generator and Pao cold aerosol generator Pao aerosol generator can be divided into two types: thermal generation and cold generation The thermal generator uses the principle of evaporation and condensation to evaporate the aerosol particles being atomized by heater, and then condense them into small droplets under specific conditions After removing the large and small droplets, it leaves about 0.3um mist like Pao into the air duct, with the particle size distribution of 0.1-0.3um Pao leak detection dust source: American aerosol of pao-4 CAS ᦇ 68649-12-7ati emery3004 Pao air-conditioned sol generator is a kind of multi-phase Pao aerosol which uses compressed air to blow bubbles in liquid and splashes through Laskin nozzle The particle size of Zui is about 0.65um Cold Pao is often used when scanning the filter for leakage detection The hot smoke particle size is 0.3 μ m, and the cold smoke particle size is 0.55-0.65 μ M the hot smoke concentration of Pao hot aerosol generator is very large and stable, which is suitable for the leak detection of the filter under the air conditioning unit The cold smoke volume of Pao cold aerosol generator is small and stable, which is suitable for the performance test of a single filter, The smoke of Pao heat generator: tda-5c aerosol is heated to 380-390 ℃ in the instrument, and it needs external nitrogen cylinder (pressure can be adjusted) to blow out under the pressure of compressed air The cold smoke of Pao cold generator: the particles of Pao aerosol occur in condensation vibration TDA-4B compressed gas: 3-9cfm (85-255l / min) 20psi; TDA-6C aerosol generator compressed air (built-in air compressor) Pao cold gas sol generator In other words, the hot aerosol test method can reach a higher upstream concentration of aerosol (PAO) in a shorter period of time, and the upstream concentration is more stable, with better dispersion and higher proportion of submicron particles, so it has better penetrability The disadvantage is that enough dilution and cooling space are needed, otherwise a large part of the aerosol will condense on the filter surface, which may also affect Filter surface performance, so it is better to test the integrity of the filter when the circulating air volume is more than 15000 m3 / h The disadvantage is that the upstream concentration is limited and the aerosol can not reach a higher value The section wind speed has great influence on the integrity test of HEPA, and the larger the wind speed is, the easier it is to be penetrated Relatively speaking, the influence of thermogenic aerosol is more obvious Pao cold gas sol generator The test method is more simple, and the test can be carried out only by controlling the pressure of compressed air source to be stable Moreover, after reaching the upstream concentration value, the test value of HEPA installed in level II biosafety cabinet is stable The change of upstream concentration value causes little change in the test value, and because there is no air condensation process in the cold gas sol, there will be no condensation on the filter surface Oil like accumulation residue is suitable for filter integrity test in small circulating air volume and small space.