Bubble Extinction Performance And Floating Technology

Foam is a new photo-electricity countermeasure material from the traditional aerosol, it has some advantages with sustained electro-magnetic attenuation effect, environment friendly and using safely, the key of using foam in the photo-electricity countermeasure is the suspension technology.Foam stability plays a crucial role in the time that foam suspend in air. Starting from foam formula research, to choose the foam formula without changing the foamability obviously, mixed experiments were carried out with traditional surfactants in this paper. The function of four kinds of foam stabilizer(gelatin, sodium carboxymethyl cellulose, polyvinyl alcohol and glycerin) was investigated. It can be known that the best formula of foaming is SDS 0.202%, AES 0.119% and polyvinyl alcohol 0.3% in 100 gram water.Also the environment influence on foam such as salt, temperature and pH value on the best formula was studied, conclusion is that the formula is salt-resistant, alkali-resistant, the foam stability is greatly influenced by environment temperature, the best parameter is 20～40℃.Based on the best formula, the effect of foam diameter-distribution, thickness and different ratio to extinction performance of infrared, laser and millimeter wave is characterized by Fourier Transform Inftrared Spectroscopy (FTIR), laser-smoke test instrument and 8mm wave radiation collector. Results indicate that IR transmittance though the foam is under 20% when foam diameter-distribution is 4-7mm and thickness is 10cm, while laser transmittance is under 10%; the average attenuation at 8mm wavelength is 16.7dB when foam diameter-distribution is 0.8-2cm and thickness is 80cm.Based on the research to foam, the suspension principle of foam screen was analyzed in theory, and a simple devise was designed for generating floating foam screen according to the principle. Some technological factors on suspended foam screen is analyzed emphatically. Concluded that when compressed air pressure is 0.4Mpa, gas flow is 0.11L/min, helium pressure is 8MPa, and flow is 7L/min, the foam have nice performance of suspension and duration. At the same time, the extinction performance of foam to infrared, laser and millimeter wave is also characterized, the IR and laser transmittance of the foam is less then 5%, and the attenuation at 8mm wavelength is 2.2 dB. The suspension-foam have a nice prospects for application.