Cloud water collectors

Mounting of the cloud water collectors on the aircraft is a critical issue because flow-field effects can easily distort the size distribution of drops. If at all possible, the collector should be mounted on a pylon so that the collector is in the free airstream. Substantially greater efficiencies can be achieved if the collector is mounted with a forward inclination of about 12° to 15° relative to a perpendicular from the aircraft longitudinal centerline. This kind of mounting accounts for the nose-up attitude at which most aircraft fly under cruise conditions and also provides a component of the airstream to drive impacted cloud droplets down the rod into the collection vessel, minimizing losses due to blow-off (28). 

A cloud water collector that separates unactivated (interstitial) particles from cloud droplets by jet impaction of these droplets on inert surfaces (12) provides a sample for chemical analyses. 

In June of 1983, five different types of fog/cloud water collectors were compared under field conditions at Henninger Flats. Collectors designed by AeroVironment(AV), Caltech(CIT), the Desert Research Institute(DRI), Global Geochemistry(GGC), and the State University of New York(SUNY)-Albany were tested against one another. The mass and pH of the samples collected were measured on site while the detailed chemical analyses were performed by an independent laboratory, Rockwell International. Results of the intercomparison study, sponsored the the Coordinating Research Council, showed that the Caltech and DRI collectors performed the best over the broadest range of conditions At low liquid water content (i.e. LWC <... 

The composition of cloud and precipitation water was investigated by Petrenchuk and Drozdova (1966), among others they developed a special cloud water collector that worked at positive as well as at negative temperatures. Their results, obtained over the European parts of the U.S.S.R., are given in Table 28. It can be seen that over clean northern regions the difference between the sum of ions in cloud and precipitation elements is not great. In these areas the concentration of sulfate and nitrate ions is relatively small while the chloride content is great. This situation can be explained by maritime influences. In comparison, sulfate is the... 

Cloud Water and Precipitation Collectors. Several methods have been developed for collecting cloud water samples (24-26). Probably the device most commonly used in warm clouds is the slotted rod collector developed by the Atmospheric Science Research Center at the State University of New York (SUNY) at Albany. Commonly known as the ASRC collector (25), this collector consists of an array of rods constructed from Delrin (a form of nylon). Each rod is hollow and has a slot located at its forward stagnation line. The rod radius determines the collection efficiency as a function of particle size, the rods are sized to collect cloud droplets but not submicrometer aerosol particles, and the 50% cutoff is calculated to be at about 3 xm. 

This paper is a summary of our findings from a four-year study of the chemical composition of fog and cloud water in California. Fog water was sampled at a number of sites with a rotating arm collector, which was developed in our laboratory and collects representative samples. Field investigations in the Los Angeles basin, the San Gabriel Mountains, and the San Joaquin Valley revealed very high ionic... 

Fog droplets (10-50 m diameter) are formed in the water-saturated atmosphere (relative humidity = 100%) by condensation on aerosol particles (see Figure 5.2). The fog droplets absorb gases such as SO2, NH3, HCl, and NO. The water droplets are a favorable milieu for the oxidation of many reductants, above all, of SO2 to H2SO4. The liquid water content of a typical fog is often on the order of 10 liter water per m air. The concentrations of ions in fog droplets are often 10-50 times larger than those of rain (Figure 5.11). Clouds process substantial volumes of air and transfer gas and aerosols over large distances. On the other hand, fog droplets are important collectors of local pollutants in the proximity of the earth s surface. 

Fighting water scarcity also involves figuring out how to produce it from waste water, sea water and even clouds. Desahnation by reverse osmosis, purification by membrane filters, mist collectors in desert environments all of these methods involve the use of plastics, or even the creation of new products. The first fog sensor, 4 m high and 12 m wide, made of a hundred nets or polypropylene panels, was installed in the desert of Chile in 2010. The fine particles of water (0.05 to 0.5 g per m of fog) slide along the nets toward gutters which direct them into tanks. A completely passive process, using neither pumps nor electricity, it can collect 15,0001 of water per day, on average. 

Uses Defoamer for metalworking, textiles, pulp/paper, water treatment, l l cleaners, industrial and mech. dishwash rinse aid for automatic dishwashing and windshield washing lubricant for metalworking flotation collector for deinking and recycling of waste paper Properties Hazen 100 liq. sol. in benzene, ethyl acetate, ethyl Icinol, perchlorethylene, veg. oil, olein sp.gr. 1.017 vise. 388 cps m.p. < 0 C HLB 3 cloud pt. 24 2 C surf. tens. 39.0 dynes/cm pH 6 (1% aq.) nonionic 100 /oact. 

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