One way to express atmospheric vapour is in grams of water per kilogram of air or at sea level roughly grams of water per cubic metre of air. So at a conservative temperature of 25C (77F) air can hold roughly 20 grams of water per cubic metre but for dry air of relative humidty of 25% there would be 5 grams of water per cubic metre of air. Assuming the device can extract 20% of the water (in this case cooling the air to 1C or 34F) you would need to process 1000 cu metres of air to get one litre of water; roughly one US quart. So if we assume a windspeed of 15 m/s (54 km/h or 33 mph) and a 10 square metres (roughly 100 sq ft) area of collection we need just under 7 seconds to get a litre. My estimate of 20% collection is likely VERY high and for much of the Australian dessert 25% RH is pretty high too. Cooling air by 24 C degrees takes a pretty large pressure drop in the vanes... roughly 7%. But all that said even an order of magnitude error would permit a one litre per minute collection rate... of course several order of magnitude errors in my estimates would make that per day pretty quickly...so concievable but seems pretty optimistic to me
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Actually I meant desert not dessert...
One way to express atmospheric vapour is in grams of water per kilogram of air or at sea level roughly grams of water per cubic metre of air. So at a conservative temperature of 25C (77F) air can hold roughly 20 grams of water per cubic metre but for dry air of relative humidty of 25% there would be 5 grams of water per cubic metre of air. Assuming the device can extract 20% of the water (in this case cooling the air to 1C or 34F) you would need to process 1000 cu metres of air to get one litre of water; roughly one US quart. So if we assume a windspeed of 15 m/s (54 km/h or 33 mph) and a 10 square metres (roughly 100 sq ft) area of collection we need just under 7 seconds to get a litre. My estimate of 20% collection is likely VERY high and for much of the Australian dessert 25% RH is pretty high too. Cooling air by 24 C degrees takes a pretty large pressure drop in the vanes... roughly 7%. But all that said even an order of magnitude error would permit a one litre per minute collection rate... of course several order of magnitude errors in my estimates would make that per day pretty quickly...so concievable but seems pretty optimistic to me