1. TWO-STAGE EVAPORATING COOLER WITH RHCh
The Institute of Power Engineering and Automation of the Academy of Sciences of Republic of Uzbekistan

2. Advantages of evaporating cooler (conditioner)
Reduce of electrical energy consumption by 4-5 times in comparison with compression conditioners
Optimizing of humidity of cooled air
Lack of compressor and increasing of reliability
Simplification of design, reduce of materials consumption and manufacturing content
Low cost (at 3-4 times)
Possibility to combine with alternative electrical sources (particularly, with photovoltaic or thermoelectric generators)

3. Physical basis Evaporation heat of water is 2.4 MJ/kg at 40 °C
Specific heat is 1 kJ/(kg K) for air and 4.8 kJ/(kg K) for water at 40 °C
There is 54.2 g water steam in 1 m3 air at 100 % relative humidity and 40 °C
There is 8.13 g water steam in 1 m3 air at 14 % relative humidity and 40 °C
Decreasing of air temperature as a result of additional water evaporation
Energy consumption for air and water supply only

4. Two-stage evaporative cooler with RHCh (schematic)
1 and 2 are revolving heat changers (RHCh)
3 and 10 are water
4 is atmospheric air
5, 6 and 7 are air flows into RHCh
8 is humid air into atmosphere
9 is air after first RHCh
11 and 12 are cooled air into room

5. Design of evaporative cooler having two RHCh (domestic version)
Without the enclosure
Driver of RHCh and water pump are seen here
Arrows show air flows
With the enclosure
Fans and jalousie for out coming air of first stage are seen here
Power consumption is 50 W,
cooling power is 200 W

6. Photos of the laboratory prototype

7. State of art and prospects
A patent application for a new design of the evaporative cooler of higher efficiency has prepared now.
The design documentation of its version for moderate rooms (20-25 m2) is prepared to conjoint produce with private enterprise “Vershina Olimpa” (Tashkent)
The design documentation of last one for moderate rooms (20-25 m2) and photovoltaic power supply will be prepared in nearest future