Evaporative cooling examples

Open steady-flow systems, which include almost all air conditioning processes, foUow this law. Examples include the energy flows in a cooling and dehurnidifying coil or an evaporative cooling system. 

Example 4 Evaporative Cooling Air at 95 F dry-bulb temperature and 70 F wet-bulb temperature contacts a water spray, where its relative humidity is increased to 90 percent. The spray water is recirculated makeup water enters at 70 F. Determine exit dry-bulb temperature, wet-bulb temperature, change in enthalpy of the air, and quantity of moisture added per pound of dry air. 

Example 2 Yield from Evaporative Cooling Starting with 1000 lb of water in a solution at H on the solubility diagram in Fig. 18-57, calculate the yield on evaporative cooling and concentrate the solution back to point H so the cycle can be repeated, indicating the amount of NaCl precipitated and the evaporation and dilution required at the different steps in the process. 

This hypothesis has been somewhat controversial. For example, evaporative cooling of the ocean surface (Fu et al., 1992) and large-scale dynamical feedbacks (Wallace, 1992) have also been suggested as being important in the feedback, suggesting that changes in cloud cover reflect changes in atmospheric circulation... 

This book is primarily concerned with the water treatment of evaporative cooling systems (see the schematic examples shown in Figures 1.1 and 1.2)... 

If a runaway is detected at such an early stage, a controlled depressurization of the reactor may be considered. As an example, during an amination reaction, a 4 m3 reactor could be cooled from 200 °C to 100 °C within 10 minutes without external cooling, just by using a controlled depressurization allowing evaporative cooling. Obviously, the scrubber and the reflux condenser must be designed to work with independent utilities. 

Initial adjustment period—is the stage at which the wet feed material heats up or cools down to the starting drying temperature which is basically referred to as the wet cake temperature. For example, the wet feed is introduced to the heated dryer at ambient temperature. During this period the material temperature will start to rise to the wet bulb temperature which may be different from the initial feed temperature. The reason the temperature of the wet cake remains low relative to the gas temperature is a phenomenon known as evaporative cooling. 

The temperature of the battery depends on the outside air temperature and the operation parameters. Therefore, in Keu of thermal management, the battery temperature cannot be below the ambient temperature. If battery temperatures below the ambient temperature are necessary, the incoming air must be cooled. This can be done with an evaporator, for example. In the case of very low ambient temperatures, it is also possible to heat the incoming air. 

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