• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.9
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• pp.779-785
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• 2003

The present work proposed a newly developed fluidized bed-type psychrometer that could be applicable to the high temperature and contaminant gases. The psychrometer is a device that test gas passes through the water in a glass bottle as a bubbly flow to obtain the adiabatic saturation temperature. A fluidized bed-type psychrometer was made and its characteristics were compared with the Assmann Psychrometer. The characteristic time was in the order of a hundred seconds, and decreased for the decrease of the mass of water and the increase of the air flow rate. The air flow rate and the insulation of the glass bottle were definitely important in the accurate measurement of the wet bulb temperature. The error in wet bulb temperature became less than 5 percent of the difference of dry and wet bulb temperatures if the air velocity in the glass bottle was greater than 1.5m/s.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.2 no.2
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• pp.137-141
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• 1990

When the relative humidity is measured with an aspirated psychrometer, three factors, which affect the measurement of relative humidity, are atmospheric pressure, the size of wet element and the wind velocity. This paper investigated the effects of the above three factors, and the computer code was developed in order to enhance the accuracy of the relative humidity measurement. As results, it is found that the relative humidity decreases by 6%RH with increasing atmospheric pressure from 650 mbar to 1100 mbar. It is found that the relative humidity drops down when the size of the wet element increases, though the effect of the size of the wet element is not significant. Finally, relative humidity increases with the increasing wind velocity. The difference between the psychrometic table in the present KS and the present results is about 2%RH maximum. As a conclusion, the three factors mentioned above should be considered in order to secure accurate measurement of relative humidity.