Determination of the Relative Humidity of the TTQC lab by using wet & dry bulb hygrometer

Introduction: We know that,

                       Relative humidity = (Actual vapour pressure/ Saturated vapour pressure)×100%

 Th Actual vapour pressure ratio to standard vapour ratio pressure ratio at the same temperature defines as the percentange is called relative humidity percentange.

Object:

• To maintain atmospheric condition of testing laboratory
• To obtain good efficiency in work place
• To know wet and dry bulb hygrometer
• To relative humidity is used to maintain physical properties of the fibre

Working principle:    If the bulb of thermometer is surrounded is not saturated, water evaporates from the bulb into the air at a rate which is proportional to the difference between the actual humidity since the evaporates is accompanied by cooling the temperature indicated by the thermometer will be less than room temperature.

Machine description: This system contain two thermometer, one is dry and other is comp connected, with wet steeve of muslin Distilled water stronged in this small boy which is used to contain a chart by which and half of the difference of dry and wet bulb temperature. We determined the temperature.

Apparatus:

1. Two thermo meter (dry and wet)
2. Hanger
3. Muslin
4. Distilled water
5. Water
6. 0°c scale and °F scale
7. Chart for relative humidity

dry and wet bulb hygrometer

Working procedure:

1. At first we took wet bulb reading.
2. Then we have to calculate the difference.
3. We took reading of wet bulb and dry bulb 5 times at a internal of 15 minute.
4. After getting 5 reading we calculate the average of RH% 

Calculation:

     1^St reading,

            Dry bulb temperature =27°C

            Wet bulb temperature =23°C

            Difference =(27-23)°C

                              = 4°c

Similarity 2^nd , 3^rd , 4^th , 5^th  difference 4°C, 3°C, 3°C, 1°C

Average = {(70%+69%+76%+77%+92%)÷5)}=76.8%

Table: For dry bulb and weft bulb

Obser vation	time	Dry bulb temperature	Wet bulb temp	difference	RH	Avg RH
1	2.05	27	23	4	70	76.8
2	2.35	26	22	4	69
3	3.10	28	25	3	76
4	3.45	27	24	3	77
5	4.30	26	25	1	92

Result:  The average RH is 76.8%

Remarks: this one is an experiment dry and wet bulb hygrometer is way to determined quicker determination effect not eligible for testing laboratory.