Week 6

2904ENV Principles of Sustainable Design

Tutorial / Workshop 6 – Week 6

Thermal comfort

Aim: To understand thermal comfort indicators and the meaning of PMV (Predicted Mean Vote)

WORKING IN GROUPS OF TWO CONSIDER THE FOLLOWING TWO climatic conditions on the Gold Coast:

•       Summer

•       Winter

Task:

-        Calculate the PMV for the three sample days in summer and winter (Data from table 1)

-        For the sample Day 2 in summer, calculate the air temperature, humidity and air velocity range in which people will be comfortable and PMV will be between -0.5 and 0.5*.  (Table 2)

-        Further discuss how other factors such as activity or clothing can improve the PMV for the studied sample days

* This means that for calculating the air temperature range in which PMV would be between -0.5 and 0.5, we would keep all the figures in the row of the Day 2 in summer the same and only change air temperature in a way that the red dot in the Psychrometric Chart falls in the Blue Zone. We repeat the procedure for humidity and air velocity.

Use CBE Thermal Comfort Tool available at http://comfort.cbe.berkeley.edu/

Get the climatic data from the table 1.

Fill in the blank spaces in Table 1 and Table 2.

Table 1: Climate Data

Summer	Air temperature (oC)	Globe Temperature (oC)	Air speed (m/s)	Humidity (%)	Activity	Clothing	Mean Radiant Temperature (oC)	PMV	Sensation
Day 1	22.8	24.1	0.1	60	Filing, seated	Knee-length skirt, short sleeve shirt, sandals	24.9	-0.13	Neutral
Day 2	30.0	32.0	2.2	85	Standing relaxed	Shorts, short sleeve shirt	38.8	0.82	Slightly Warm
Day 3	38.5	34.0	0.1	80	Sleeping	Shorts, short-sleeve shirt	31.6	2.44	Warm
Winter
Day 1	19.1	24.0	0.3	55	Sleeping	Trousers, short sleeve shirt, socks, shoes	29.5	-4.15	Cold
Day 2	13.2	20.0	0.1	50	Standing relaxed	Trousers, long sleeve shirt	24.1	-1.81	Cool
Day 3	3.8	5.6	5.3	45	Walking 2mph	Jacket, Trousers, long-sleeve shirt	18.7	-3.28	Cold

Table 2:

Comfort condition range in which PMV is between -0.5 and +0.5	Air temperature Range (oC)	Humidity Range (%)	Air Velocity Range (m/s)
Day 2 in Summer	26.8-29.2oC	<70%	3.5-21 m/s