1. Learning Psychrometrics and Sensors measuring T and RH 方煒 台大生機系教授 Wei Fang, Ph.D., Professor Dept. of Bio-Industrial Mechatronics Engineering, National Taiwan University

2. Analog Dry Bulb Temperature sensor

3. Analog Dry and Wet Bulb Temperature

4. Digital Dry Bulb Temperature reader

5. Infra-red Dry Bulb Temperature

6. Sensing element

7. Dry and wet Bulb Temperature sensors in Weather station and greenhouse

8. T db and RH Sensors

9. T db and RH data logger

10. Day/Night trends of T and RH

11. High T coexist with Low Hum. 午夜 中午 午夜 溫度 濕度

12. High humid Env. Low T, High RHHigh T, Low RH

13. Forced ventilation

14. Evaporative cooling Fogging

15. Evaporative cooling Pad and Fan system

16. Approach to release thermal stress

17. Beware of the side effect.

18. Psychrometric Chart

21. Process: from one state to another

24. Human comfort zone

25. Animal comfort zone – T only Dry bulb temperature Productivity

26. Impact of T and RH on milk production of cows THI>85, no recovery Adapted from ASHRAE Fundamentals, 1999 75.7379.9663.765.05 72.32 68.4763.39 76.68 90.09 87.09 88.06 64.31 64.6582.49 86.01 82.09 82.36 84.21

27. Reduction of milk vs. Temperature-Humidity Index (THI) Adapted from ASHRAE Fundamentals, 1999

28. Milk Production=f(HD74, HA80S) MP = 21.48 – 0.051 * HD74 – 0.0099 * HA80S Where, –MP: Milk production (in kg/day/cow ) –21.48: daily production (in kg) per cow in normal weather condition –HD74: total hrs of THI > 74 for previous 4 days –HA80S: square of total hrs of THI > 80 for previous day Linvill and Pardue (1992)

29. THI lines on Psychrometric chart

30. More about Psychrometric chart Following contents, created by the author, are available from DSpace at UVM. Tutorial for digital psy chart Digital psychrometric chart software

31. The End