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					Tutorial for Psyc0226
           Wei Fang, Ph.D., Professor
Dept. of Bio-Industrial Mechatronics Engineering
           National Taiwan University

       Software last updated: 2002/02/26
       Tutorial last updated: 2003/11/28
      Capability of Psyc0226
Allow alteration on atmospheric pressure

Provide handy PsyTables
  Totally 11 tables are available

Provide PsyCharts
  State calculation: besides AtmP, values of 2 independent
  states are required to calculate others
  Process calculation: find differences between 2 states
  More process calculation:
     Evaporative cooling
     Vapor pressure deficit on leaf
Abbreviations of thermodynamic properties of
         moist air used in Psyc0226

                 1.    Tdb: dry bulb Temp.
                 2.    RH : relative humidity
                 3.    Twb: Wet bulb Temp.
                 4.    Tdp: dew point Temp.
                 5.    AH : absolute humidity
                 6.    SV : specific volume
                 7.    Hfg: Saturated
                 8.    DOS: degree of Saturation
                 9.    Pws: saturated vapor pressure
                 10.   Pw: vapor pressure

                   More message of the selected cell
Block in red defined as Psychart window
Set the Atmospheric pressure is the
            first step
Handy PsyTables
Totally 11 PsyTables
User friendly 3-step design in PsyTable


                  2. Set the intervals
                      3. List the values

1. Define
the ranges
Table 1: Twb = f(Tdb, RH)



            Twb


  RH (50 – 100%)and Tdb (20 – 44 oC)
Table 2: WBD = f(Tdb,RH)



     WBD

 Wet Bulb Depression is the limit of
   evaporative cooling methods.
Table 3: RH = f(Tdb,Twb)




 RH
Twb (20 – 44 oC) and Tdb (20 – 44 oC)
Table 4: VPD of air
  VPD=Pws@Tdb – Pw@Tdb
AHD=Sat.AH@Tdb – Sat.AH@Tdp




                VPD/AHD of air
Table 5: VPD’ of air
   VPD’=Pw@Twb – Pw@Tdb
AHD’=Sat.AH@Twb – Sat.AH@Tdp




      VPD’/AHD’ of air
                    Psycharts
 Besides atmospheric
 pressure, values of 2    Evaporative cooling
independent states are    process calculation
  required to derive
        others




  find differences           Vapor pressure
  between 2 states           deficit on leaf
State Calculation
     Independent Properties (IP)
    Twb RH    Tdp AH    SV   H    hfg   DOS Pws Pw


Tdb IP   IP   IP   IP   IP   IP         IP     IP




                        Any pair of IP can
                        be the given values
                        to derive others.
One click in Psychart window using left
button of the mouse can define a state
Process Calculation
Use mouse to define 2 states
              1.   To define 2nd state, change
                   from ‘Inactive’ to ‘Active’
                   first.
              2.   Click in the Psychart window
                   at the selected state or click
                   on the crosshair region to
                   move along constant lines or
                   curves.
              3.   Click on ‘Cal.’ to calculate
                   the difference.
Move along prefix lines or Curves
     Constant    Constant   Constant
       Twb         Tdb        RH

  Constant                    Constant
  Tdp, Pw,                    Tdp, Pw,
    AH                          AH

    Constant    Constant    Constant
      RH          Tdb         Twb
A process with sensible heat gain
  Process: between states
Sensible Heating (3->4)
Sensible Cooling (4->3)
Humidification (4->5)
Dehumidification (5->4)
Heating (3->5, 3->1)
Cooling (5->3, 1->3)
Air Mixing (1, 2->3)
Evaporative Cooling,Drying (1->2, 1->3)
Combination of above (1->2->3->4->5)
Evaporative cooling process
   Enter ‘Tdb after pad’ or ‘pad efficiency’ to
derive others followed by a Click on ‘Draw’ icon.




                WBD
        Temperature drop
 after passing through pad (ΔT)
ΔT = WBD of outdoor x Efficiency of the pad




            T                    T- ΔT
     Vapor pressure deficit (VPD)
Enter Leaf temperature,
then click on Draw icon.




                VPD
Other user friendly designs
  Lines and curves can be visible or
hidden by (de)selecting related icons
Zoom in & out
Labels in Psychart window can be hidden
     by de-select the Unit label icon
The state user defined in the psychart window using left
 button of the mouse will be placed in the center of the
  psychart window if the Centralize icon was selected.
          This option is set inactive by default.
Enjoy playing with
    Digital Psychart
Please send us information regarding found bugs.
          Mail to : weifang@ntu.edu.tw