patches-own [ heat ] 

to setup 
  ca  
  ask patches [
    set heat  random  212  
    set pcolor  scale-color  red  heat  0  212
  ]
  plot average-heat
end

to boil 
  diffuse  heat  1  
  ask patches [ 
    set heat  (  heat  +  5)  mod  212  ;;warm up patches till they reach 212
    set pcolor  scale-color  red  heat  0  212
  ]
  plot average-heat  
end

to-report average-heat     ;;calculates the average heat
  report sum values-from patches [ heat / ( 4 * screen-edge-x * screen-edge-y ) ] 
end


; *** NetLogo Model Copyright Notice ***
;
; This model was created as part of the project: CONNECTED MATHEMATICS:
; MAKING SENSE OF COMPLEX PHENOMENA THROUGH BUILDING OBJECT-BASED PARALLEL
; MODELS (OBPML).  The project gratefully acknowledges the support of the
; National Science Foundation (Applications of Advanced Technologies
; Program) -- grant numbers RED #9552950 and REC #9632612.
;
; Copyright 1998 by Uri Wilensky. All rights reserved.
;
; Permission to use, modify or redistribute this model is hereby granted,
; provided that both of the following requirements are followed:
; a) this copyright notice is included.
; b) this model will not be redistributed for profit without permission
;    from Uri Wilensky.
; Contact Uri Wilensky for appropriate licenses for redistribution for
; profit.
;
; This model was converted to NetLogo as part of the project:
; PARTICIPATORY SIMULATIONS: NETWORK-BASED DESIGN FOR SYSTEMS LEARNING IN
; CLASSROOMS.  The project gratefully acknowledges the support of the
; National Science Foundation (REPP program) -- grant number REC #9814682.
; Converted from StarLogoT to NetLogo, 2001.  Updated 2002.
;
; To refer to this model in academic publications, please use:
; Wilensky, U. (1998).  NetLogo Boiling model.
; http://ccl.northwestern.edu/netlogo/models/Boiling.
; Center for Connected Learning and Computer-Based Modeling,
; Northwestern University, Evanston, IL.
;
; In other publications, please use:
; Copyright 1998 by Uri Wilensky.  All rights reserved.  See
; http://ccl.northwestern.edu/netlogo/models/Boiling
; for terms of use.
;
; *** End of NetLogo Model Copyright Notice ***
@#$#@#$#@
GRAPHICS-WINDOW
262
10
680
449
25
25
8.0
0
10
1
1
1

CC-WINDOW
2
308
259
449
Command Center

BUTTON
58
51
113
84
setup
setup
NIL
1
T
OBSERVER
T

BUTTON
137
50
192
83
boil
boil
T
1
T
OBSERVER
T

PLOT
9
98
252
294
Average Heat
Time
Avg Heat
0.0
50.0
0.0
250.0
true
false
PENS
"ave-heat" 1.0 0 -65536 true

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WHAT IS IT?
-----------
This project depicts a simple cellular automata model that appears to be like a pot of boiling water. Heat is applied evenly to the entire pot, but when the temperature of a patch reaches the boiling temperature, the bubble pops and that patch's temperature drops to zero.

If all of a cell's neighbors are at the maximum value of 212, then that cell's new value will be 213 which gets wrapped down to zero. At the next tick, the presence of this zero-valued cell will lower the values of the cell's nearest neighbors. This process is analogous to the way in which a hot enough region of water gives up some heat by forming a bubble of steam. The water right around the steam bubble cools off for a moment.


HOW TO USE IT  
-------------
Click the SETUP button to set up a random field of heat. 

Click the BOIL button to start adding heat to the pot and watch it boil. The redder the color, the hotter the patch (Black is very cool and white is very hot).


THINGS TO NOTICE
----------------
Watch how the added heat diffuses through the pot. When bubbles pop, the resulting drop in heat affects nearby patches too by taking away their heat.

What happens to the average heat in the pot?


EXTENDING THE MODEL
-------------------
Try diffusing the heat more slowly through the system.

Change the diffuse parameter from 1 to a smaller fraction.

Add "ice cubes".

Add a heat sink, such as edges that constantly cool the liquid.


CREDITS AND REFERENCES
-----------------------
This model is described on page 79 in  "Artificial Life Lab",  by Rudy Rucker, published in 1993 by Waite Group Press.

To refer to this model in academic publications, please use: Wilensky, U. (1998).  NetLogo Boiling model. http://ccl.northwestern.edu/netlogo/models/Boiling. Center for Connected Learning and Computer-Based Modeling, Northwestern University, Evanston, IL.

In other publications, please use: Copyright 1998 by Uri Wilensky.  All rights reserved.  See http://ccl.northwestern.edu/netlogo/models/Boiling for terms of use.
@#$#@#$#@
default
true
0
Polygon -7566196 true true 150 5 40 250 150 205 260 250

@#$#@#$#@
NetLogo 2.0beta4
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setup
repeat 110 [ boil ]
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