Version 3 of Rectangular Radio Antenna and etcl Slot Calculator Demo Example

Rectangular Radio Antenna and eTCL Slot Calculator Demo Example

This page is under development. Comments are welcome, but please load any comments in the comments section at the bottom of the page. Please include your wiki MONIKER in your comment with the same courtesy that I will give you. Its very hard to reply intelligibly without some background of the correspondent. Thanks,gold

• Rectangular Radio Antenna and eTCL Slot Calculator Demo Example
  • Testcases Section
    • Testcase 1
    • Testcase 4
    • Rating small gas stoves boiling water
    • Testcase 5
    • Rating kilns
    • Testcase 5
  • Screenshots Section
    • figure 1.
    • figure 2.
    • figure 3.
    • figure 4.
    • figure 5.
  • References:
• Appendix Code
  • appendix TCL programs and scripts
  • Pushbutton Operation
  • Initial Console Program
• Comments Section

gold Here is some eTCL starter code for calculating efficiency of heat engines from source temperature, fuel, and combustion chamber dimensions. The Novikov efficiency rating can be compared with a process fraction of useful work in an eTCL calculator, developed from some code on a firebox. The impetus for these calculations was checking rated efficiency in some heat engines. Most of the testcases involve modeled data, using assumptions and rules of thumb .

Testcases Section

In planning any software, it is advisable to gather a number of testcases to check the results of the program. The math for the testcases can be checked by pasting statements in the TCL console. Aside from the TCL calculator display, when one presses the report button on the calculator, one will have console show access to the capacity functions (subroutines).

Testcase 1

Pizza is baked for 20 minutes

    namespace path {::tcl::mathop ::tcl::mathfunc}
    set Nu_Carnot  [ - 1.  [/ 300. 900. ] ]
    set Nu_Carnot  [ - 1.  [/ 300. 1200. ] ]

Testcase 4

Rating small gas stoves boiling water

    set Nu_Carnot  [ - 1.  [/ 32. 96.5 ] ]
    set Nu_Carnot  [ - 1.  [/ 24.5 95.5 ] ]
    set Nu_Carnot  [ - 1.  [/ 24. 96.5 ] ]
    set Nu_Novikov  [ - 1.  [sqrt [/ 32. 96.5 ] ]]
    set Nu_Novikov  [ - 1.  [sqrt [/ 24.5 95.5 ] ]]
    set Nu_Novikov  [ - 1.  [sqrt [/ 24.5 96.5 ] ]]

Testcase 5

Rating kilns

#Not sure formulas work on kilns?

    set Nu_Carnot  [ - 1.  [/ 300. 1370. ] ]
    set Nu_Carnot  [ - 1.  [/ 300. 1400. ] ]
    set Nu_Novikov  [ - 1.  [sqrt [/ 300. 1370. ] ]]
    set Nu_Novikov  [ - 1.  [sqrt [/ 300. 1400. ] ]]

Testcase 5

The fuel used was wood at 237 kg in 135 min or 135*60 or 8100 seconds. The average heat flux was 237*16 MJ/kg over 8100 seconds, 237*16/8100, or 0.468 MJ/S. A WATT is a joule per second, so the heat power is 0.468 E6 J/S, or 4.68E5 watts.Using electrical analog model, Q in watts equals (TH-TL)/(R1+R2+R3+R4) or (TH-TL)/(SUM of R) , where TH=1200 deg K and TL=300 deg K. From the eTCL calculator, Nu(1200,300)returns Carnot Nu 0.75 and Novikov Nu 0.5. The thermaI current is estimated as I=4.68E5 watts Many statements below can be pasted into eTCL console window.

 set current   4.5E5 
 R=    delta T/ power or(1200K-300K)        /4.68E5 watts  
 delta 1200K-300K = 900K (SUM of delta T’s of each R)
 set R_overall [/   900 4.65e5]
  SUM R =0.00190 OR 1.9e-3
 R2 is largest component of SUM R
 For each R step,    R=    delta T/ power
 R1 is  delta 100K / 4.5E5 =0.000222
 R2 is  delta 700K / 4.5E5 =0.001555
 R3 is  delta 50K / 4.5E5 =0.0001111 
 R4 is  delta 50K / 4.5E5 =0.0001111
 2% set R1 [/  100 4.5E5]
 0.000222
 3% set R2 [/  700 4.5E5]
 0.001555
 4% set R3 [/  50 4.5E5]
 0.001111
 5% set R4 [/  50 4.5E5]
 0.001111
 6% set sumR [+ 0.000222 0.001555 0.000111  0.000111 ]
 0.00199
 P=VOLTS*CURRENT>> (T1-T2)*I
 set R2_power [* [- 800 100] 500]
 350000
 set efficiency [/ 3.5E5 4.5E5 ]
 0.77777
 set process_heat [/  [* [- 100 50] 500] 4.5E5 ]
 0.0555 or 5.55 percent.
 Only small portion of heat cooks pizza

Screenshots Section

figure 1.

figure 2.

figure 3.

figure 4.

figure 5.

References:

• Kenyan Ceramic Jiko cooking stove, by Hugh Allen
• Endoreversible Thermodynamics, Katharina Wagner,

Appendix Code

appendix TCL programs and scripts

        pack .calculator  -in .buttons -side top -padx 10 -pady 5
        pack  .clearallx .cons .about .exit .test4 .test3 .test2   -side bottom -in .buttons
        grid .frame .buttons -sticky ns -pady {0 10}
        . configure -background aquamarine4 -highlightcolor brown -relief raised -border 30
        wm title . "Heat Engine Combustion Calculator "       

Pushbutton Operation

For the push buttons, the recommended procedure is push testcase and fill frame, change first three entries etc, push solve, and then push report. Report allows copy and paste from console, but takes away from computer "efficiency". While the testcases are in meters, the units either cancel out or are carried through in the calculator equations. So the units could be entered as English feet, Egyptian royal cubits, Sumerian gars, or Chinese inches and the outputs of volume will in the same (cubic) units. This is an advantage since the units in the ancient Sumerian, Indian, and Chinese texts are open to question. In some benign quarters of the globe, feet and cubic feet were still being used for design in the 1970's.

For testcases in a computer session, the eTCL calculator increments a new testcase number internally, eg. TC(1), TC(2) , TC(3) , TC(N). The testcase number is internal to the calculator and will not be printed until the report button is pushed for the current result numbers (which numbers will be cleared on the next solve button.) The command { calculate; reportx } or { calculate ; reportx; clearx } can be added or changed to report automatically, but is not recommended as computer efficiency is impaired. Another wrinkle would be to print out the current text, delimiters, and numbers in a TCL wiki style table as

  puts " %| testcase $testcase_number | value| units |comment |%"
  puts " &| volume| $volume| cubic meters |based on length $side1 and width $side2   |&"  

Initial Console Program

        # pretty print from autoindent and ased editor
        # Novikov efficiency of small gas stoves
        # written on Windows XP on eTCL
        # working under TCL version 8.5.6 and eTCL 1.0.1
        # gold on TCL WIKI , 8aug2013
       

Comments Section