Sheet1
Input Data
Dimensions (m)
Outside Diameter 0.305
Outside Height (including lid) 0.381
Insulation Thickness 0.051
Hotface Thickness 0.006
Vent Hole Diameter 0.057
Thermodynamic Data
Mass of melt (g) 2270.000
Specific Heat Capacity of solid melt metal (J/g C) 0.576
Melting point of melt metal (C) 660.000
Heat of Fusion of melt metal (J/g) 393.000
Specific Heat Capacity of liquid melt metal (J/g C) 0.604
Pouring temperature of melt (C) 749.000
Mass of crucible (g) 454.000
Specific Heat Capacity of crucible (J/g C) 0.380
Mass of plinth (g) 227.000
Specific Heat Capacity of plinth (J/g C) 1.150
Density of Hotface (g/cc) 2.080
Specific Heat Capacity of hotface (J/g C) 1.250
Density of Insulation (g/cc) 0.130
Specific Heat Capacity of insulation (J/g C) 0.850
Burner Data
Fuel Energy Density (J/g) 50600.000
Fuel Flow Rate (g/sec) 0.126
Exhaust Gas Flow Rate CO2 (g/sec) 0.378
Specific Heat Capacity of CO2 (J/g C) 1.350
Exhaust Gas Flow Rate H2O (g/sec) 0.207
Specific Heat Capacity of H2O (J/g C) 1.970
Starting Furnace Temperature (C) 20.000
Ambient Air Temperature (C) 20.000
Insulation Thermal Conductivity (W/m C) 0.030
Emissivity of melt surface 0.900
Exhaust Gas Flow Rate N2 (g/sec) 1.725
Specific Heat Capacity of N2 (J/g C) 1.040
Natural Gas
MAPP Gas
Acetylene
Oil
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Charcoal/Coke
Bituminous Coal
Dry Wood
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Reference Material
Specific Heat Capacities (solid) (J/g C)
Aluminum 0.576
Copper 0.242
Iron 0.383
Lead 0.074
Zinc 0.214
Mullite 1.250
Specific Heat Capacities (liquid) (J/g C)
Aluminum 0.604
Copper 0.258
Iron 0.349
Lead 0.079
Zinc 0.339
Heats of Fusion (J/g)
Aluminum 393
Copper 211
Iron 207
Lead 24
Zinc 110
Density of Refractory Materials (g/cc)
Ceramic wool 0.13
Foam-spaced clay 0.19
Insulating firebrick 0.48
Insulating castable 0.72
Dense fired clay/Dense firebrick 1.52
Dense castable 1.84
Melting Points of Metals (C)
Aluminum 660
Copper 1083
Iron 1538
Lead 328
Zinc 419
Pouring Temperatures of Metals (C)
Aluminum 749
Copper 1200
Iron 1605
Lead 370
Zinc 455
Fuel Energy Densities (J/g)
Propane 50600
Natural Gas 43000
MAPP Gas 48800
Acetylene 50000
Oil 41600
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Charcoal/Coke 28800
Bituminous Coal 31400
Dry Wood 14900
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Intermediate Steps
Power In (J/sec) 6381.22222
Net Energy Input Needed
Insulation ID/Hotface OD (m) 0.2032
Hotface ID (m) 0.1905
Insulation inside height (m) 0.2794
Hotface inside height (m) 0.2731
Insulation annular area (m^2) 0.0405
Insulation cylinder area (m^2) 0.0729
Hotface annular area (m^2) 0.0039
Hotface cylinder area (m^2) 0.0324
Insulation Total Volume (m^3) 0.0187
Hotface Total Volume (m^3) 0.0013
Insulation Total Mass (g) 2435
Hotface Total Mass (g) 2657
Energy Used to heat Hotface (J) 2,421,451
Energy Used to heat Insulation (J) 754,383
Energy Used to heat Plinth (J) 190,305
Energy Used to heat Crucible (J) 125,767
Energy Used to heat Solid Melt (J) 836,813
Energy Used to Melt Metal (J) 892,110
Energy Used to Heat Liquid Melt (J) 122,026
Net energy input for First Melt (J) 5,342,855
Net energy input for Later Melts (J) 1,850,949
Net energy input less Hf 4450745.133
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Conductive Losses
Bore Circumference (m) 0.5982
Inside Cross-section Area (m^2) 0.0285
Vent Hole Cross-section Area (m^2) 0.0026
Inside Surface Area (m^2) 0.2177
Outside Circumference (m) 0.9571
Outside Cross-section Area (m^2) 0.0729
Outside Surface Area (m^2) 0.5079
Average Surface Area (m^2) 0.3628
Average Power Loss (First Melt) (J/sec) 78.1034962
Average Power Loss (Later Melts) (J/sec) 156.206992
Convective Losses
Heat Flow CO2 J/sec C 0.51075
Heat Flow H2O J/sec C 0.40743978
Heat Flow N2 J/sec C 1.794208
Average Temperature From Cold (C) 364.5
Average Temperature From Hot (C) 729
Average Power Loss (First Melt) (J/sec) 988.66899
Average Power Loss (Later Melts) (J/sec) 1977.33798
Radiant Losses
Stefan-Boltzmann constant (J/sec m^2 K^4) 5.67E-008
Average Temperature From Cold (K) 657.5
Temperature From Hot (K) 1022
Average Power Loss (First Melt) (J/sec) 24.4517728
Average Power Loss (Later Melts) (J/sec) 142.735241
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Net Power Input First Melt (Old Way) (J/sec) 5,290
Net Power Input Later Melts (J/sec) 4,105
Time for First Melt (min) 16.8331985
Time for Later Melts (min) 7.51512411
New Time First Melt (min) 17.6616959
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New First Melt Calculations Instantaneous Power Lo
Steps Furnace Intermediate Temps Conductive
Mirror Ambient (C) 20 0 20 0
Mirror Furnace Start (C) 20 0.01 27.29 1.56206992
Mirror Pouring Temp (C) 749 0.02 34.58 3.12413985
0.03 41.87 4.68620977
0.04 49.16 6.24827969
0.05 56.45 7.81034962
Partial Net Energy Input (J) 0.06 63.74 9.37241954
44066.7835 0.07 71.03 10.9344895
0.08 78.32 12.4965594
0.09 85.61 14.0586293
0.1 92.9 15.6206992
0.11 100.19 17.1827692
0.12 107.48 18.7448391
0.13 114.77 20.306909
0.14 122.06 21.8689789
0.15 129.35 23.4310489
0.16 136.64 24.9931188
0.17 143.93 26.5551887
0.18 151.22 28.1172586
0.19 158.51 29.6793285
0.2 165.8 31.2413985
0.21 173.09 32.8034684
0.22 180.38 34.3655383
0.23 187.67 35.9276082
0.24 194.96 37.4896782
0.25 202.25 39.0517481
0.26 209.54 40.613818
0.27 216.83 42.1758879
0.28 224.12 43.7379579
0.29 231.41 45.3000278
0.3 238.7 46.8620977
0.31 245.99 48.4241676
0.32 253.28 49.9862376
0.33 260.57 51.5483075
0.34 267.86 53.1103774
0.35 275.15 54.6724473
0.36 282.44 56.2345173
0.37 289.73 57.7965872
0.38 297.02 59.3586571
0.39 304.31 60.920727
0.4 311.6 62.4827969
0.41 318.89 64.0448669
0.42 326.18 65.6069368
0.43 333.47 67.1690067
0.44 340.76 68.7310766
0.45 348.05 70.2931466
0.46 355.34 71.8552165
0.47 362.63 73.4172864
0.48 369.92 74.9793563
0.49 377.21 76.5414263
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0.5 384.5 78.1034962
0.51 391.79 79.6655661
0.52 399.08 81.227636
0.53 406.37 82.789706
0.54 413.66 84.3517759
0.55 420.95 85.9138458
0.56 428.24 87.4759157
0.57 435.53 89.0379856
0.58 442.82 90.6000556
0.59 450.11 92.1621255
0.6 457.4 93.7241954
0.61 464.69 95.2862653
0.62 471.98 96.8483353
0.63 479.27 98.4104052
0.64 486.56 99.9724751
0.65 493.85 101.534545
0.66 501.14 103.096615
0.67 508.43 104.658685
0.68 515.72 106.220755
0.69 523.01 107.782825
0.7 530.3 109.344895
0.71 537.59 110.906965
0.72 544.88 112.469035
0.73 552.17 114.031104
0.74 559.46 115.593174
0.75 566.75 117.155244
0.76 574.04 118.717314
0.77 581.33 120.279384
0.78 588.62 121.841454
0.79 595.91 123.403524
0.8 603.2 124.965594
0.81 610.49 126.527664
0.82 617.78 128.089734
0.83 625.07 129.651804
0.84 632.36 131.213874
0.85 639.65 132.775944
0.86 646.94 134.338013
0.87 654.23 135.900083
0.88 661.52 137.462153
0.89 668.81 139.024223
0.9 676.1 140.586293
0.91 683.39 142.148363
0.92 690.68 143.710433
0.93 697.97 145.272503
0.94 705.26 146.834573
0.95 712.55 148.396643
0.96 719.84 149.958713
0.97 727.13 151.520783
0.98 734.42 153.082853
0.99 741.71 154.644922
1 749 156.206992
Sum 7888.45311
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Average 78.1034962
Old Values 78.1034962
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Instantaneous Power Loss (J/s) Net Power Input (J/s) Step Time (sec)
Convective Radiant
0 0 6381.222222 6.905696427
19.7733798 0.09960746 6359.787165 6.928971419
39.5467596 0.20673961 6338.344583 6.952412088
59.3201394 0.32176619 6316.894107 6.976020613
79.0935192 0.44506582 6295.435358 6.999799219
98.866899 0.57702597 6273.967948 7.023750179
118.640279 0.71804299 6252.491481 7.047875816
138.413659 0.86852212 6231.005552 7.0721785
158.187038 1.02887742 6209.509747 7.096660653
177.960418 1.19953187 6188.003643 7.12132475
197.733798 1.38091728 6166.486808 7.146173319
217.507178 1.57347434 6144.958801 7.171208941
237.280558 1.77765262 6123.419173 7.196434256
257.053937 1.99391055 6101.867465 7.221851957
276.827317 2.22271542 6080.303211 7.247464801
296.600697 2.46454341 6058.725933 7.2732756
316.374077 2.71987954 6037.135147 7.299287232
336.147457 2.98921772 6015.530359 7.325502635
355.920836 3.27306073 5993.911066 7.351924813
375.694216 3.57192019 5972.276757 7.378556837
395.467596 3.88631663 5950.626911 7.405401843
415.240976 4.21677942 5928.960999 7.432463042
435.014356 4.5638468 5907.278481 7.45974371
454.787735 4.9280659 5885.578813 7.487247202
474.561115 5.30999269 5863.861436 7.514976944
494.334495 5.71019202 5842.125787 7.542936442
514.107875 6.12923761 5820.371292 7.571129278
533.881255 6.56771206 5798.597368 7.599559118
553.654634 7.02620682 5776.803423 7.628229709
573.428014 7.50532221 5754.988858 7.657144885
593.201394 8.00566744 5733.153063 7.686308566
612.974774 8.52786055 5711.29542 7.715724762
632.748154 9.07252849 5689.415303 7.745397577
652.521533 9.64030704 5667.512074 7.775331207
672.294913 10.2318409 5645.585091 7.805529948
692.068293 10.8477836 5623.633698 7.835998193
711.841673 11.4887975 5601.657235 7.86674044
731.615053 12.1555539 5579.655029 7.89776129
751.388432 12.8487329 5557.6264 7.929065455
771.161812 13.5690236 5535.570659 7.960657755
790.935192 14.3171238 5513.487109 7.992543126
810.708572 15.0937404 5491.375043 8.024726621
830.481952 15.8995888 5469.233745 8.057213414
850.255331 16.7353936 5447.062491 8.090008803
870.028711 17.6018881 5424.860546 8.123118211
889.802091 18.4998146 5402.62717 8.156547196
909.575471 19.4299241 5380.361611 8.190301449
929.348851 20.3929766 5358.063109 8.224386799
949.12223 21.389741 5335.730895 8.258809218
968.89561 22.4209948 5313.364191 8.293574826
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988.66899 23.4875248 5290.962211 8.328689894
1008.44237 24.5901262 5268.52416 8.364160846
1028.21575 25.7296035 5246.049233 8.39999427
1047.98913 26.9067698 5223.536617 8.436196916
1067.76251 28.1224471 5200.98549 8.472775704
1087.53589 29.3774663 5178.395021 8.509737731
1107.30927 30.6726673 5155.76437 8.547090272
1127.08265 32.0088986 5133.092689 8.58484079
1146.85603 33.3870177 5110.379121 8.622996936
1166.62941 34.8078911 5087.622797 8.661566561
1186.40279 36.2723939 5064.822845 8.700557719
1206.17617 37.7814104 5041.978379 8.739978673
1225.94955 39.3358334 5019.088506 8.779837902
1245.72293 40.9365649 4996.152325 8.82014411
1265.49631 42.5845156 4973.168924 8.860906229
1285.26969 44.280605 4950.137385 8.902133429
1305.04307 46.0257616 4927.056779 8.943835128
1324.81645 47.8209227 4903.926168 8.986020994
1344.58983 49.6670346 4880.744606 9.028700957
1364.36321 51.5650523 4857.511139 9.071885218
1384.13659 53.5159397 4834.224802 9.115584257
1403.90997 55.5206697 4810.884622 9.159808841
1423.68335 57.5802239 4787.489618 9.204570038
1443.45673 59.6955928 4764.0388 9.24987922
1463.23011 61.8677758 4740.531167 9.295748081
1483.00349 64.0977813 4716.965712 9.342188642
1502.77686 66.3866263 4693.341417 9.389213267
1522.55024 68.735337 4669.657257 9.43683467
1542.32362 71.144948 4645.912196 9.485065933
1562.097 73.6165033 4622.105191 9.533920514
1581.87038 76.1510555 4598.235189 9.583412263
1601.64376 78.7496659 4574.301129 9.633555434
1621.41714 81.413405 4550.30194 9.684364704
1641.19052 84.143352 4526.236543 9.735855181
1660.9639 86.940595 4502.10385 9.788042427
1680.73728 89.8062309 4477.902765 9.840942471
1700.51066 92.7413656 4453.63218 9.894571826
1720.28404 95.7471138 4429.290982 9.948947511
1740.05742 98.824599 4404.878048 10.00408706
1759.8308 101.974954 4380.392243 10.06000857
1779.60418 105.199319 4355.832428 10.11673067
1799.37756 108.498846 4331.197452 10.17427259
1819.15094 111.874692 4306.486156 10.23265416
1838.92432 115.328026 4281.697372 10.29189587
1858.6977 118.860025 4256.829923 10.35201882
1878.47108 122.471874 4231.882624 10.41304483
1898.24446 126.164768 4206.85428 10.47499641
1918.01784 129.939911 4181.743688 10.53789682
1937.79122 133.798513 4156.549636 10.60177006
1957.5646 137.741798 4131.270902 10.66664098
1977.33798 141.770993 4105.906256 10.73253522
99855.568 3969.10843 Total Time (sec) 857.4080547
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988.66899 39.2981033
988.66899 24.4517728
Melt Temp Losses
Melt Energy (J) 892110 Cond Conv
Melt Temp (C) 660 137.136454 1735.93458
Net Power Input (J/s) 4409.974237
Time to Melt (sec) 202.2936988
True Total Time (min) 17.66169589
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ses
Rad
98.1769535
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Input Data (user-friendly)
Miscellaneous
Ambient Air Temperature (C) 20
Furnace Start Temperature (C) 20
Melt surface emissivity 0.9 <<< (The default value here should be left alone if you
Dimensions (inches) INSTRUCTIONS: All the cells in gre
Outside Diameter 12 spreadsheet needs no input other th
Outside Height (including lid) 15 are tables of data for common mate
Insulation Thickness 2 make sure the units are the same. (
Hotface Thickness 0.25 and are listed in the non-user friend
Vent Hole Diameter 2.25 with no corresponding data are liste
Thermodynamic Data A first melt time shorter than the late
Weight of melt (lbs) 5 time, means that the furnace specifi
Weight of crucible (lbs) 1 temperature under any conditions.
Weight of plinth (lbs) 0.5
c solid c liquid
Metal Melted Aluminum 0.576 0.604
Copper 0.242 0.258
Iron 0.383 0.349
Lead 0.074 0.079
Zinc 0.214 0.339
Input Metal Data 0.576 0.604
Density c solid
Refractory Used Ceramic wool 0.13 0.85
Foam-spaced clay 0.19 1.15
Insulating firebrick 0.48 1.15
Insulating castable 0.82 1.00
Dense fired clay/Dense firebrick 1.84 1.15
Dense castable 2.24 1.00
Mullite 2.08 1.25
Input Insulation Data 0.13 0.85
Input Hotface Data 2.08 1.25
Input Plinth Data 0.48 1.15
c solid
Crucible Used Steel 0.383
Fireclay 1.25
Clay/graphite 1.09
Silicon Carbide 1.1
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Input Crucible Data 0.38
Energy Density g CO2/g fuel
Fuel Type Used Natural Gas 43000 2.75
Propane 50600 3
MAPP Gas 48800 3.3
Acetylene 50000 3.38
Oil 41600 3.12
Charcoal/Coke 28800 3.67
Input Fuel Data 50600 3
Fuel Flow Rate (lbs/hr) 1
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Output Data
Time First Melt (min) 17.66169589 Old Time First Melt (min) 16.8331985
Time Later Melts (min) 7.515124112
ue here should be left alone if you don't know what it does.)
STRUCTIONS: All the cells in green are for user input, and the
readsheet needs no input other than that. Above some of the cells
e tables of data for common materials. If external data is needed,
ake sure the units are the same. (Units are generally SI standard,
d are listed in the non-user friendly input data.) Units for the cells
th no corresponding data are listed next to those cells.
first melt time shorter than the later melt times, or any negative melt
me, means that the furnace specified cannot achieve the given pouring
mperature under any conditions.
Hf Melting point Pouring Temp
393 660 749
211 1083 1200
207 1538 1605
24 328 370
110 419 455
393 660 749
Thermal Conductivity
0.03
0.05
0.35
0.6
1.8
1.9
2.5
0.03
2.5
0.35
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g H2O/g fuel g N2/g fuel
2.25 15.05
1.64 13.68
0.9 12.04
0.69 11.58
1.34 13.02
0 10.03
1.64 13.68
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Input Data (mirrored)
Dimensions (m)
Outside Diameter 0.305
Outside Height (including lid) 0.381
Insulation Thickness 0.051
Hotface Thickness 0.006
Vent Hole Diameter 0.057
Thermodynamic Data
Mass of melt (g) 2270
Specific Heat Capacity of solid melt metal (J/g C) 0.576
Melting point of melt metal (C) 660
Heat of Fusion of melt metal (J/g) 393
Specific Heat Capacity of liquid melt metal (J/g C) 0.604
Pouring temperature of melt (C) 749
Mass of crucible (g) 454
Specific Heat Capacity of crucible (J/g C) 0.38
Mass of plinth (g) 227
Specific Heat Capacity of plinth (J/g C) 1.15
Density of Hotface (g/cc) 2.08
Specific Heat Capacity of hotface (J/g C) 1.25
Density of Insulation (g/cc) 0.13
Specific Heat Capacity of insulation (J/g C) 0.85
Burner Data
Fuel Energy Density (J/g) 50600
Fuel Flow Rate (g/sec) 0.12611111
Exhaust Gas Flow Rate CO2 (g/sec) 0.37833333
Specific Heat Capacity of CO2 (J/g C) 1.35
Exhaust Gas Flow Rate H2O (g/sec) 0.20682222
Specific Heat Capacity of H2O (J/g C) 1.97
Starting Furnace Temperature (C) 20
Ambient Air Temperature (C) 20
Insulation Thermal Conductivity (W/m C) 0.03
Emissivity of melt surface 0.9
Exhaust Gas Flow Rate N2 (g/sec) 1.7252
Specific Heat Capacity of N2 (J/g C) 1.04
Page 29