Jurnal Dinamika Vokasional Teknik Mesin Vol.
No.
April 2023, pp.
https://journal.
id/index.
php/dynamika/issue/view/53747 ISSN: 2548-7590.
DOI: 10.
21831/dinamika.
Analysis effect of wall dimensions on thermal resistance in furnace induction 1200 AC Ahmad Zohari 1*.
Eka Bima Saputra2.
Rivaldo3.
Sigit Ariyanto4.
Andriansyah5 1234Mechanical Engineering.
Gajah Tunggal Polytechnic Jl.
Gajah Tunggal No.
Tangerang 15133.
Indonesia 1corresponding author: zohari2980@gmail.
Article Info
ABSTRACT
Article history:
The development of the metal hardening industry using electrical induction to increase the hardening temperature chamber is rapid.
The temperature can reach 1200 AC quickly by adjusting the electricity input to the heater.
However, the temperature can also decrease significantly if the thermal resistance of the room cannot prevent heat transfer outside.
The research method uses analysis of other research and direct measurements on induction furnace machines.
The machine specifications have maximum room temperature (T1= 1200 EE), surrounding temperature (T2= 25.
8 AC), and firebrick thermal conductivity .
= 4.
78 J/s mAC).
Researchers focused on testing variations of wall dimensions .
readth and thicknes.
Based on calculation results, the best thermal resistance is 1.
1308 in dimension 2 with a breadth of 259 cm2 and thickness of 14 cm.
This is in accordance with the theory of thermal resistance that the higher thermal resistance produced, the higher the material's ability to inhibit the rate of heat flow.
Received October 10, 2022 Revised March 25, 2023 Accepted April 30, 2023 Published April 30, 2023 Keywords:
Metal Hardening Induction Thermal resistance Dimension Corresponding Author:
Ahmad Zohari Department of Mechanical Engineering Politeknik Gadjah Tunggal St.
Gajah Tunggal 16.
Tangerang 15133.
Indonesia Email: zohari2980@gmail.
INTRODUCTION
A furnace is defined as a tool capable of providing heat treatment of materials and making other forms of its microstructure and properties (Suprastiyo & Harmi Tjahjanti, 2.
The use of furnaces has an important role in the world of research with the heat treatment of materials formed from the working process of each element in the furnace and transferred to the material to be heated.
The heat transfer process is commonly known as the heat transfer process, which occurs due to a temperature difference in the system causing heat transfer.
The fast heat transfer rate from inside the hardening chamber to outside the wall will cause the hardening temperature to drop.
The temperature of the hardening room causes this, the temperature of the surrounding environment, the thermal conductivity of the material making up the walls, and the considerable thermal resistance.
The tropics' standard temperature or ambient temperature is around 8 Ae 27.
1 AC (Budi et al.
, 2.
In the wall-building materials .
ement and refractory ston.
, a heat Jurnal Dinamika Vokasional Teknik Mesin.
Volume.
8 No.
April 2023 | 22 transfer process will occur by conduction, which has thermal conductivity and thermal resistance.
this case, the researcher refers to other studies that have been conducted previously regarding the measurement of thermal conductivity of composites .
mixture of cement and refractory ston.
and obtained a thermal conductivity value of 4.
78 J/s mAC (Wardhani & Rahardjo, 2.
The next factor to be reviewed is thermal resistance in the hardening chamber.
The material's thermal resistance is used to reduce the heat transfer rate due to the temperature difference on the inside and outside of the room (Ajiwiguna et al.
, 2.
The Area of the wall material and the distance between the inner and outer sides or the thickness of the wall can affect the amount of thermal resistance.
Therefore, it is very important to carry out an analysis or study of the influence of the dimensions (Area and thicknes.
of the room in order to determine the thermal resistance that exists on the furnace wall.
Figure 1.
Furnace Machine Chamber
METHOD
The mechanism of the process of heat transfer or heat transfer occurs by conduction.
This means the heat transfer process involves thermal conductivity in the test analysis.
Thus, thermal conductivity is the ability of a material to absorb heat in each unit of time, material length, and temperature.
The thermal conductivity values for the materials that make up the walls of the hardening chamber were obtained from other researchers who had previously conducted tests on cement and refractory stone in furnaces (Wright et al.
, 2003.
Wardhani & Rahardjo, 2015.
Pramesti & Akbar, 2.
Thus, in this study, an analysis will be carried out regarding the influence of the dimensions of the walls (Area and thicknes.
on the value of thermal resistance that occurs in the induction furnace to reduce the heat transfer rate.
Researchers reviewed some data from references before analyzing the thermal resistance on the wall dimensions of the 1200 EE induction furnace machine.
Not only looking for references, but Jurnal Dinamika Vokasional Teknik Mesin.
Volume.
8 No.
April 2023 | 23 researchers also made direct measurements on a 1200 EE induction furnace machine made by the Gajah Tunggal Polytechnic Team.
The data collection results are in the form of variations in dimensional measurement data (Area and thicknes.
of the walls of the 1200 EE induction furnace machine.
The following are the dimensions of the room which will be shown in Table 1.
Tabel 1.
Dimension Variation Num.
Inside Dimensions .
20 x 20 15 x 15 22 x 22 19 x 19 21 x 21 Outside Dimension .
32 x 32 22 x 22 27 x 27 25 x 25 28 x 28 Thick .
The following dimensional data is a variation of the dimensions of the furnace room, which will later be used to make an induction furnace with a temperature of 1200 AC.
The research will focus on calculating the wall material's thermal resistance.
Heat transfer occurs through conduction with an intermediary object .
(Wardhani & Rahardjo, 2.
The equation used in calculating the value of the thermal resistance to the displacement rate is as follows (Holman, 2008.
Incropera et al.
, 2.
If heat is analogous to electricity, it will be:
ycN OeycN ycyco = 2OIycu 1 ycoya The relationship between thermal resistance and heat has an inversely proportional value:
ycIycEa = OIT If the different temperatures are translated, then:
ycN OeycN ycIycEa = 2yc 1 yco Information:
ycyco = heat = Outdoor Temperature = conductivity ycN2 = Heater Temperature = Cross-sectional Area OIycu = Room Thickness Rth = Thermal Resistance The data collection method based on several references produced data in the form of conductivity values .
= 4.
78 J/s m AC), ambient temperature .
cN1 = 25.
8 AC), and hardening room temperature .
cN2 = 1200 AC).
These data will be used in calculating the thermal resistance value of the induction furnace in the 1200 EE hardening temperature.
The flow of activities carried out in this study is as follows:
Library Studies The first stage is the study of literature in which a search for references related to the existing process of the induction furnace.
Jurnal Dinamika Vokasional Teknik Mesin.
Volume.
8 No.
April 2023 | 24 The calculation for Heat Flow In the second stage, a calculation process is carried out on each wall dimension variation data in the form of area and wall thickness of the induction furnace thickness.
Next, calculate the amount of heat based on the wall area.
Thermal Resistance Value The third stage is used to obtain the value of thermal resistance on various wall dimensions using the heat that has been searched for.
Get the dimension with the Best Barriers After calculating the value of the thermal resistance in each dimension, researchers can find out the dimensions (Area and thicknes.
of the wall that will be used as a reference in making an induction furnace so that it will get optimal heat.
RESULTS AND DISCUSSION
The following results in calculating the thermal resistance value for each dimension of the induction furnace wall.
Calculation of first-dimensional variation The resistance value in the first dimension can be seen in Table 2.
The heat flow value is given ycyco = ycN2 Oe ycN1 ycoya OIycu ycyco = .
0Oe25,.
EE 24 ycayco ya .
,78 yc ycoEE ycu 624 ycayco.
ya yc ycyco = 1.
400,92 EE yco2 EE Furthermore, the thermal resistance value is given by:
ycIycEa = ycIycEa = ycN2 Oe ycN1 ycyco .
0 Oe 25,.
EE ya 400,92 EE yc yco2 EE yc ycIycEa = 0,8382 ya yco2 EE Table 2.
First Dimension Properties Outside Dimension .
Inside Dimension .
Thick .
Total Area .
ya Heat Flow (EE yco2 EE) yc
Resistance Value ( yco2 EE ) ya Value 32 x 32
20 x 20
400,92
0,8382
Jurnal Dinamika Vokasional Teknik Mesin.
Volume.
8 No.
April 2023 | 25 Calculation of second-dimensional variation The resistance value in the second dimension can be seen in Table 3.
Through the same calculation as above, the heat flow is obtained:
ycyco = ycyco = ycN2 Oe ycN1 ycoya OIycu .
0Oe25,.
EE 14 ycayco ya .
,78 yc ycoEE ycu 259 ycayco2 ) ya ycyco = 1.
038,34EE yc yco2 EE Then the thermal resistance value is:
ycIycEa = ycIycEa = ycN2 Oe ycN1 ycyco .
0 Oe 25,.
EE ya 038,34 EE yc yco2 EE yc ycIycEa = 1,1308 ya yco2 EE Table 3.
Second Dimensi Properties Outside Dimension .
Inside Dimension .
Thick .
Total Area .
ya Heat Flow (EE yco2 EE) yc
Resistance Value ( yco2 EE ) ya Value 22 x 22
15 x 15
038,34
1,1308
Calculation third dimension variations The resistance value in the third dimension can be seen in Table 4.
The heat flow value is ycyco = ycyco = ycN2 Oe ycN1 ycoya OIycu .
0Oe25,.
EE 10 ycayco ya yc .
,78 ycoEE ycu 245 ycayco2 ) ya ycyco = 1.
375,11EE yc yco2 EE The thermal resistance value is:
ycIycEa = ycIycEa = ycN2 Oe ycN1 ycyco .
0 Oe 25,.
EE ya 375,11 EE yc yco2 EE yc ycIycEa = 0,8539 ya yco2 EE Jurnal Dinamika Vokasional Teknik Mesin.
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April 2023 | 26 Table 4.
Third Dimension Properties Outside Dimension .
Inside Dimension .
Thick .
Total Area .
ya Heat Flow (EE yco2 EE) yc
Resistance Value ( yco2 EE ) ya Value 27 x 27
22 x 22
375,11
0,8539
Calculation of fourth-dimension variations The resistance value in the fourth dimension can be seen in Table 5.
The heat flow value is:
ycyco = ycyco = ycN2 Oe ycN1 ycoya OIycu .
0Oe25,.
EE 12 ycayco ya .
,78 yc ycoEE ycu 264 ycayco2 ) ya ycyco = 1.
234,78 EE yc yco2 EE The thermal resistance value is:
ycIycEa = ycIycEa = ycN2 Oe ycN1 ycyco .
0 Oe 25,.
EE ya 234,78 EE yc yco2 EE ycIycEa = 0,9509 yc ya yco2 EE Table 5.
Fourth Dimension Properties Outside Dimension .
Inside Dimension .
Thick .
Total Area .
ya Heat Flow (EE yco2 EE) yc
Resistance Value ( yco2 EE ) Value 25 x 25
19 x 19
234,78
0,9509
ya Calculation of fifth-dimension variations The resistance value in the fifth dimension can be seen in Table 6.
The heat flow value is:
ycyco = ycyco = ycN2 Oe ycN1 ycoya OIycu .
0Oe25,.
EE 14 ycayco ya .
,78 yc ycoEE ycu 343ycayco2 ) ya yc ycyco = 1.
375,11 EE yco2 EE The thermal resistance value is:
ycIycEa = ycN2 Oe ycN1 ycyco Jurnal Dinamika Vokasional Teknik Mesin.
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April 2023 | 27 ycIycEa = .
0 Oe 25,.
EE ya 375,11 EE yc yco2 EE ycIycEa = 0,8539 yc 2 yco EE ya Table 6.
Fifth Dimension Properties Outside Dimension .
Inside Dimension .
Thick .
Total Area .
ya Heat Flow (EE yco2 EE) yc
Resistance Value ( yco2 EE ) Value 28 x 28
22 x 22
375,11
0,8539
ya The results of calculating thermal resistance are presented in Table 7.
Table 7.
Results of calculating thermal resistance yc Wall dimension Wide .
Thick .
Thermal resistance ( yco2 EE ) 0,8382 1,1308 0,8539 0,9509 0,8539 ya In Figure 2, it shows the comparison between the dimensional area and the thermal resistance.
The same phenomenon occurs on the comparison between the wall thickness and the thermal resistance, that shows in Figure 3.
The highest value is in the second dimension of 1.
1308 and the lowest value is in the first dimension of 0.
Dimension 1 Dimension 2 Dimension 3 Dimension 4 Dimension Area .
Thermal Resistance Figure 2.
Wide vs.
Thermal Resistance Jurnal Dinamika Vokasional Teknik Mesin.
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April 2023 | 28 Dimension 1 Dimension 2 Dimension 3 Dimension 4 Dimension Thick .
Thermal Resistance Figure 3.
Thick vs.
Thermal Resistance The thermal resistance value obtained has a value that is inversely proportional to the value of the heat flow rate.
The second dimension has a heat flow rate value of 1,038.
34, while the heat flow rate value in the first dimension is 1,400.
This is consistent with research on the thermal resistance theory conducted by (Holman, 2008.
Ajiwiguna et al.
, 2.
, based on this statement stated that the higher the value of the thermal resistance, the higher the ability of the material to inhibit the rate of heat flow.
CONCLUSION
Based on the calculation results, the thermal resistance value was carried out for each variation in the dimensions of the induction furnace, which has specifications for maximum room temperature (T1 = 1200 EE) and ambient temperature (T2 = 25.
8 AC), as well as thermal conductivity for refractory stones .
= 4.
78 J/s mAC).
The most optimal thermal resistance value is 1.
1308, which occurs in the second dimension with an outer side of 22 cm x 22 cm, an inner side of 15 cm x 15 cm, a thickness of 14 cm, and a heat flow of 1038.
In contrast, the lowest thermal resistance value is 0.
8382 in the first dimension with an outer side of 32 cm x 32 cm, an inner side of 20 cm x 20 cm, a thickness of 24 cm, and a heat flow of 1,400.
This is to the theory of thermal resistance that the higher the thermal resistance produced, the higher the material's ability to inhibit the rate of heat flow.
In the heat flow, changes can change the convection coefficient, so heat transfer by convection increases, and the thermal resistance becomes low.
REFERENCES