EMPLOYMENT OF PROBABILITYBASED MULTI-RESPONSE OPTIMIZATION IN HIGH VOLTAGE THERMOFLUIDS Текст научной статьи по специальности «Электротехника, электронная техника, информационные технологии»

EMPLOYMENT OF PROBABILITY-BASED MULTI-RESPONSE OPTIMIZATION IN HIGH VOLTAGE THERMOFLUIDS

Joseph Chukwuka Ofodua, Johnson Kehinde Abifarinb

a University of Port Harcourt, Faculty of Engineering, Department of Mechanical Engineering, Choba, Rivers State, Federal Republic of Nigeria, e-mail: rofnelenergy@yahoo.com, ORCID iD: https://orcid.org/0000-0001-8311-7332

b Ahmadu Bello University, Faculty of Engineering, Department of Mechanical Engineering, Zaria, Federal Republic of Nigeria, e-mail: jkabifarin@abu.edu.ng, corresponding author, ORCID iD: https://orcid.org/0000-0003-4930-9132

DOI: 10.5937/vojtehg70-35764; https://doi.org/10.5937/vojtehg70-35764

FIELD: Mechanical engineering, Materials ARTICLE TYPE: Original scientific paper

Abstract:

Introduction/purpose: Researchers of fluids for high voltage engineering application always experience problems when selecting and recommending specific fluids suitable for high voltage application. This is due to the dual functionality of fluids required for high voltage equipment.

Methods: This study introduced and employed a probability-based multi-objective optimization technique in the selection of high voltage thermofluids. Beneficial and unbeneficial preferable probability utility indexes were employed based on the desired properties of oils.

Results: It was shown that the nanofluid with 0.6 wt% A2O3 is the most promising candidate for high voltage equipment compared to other produced fluids considered. It is also noteworthy to state that coconut oil exhibited better performance efficiency compared to standard oil. This study also identifies that the produced Jatropha oil was inadequate for high voltage equipment.

Conclusion: In conclusion, a preliminary study essential for final usage of 0.6 wt% A2O3 nanofluids and coconut oil for high voltage equipment is recommended as well as the improvement of the performance characteristics of Jatropha oil for usage in high voltage equipment.

Keywords: preferable probability optimization, high voltage equipment, thermofluids, physicochemical properties, dielectric strength.

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Introduction

High voltage engineering is an integral area of electrical and mechanical engineering. A lot of devices have been made for high voltage application - power transformers, switchgears, control equipment, communicating devices, and insulators, to mention but a few. The quality of insulating fluids used in such equipment is essential for its wellbeing and efficiency (Oparanti et al, 2020; Oparanti et al, 2022). This study comes with the motivation to apply a novel multi-objective approach in the selection of optimal processing conditions or better performance fluids for high voltage equipment.

Conventional mineral oil has been used in high voltage equipment due to its unique and multifunctional characteristics, which are efficient cooling and dielectric capacity. However, due to mineral oil non-biodegradability and other intricate production tendencies, researchers have worked on the production of alternative fluids for high voltage engineering. Abeysundara et al (2001) produced and examined the properties of coconut oil as an alternative for transformer mineral oil. Sitinjak et al (2003) examined the characteristics of palm oil and its derivative for high voltage equipment. Hosier et al (2009) studied the selection of a suitable vegetable oil for high voltage engineering. Garba et al (2013) produced and characterized Jatropha oil for transformer application. Peppas et al (2016a, 2016b) produced ultrastable natural ester-based nanofluids for high voltage engineering. Oparanti et al (2021a) developed a nanofluid from palm kernel oil for high voltage engineering. Oparanti et al (2021b), in addition to their previous work, analyzed AC breakdown of their synthesized nanofluids from palm kernel oil. In all of these studies, with the ones not mentioned, there has been a challenge in selecting a specific oil sample suitable for high voltage application, considering the dual functionality of a typical high voltage equipment oil. Hence, this study has addressed this challenge by introducing and employing a probability-based optimization technique for multiple performance characteristics of high voltage engineering oil.

Consequently, several techniques such as Ashby's method (Ashby, 2000; Ashby et al, 2004), the TOPSIS method (Deshmukh & Angira, 2019), the grey relational analysis method (Abifarin, 2021; Abifarin et al, 2021a, 2021b, 2021c; Awodi et al, 2021; Abifarin et al, 2022; Abifarin & Ofodu, 2022), and the intersection multi-objective probability method (Wang & Teng, 2021; Zheng, 2022) have been used for multiple objective optimization in several applications; probability-based multi-objective optimization has proven to be simple and more efficient (Zheng, 2022).

Hence, this study selected some data (Abeysundara et al, 2001; Garba et al, 2013; Oparanti et al, 2021a) in high voltage engineering oil development and then the new multi-objective probability optimization technique was employed for the first time to determine the most efficient oil sample among other samples in the study.

Research method

The beneficial utility index method is applied to a desired characteristic which should be as high as possible. The index characteristic indicator contributes positively to a partial preferable probability. Equation 1 is used to compute the partial positive probability index (Pij), while equation 2 is used to compute the normalized factor (a) of the jth utility index of the performance characteristic indicator.

Pij = OCX], i = 1, 2,...,n; j = 1, 2,..m O = 1/(nJ;)

(1) (2)

where Xj is the jth beneficial utility index of the characteristic performance indicator of the ith number of sample, n is the total number of samples considered in the study, m is the total number of utility indices of each sample involved, and Xj is the value of the arithmetic mean of the utility index of the sample characteristic performance indicator. The performance characteristics considered for the beneficial utility index are shown in Table 1:

Table 1 - Beneficial utility high voltage characteristics Таблица 1 - «Чем больше, тем лучше» характеристики изоляционного масла Табела 1- Карактеристике изолационог у^а типа „што више - то бо^е "

Performance characteristics

Beneficial utility discussion

Reference

Activation energy (eV/mol)

The higher the activation energy, the harder it becomes to reduce the viscosity of the liquid at elevated temperature. In other words, a higher activation energy of a fluid leads to a good cooling integrity of the fluid.

(Badicu et al, 2011; Liu et al, 2019; Liu et al, 2020; Oparanti et al 2021a)

Breakdown

voltage/Dielectric strength (kV)

Breakdown voltage or dielectric strength of an insulator is the minimum voltage that makes the portion of an insulator to experience electrical breakdown and become electrically conductive. Also the higher the breakdown voltage of a fluid, the less contaminant the oil. In other words, as high as possible breakdown voltage is required for high voltage equipment.

(Lee et al, 2012; Peppas et al, 2016a, 2016b; Abd-Elhady et al, 2018; Ghoneim et al, 2021; Oparanti et al, 2021a; Asse et al, 2022)

Flash point (oC)

Insulating fluids for high voltage equipment should exhibit a high flash point. This prevents fire outbreak, interrupted power supply and economic loss.

(Kumar et al, 2014; Oparanti et al, 2021a; Oparanti et al, 2022; Minkner & Schmid, 2022)

The unbeneficial utility index method is applied to a desired characteristic which should be as low as possible, i.e. minimization type of optimization is desired. The index characteristic indicator contributes negatively to a partial preferable probability.

Equation 3 is used to compute the partial negative probability index (Pij), while equation 4 is used to compute its normalized factor ($) of the jth utility index of the performance characteristic indicator.

pj

ßij(Xjmax + Xjmin - Xi), i 1, 2,...,n, j 1, 2,

.m

(3)

ßj

j = l/[n(Xjmn + Xjmax) - nX j ]

(4)

Table 2 - Unbeneficial utility high voltage oil characteristics Таблица 2 - «Чем меньше, тем лучше» характеристики изоляционного масла Табела 2 -Карактеристике изолационог у^а типа „што маше - то боъе"

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Performance characteristics Unbeneficial utility discussion Reference

Cloud point The cloud point of an insulating fluid is the temperature at which the fluid begins to condense, i.e. the smaller the cloud point of an insulating fluid, the better it is for high voltage equipment (Garba et al, 2013; Du et al, 2013; Oyelaran et al, 2020)

Viscosity High viscosity of a fluid usually causes poor atomization of the fluid, meaning minimization is required for high voltage equipment (Hosier et al, 2006; Garba et al, 2013; Srinivasa & Surendra, 2019)

Specific gravity Specific gravity is used to examine whether an object will float or sink in water. In other words, if the specific gravity of a fluid is less than one, it means that the fluid will float in water. Lower specific gravity is required to enable the dewatering of the fluid during transformer maintenance. (Gong et al, 2018; Lin et al, 2021)

Density Lower density of a fluid for high voltage equipment is required because it enhances mobility of the fluid. Mobility of the fluid is required for efficient equipment cooling. (Yaacob & Alsaedi, 2015)

Moisture content Moisture content has a negative effect on the insulating and dielectric properties of a transformer oil. No water content or as small as possible water content is desired for high voltage equipment (Ofodu & Abifarin, 2021; Zhang et al, 2021)

Furthermore, the conclusive preferable probability of the analysis is the product of the individual partial preferable probability of a corresponding candidate sample. Afterwards, the ranking is done to show the candidate sample with the best performance characteristics.

Analysis and discussion of the results

Activation energy and breakdown voltage

Oparanti et al (2021a) developed nanofluids and examined their activation energy and breakdown voltage. However, the analysis did not reflect conclusively which oil sample is the best candidate for high voltage equipment. Table 3 shows the oil samples and their corresponding activation energies and breakdown voltages.

Table 3 - Activation energy and breakdown voltage of high voltage fluids

Таблица 3 - Энергия активации и напряжение высоковольтного пробоя

жидкостей

Табела 3 - Активациона енерг^а и напон пуцаша флуида за високонапонску

опрему

Samples Activation energy (eV/mol) Breakdown voltage (kV)

Ester oil 0.04 21

Ester + 0.2 wt% АЬОз 0.09 2з

Ester + 0.4 wt% АЬОз 0.09 27

Ester + 0.6 wt% АЬОз 0.09 29

Ester + 0.8 wt% АЬОз 0.09 29

Ester + 1 wt% АЬОз 0.09 27

Ester + 0.2 wt% ТЮ2 0.047 26

Ester + 0.4wt% ТЮ2 0.047 27

Ester + 0.6 wt% ТЮ2 0.05 28

Ester + 0.8 wt% ТЮ2 0.06 28

Ester + 1 wt% ТЮ2 0.08 28

The data presented in Table 3 was analyzed using the beneficial utility index as the higher-the-better characteristics desired for high voltage equipment. The resulting analysis is displayed in Table 4. The multi-objective optimization shows that two oil samples exhibited the best performance - the nanofluids with 0.6 and 0.8 wt% M2O3 nanoparticles. However, to save costs and to reduce agglomeration of nanoparticles in

the fluid, the nanofluid with 0.6 wt% AhO3 is the most promising candidate for high voltage equipment. In addition, it is recommended to study the effect of AhO3 nanoparticles using the 1wt% stepwise increase instead of the used 2wt% stepwise increase of activation energy and breakdown voltage of ester oil. This will show that perhaps 0.7 wt% has better activation energy and breakdown voltage.

Table 4 - Partial (Pij) and total preferable (Pt) probabilities of activation energy and

breakdown voltage of various fluids Таблица 4 - Частичная (Pij) и полная (Pt) предпочтительные вероятности

энергии активации и напряжения пробоя различных жидкостей Табела 4 - Делимичне (Pij) и укупне (Pt) поже^не вероватноПе активационе енерги]е и напона пуцаша разних флуида

Samples Pij of activation energy Pij of breakdown voltage (kV) Pt*100 Rank

Ester oil 0.052 0.072 0.372 9

Ester + 0.2 wt% ДЬОз 0.117 0.079 0.917 4

Ester + 0.4 wt% ДЬОз 0.117 0.092 1.077 2

Ester + 0.6 wt% ДЬОз 0.117 0.099 1.157 1

Ester + 0.8 wt% ДЬОз 0.117 0.099 1.157 1

Ester + 1 wt% ДЬОз 0.117 0.092 1.077 2

Ester + 0.2 wt% TO2 0.061 0.089 0.542 8

Ester + 0.4wt% TO2 0.061 0.092 0.562 7

Ester + 0.6 wt% TO2 0.065 0.096 0.621 6

Ester + 0.8 wt% TO2 0.078 0.096 0.745 5

Ester + 1 wt% TO2 0.104 0.096 0.993 3

Physicochemical characteristics and dielectric strength

Garba et al (2013) produced Jatropha oil, examined its properties, and compared it with diesel oil and transformer oil to see which one would perform better for transformer application. The performance characteristics of various oils are displayed in Table 5.

The flash point and dielectric strength were analyzed using the beneficial utility index (see Table 1) while the rest of the characteristics in Table 5 were analyzed using the unbeneficial utility index (see Table 2). The result showed that the developed Jatropha oil exhibited lesser performance for high voltage equipment compared to the other two

standard oils. This means that further study is essential to improve the performance characteristics of Jatropha oil for high voltage equipment. Many reports have shown that the addition of nanoparticles and the improvement of oil production can improve the performance efficiency of the oil for high voltage equipment (Jin et al, 2014; Peppas et al, 2016a, 2016b; Rafiq et al, 2016; Muangpratoom & Pattanadech, 2018; Oparanti et al, 2022).

Table 5 - Physicochemical characteristics and dielectric strength for high voltage

engineering

Таблица 5 - Физико-химические характеристики и диэлектрическая прочность

в области техники высоких напряжений Табела 5 -Физичко-хеми^ске карактеристике и диелектрична снага у области

енергетике високог напона

Oil samples Flash point (oC) Cloud point (oC) Viscosity (cst) Specific gravity Density (g/cm3) Dielectric strength (kV)

Diesel 65 5 2.86 0.792 0.8162 20

Jatropha oil 150 14 8.2 0.848 0.725 22

Transformer oil 140 7 9.3 0.89 0.89 24

Table 6 - Partial (Pij) and total preferable (Pt) probabilities of the physicochemical

properties and dielectric strength of fluids Таблица 6 - Частичная (Pij) и полная (Pt) предпочтительные вероятности физико-химических характеристик и диалектрической прочности жидкостей Табела 6 - Делимичне (Pij) и укупне (Pt) поже^не вероватноПе физичко-хеми^ских карактеристика и диелектричне снаге флуида

Oil samples (Pij) of flash point (Pij) of cloud point (Pij) of viscosity (Pij) of specific gravity (Pij) of density (Pij) of dielectric strength Pi*1000 Rank

Diesel 0.183 0.448 0.577 0.356 0.647 0.303 3.302 1

Jatropha oil 0.423 0.16 0.246 0.334 0.721 0.333 1.331 3

Transformer oil 0.395 0.384 0.177 0.317 0.587 0.364 1.817 2

Abeysundara et al (2001) produced a coconut oil, evaluated its performance characteristics and compared it with a standard oil for high voltage equipment. The properties of the two different oil types are presented in Table 7.

Table 7 - Properties of coconut oil and standard oil Таблица 7 - Свойства кокосового масла и стандартного масел Табела 7 - Свойства кокосовог у^а и стандардног у^а

Oil type Dielectric strength (kV) Flash point (oC) Moisture content (mg/Kg) Viscosity (cst) Density (Kg/dm3)

Coconut oil 60 225 1 29 0.917

Standard oil 50 154 1.5 13 0.895

The multi-objective optimization analysis was done and presented in Table 8 based on the conditions in Table 1 and 2. It is interesting to note that the produced coconut oil exhibited a higher performance tendency for high voltage equipment compared to standard oil. This shows that it is a good candidate for high voltage engineering. Therefore, further study such as ageing, direct application of the oil in a typical high voltage equipment is recommended.

Table 8 - Partial (Pij) and total preferable (Pt) probabilities of the oil properties Таблица 8 - Частичные (Pij) и полные (Pt) предпочтительные вероятности

свойств масла

Табела 8 - Делимичне (Pij) и укупне (Pt) поже^не вероватноПе своjстава у^а

Oil type (Pij) of dielectric strength (Pij) of flash point (Pij) of moisture content (Pij) of viscosity (Pij) of density Pt Rank

Coconut oil 0.546 0.594 0.6 0.312 0.492 2.984 1

Standard oil 0.455 0.406 0.4 0.696 0.504 2.593 2

Conclusion

This study successfully introduced and employed a probability-based multi-response optimization technique in the selection of high voltage thermofluids. The results showed the possibility of the employment of the probability-based multi-objective optimization technique in the production and selection of high voltage equipment oil. It was found out that the nanofluid with 0.6 wt% M2O3 is the most promising candidate for high voltage equipment compared to other produced fluids in the study of Oparanti et al (2021a). It is also noteworthy to state that coconut oil exhibited better performance efficiency compared to standard oil in the study of Abeysundara et al (2001). However, this study identifies that Jatropha oil produced by Garba et al (2013) was inadequate for high voltage equipment. Hence, preliminary study essential for the final usage

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of 0.6 wt% Al2O3 nanofluids and coconut oil for high voltage equipment should be done while the performance characteristics of Jatropha oil for high voltage equipment should be improved. In conclusion, the multi-objective optimization technique has been successfully employed in the selection of fluids for high voltage equipment. It is clear from the study that the analysis is simple to apply. Hence, it is recommended that the probability multi-objective optimization technique be subsequently employed when selecting the most efficient fluid for high voltage equipment.

References

Abd-Elhady, A.M., Ibrahim, M.E., Taha, T.A. & Izzularab, M.A. 2018. Effect of temperature on AC breakdown voltage of nanofilled transformer oil. IET Science, Measurement & Technology, 12(1), pp.138-144. Available at: https://doi.org/10.1049/iet-smt.2017.0217.

Abeysundara, D.C., Weerakoon, C., Lucas, J.R., Gunatunga, K.A.I. & Obadage, K.C. 2001. Coconut oil as an alternative to transformer oil. ResearchGate [online]. Available at:

https://www.researchgate.net/publication/268414369_Coconut_oil_as_an_altern ative_to_transformer_oil [Accessed: 5 January 2022].

Abifarin, J.K. 2021. Taguchi grey relational analysis on the mechanical properties of natural hydroxyapatite: effect of sintering parameters. The International Journal of Advanced Manufacturing Technology, 117, pp.49-57. Available at: https://doi.org/10.1007/s00170-021-07288-9.

Abifarin, J.K., Fidelis, F.B., Abdulrahim, M.Y., Oyedeji, E.O., Nkwuo, T. & Prakash, C. 2022. Response Surface Grey Relational Analysis On The Manufacturing of High Grade Biomedical Ti-13Zr-13Nb (preprint). The International Journal of Advanced Manufacturing Technology. Available at: https://doi.org/10.21203/rs.3Ts-1225030/v1.

Abifarin, J.K. & Ofodu, J.C. 2022. Modeling and Grey Relational Multi-response Optimization of Chemical Additives and Engine Parameters on Performance Efficiency of Diesel Engine. International Journal of Grey Systems, in press. Available at: https://doi.org/10.52812/ijgs.33.

Abifarin, J.K., Olubiyi, D.O., Dauda, E.T. & Oyedeji, E.O. 2021c. Taguchi grey relational optimization of the multi-mechanical characteristics of kaolin reinforced hydroxyapatite: effect of fabrication parameters. International Journal of Grey Systems, 1(2), pp.20-32. Available at: https://doi.org/10.52812/ijgs.30.

Abifarin, J.K., Prakash, C. & Singh, S. 2021b. Optimization and significance of fabrication parameters on the mechanical properties of 3D printed chitosan/PLA scaffold. Materials Today: Proceedings. Available at: https://doi.org/10.1016Zj.matpr.2021.09.386.

Abifarin, J.K., Suleiman, M.U., Abifarin, E.A., Fidelis, F.B., Oyelakin, O.K., Jacob, D.I. & Abdulrahim, M.Y. 2021a. Fabrication of mechanically enhanced hydroxyapatite scaffold with the assistance of numerical analysis. The International Journal of Advanced Manufacturing Technology, pp.1-14. Available at: https://doi.org/10.1007/s00170-021-08184-y.

Ashby, M.F. 2000. Multi-objective optimization in material design and selection. Acta materialia, 48(1), pp.359-369. Available at: https://doi.org/10.1016/S1359-6454(99)00304-3.

Ashby, M.F., Brechet, Y.J.M., Cebon, D. & Salvo, L. 2004. Selection strategies for materials and processes. Materials & Design, 25(1), pp.51-67. Available at: https://doi.org/10.1016/S0261-3069(03)00159-6.

Asse, J.B., Mengounou, G.M. & Imano, A.M. 2022. Impact of FeO3 on the AC breakdown voltage and acidity index of a palm kernel oil methyl ester based nanofluid. Energy Reports, 8, pp.275-280. Available at: https://doi.org/10.1016/j.egyr.2021.11.291.

Awodi, E., Ishiaku, U.S., Yakubu, M.K. & Abifarin, J.K. 2021. Experimentally Predicted Optimum Processing Parameters Assisted by Numerical Analysis on the Multi-physicomechanical Characteristics of Coir Fiber Reinforced Recycled High Density Polyethylene Composites (preprint). Available at: https://doi.org/10.21203/rs.3.rs-591200/v1.

Badicu, L.V., Dumitran, L.M., Notingher, P.V., Setnescu, R. & Setnescu, T. 2011. Mineral oil lifetime estimation using activation energy. In: 2011 IEEE International Conference on Dielectric Liquids, Trondheim, Norway, pp.1-4, June 26-30. Available at: https://doi.org/10.1109/ICDL.2011.6015463.

Deshmukh, D. & Angira, M. 2019. Investigation on switching structure material selection for RF-MEMS shunt capacitive switches using Ashby, TOPSIS and VIKOR. Transactions on Electrical and Electronic Materials, 20(3), pp.181188. Available at: https://doi.org/10.1007/s42341-018-00094-3.

Du, J.L., Huang, J., Hu, Y. & Wang, X.F. 2013. Determination of trace lead in beer by cloud point extraction-flame absorption spectrometry. Science and Technology of Food Industry, 11, pp.303-306 [online]. Available at:

http://caod.oriprobe.com/articles/38800347/zhuo_dian_zuo_qu_huo_yan_yua

n_zi_xi_shou_guang_pu_fa_ce_ding_pi_jiu_.htm [Accessed: 5 January 2022].

Garba, Z.N., Gimba, C.E., & Emmanuel, P. 2013. Production and characterisation of biobased transformer oil from Jatropha Curcas Seed. Journal of Physical Science, 24(2), p.49-61 [online]. Available at: https://jps.usm.my/jatropha-curcas-seed/ [Accessed: 5 January 2022].

Ghoneim, S.S., Dessouky, S. ., Boubakeur, A., Elfaraskoury, A.A., Abou Sharaf, A.B., Mahmoud, K., Lehtonen, M. & Darwish, M.M.F. 2021. Accurate Insulating Oil Breakdown Voltage Model Associated with Different Barrier Effects. Processes, 9(4), art.number:657. Available at: https://doi.org/10.3390/pr9040657.

Gong, H., Yu, B., Dai, F., Peng, Y. & Shao, J. 2018. Simulation on performance of a demulsification and dewatering device with coupling double fields: Swirl centrifugal field and high-voltage electric field. Separation and

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Purification Technology, 207, pp.124-132. Available at: https://doi.org/10.1016/j.seppur.2018.06.049.

Hosier, I.L., Guushaa, A., Vaughan, A.S. & Swingler, S.G. 2009. Selection of a suitable vegetable oil for high voltage insulation applications. Journal of Physics: Conference Series, 183(1), art.ID:012014. Available at: https://doi.org//10.1088/1742-6596/183/1 /012014.

Hosier, I.L., Vaughan, A.S. & Montjen, F.A. 2006. Ageing of biodegradable oils for high voltage insulation systems. In: 2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena, Kansas City, MO, USA, pp. 481-484, October 15-18. Available at: https://doi.org/10.1109/CEIDP.2006.311974.

Jin, H., Andritsch, T., Tsekmes, I.A., Kochetov, R., Morshuis, P.H. & Smit, J.J. 2014. Properties of mineral oil based silica nanofluids. IEEE Transactions on Dielectrics and Electrical Insulation, 21(3), pp.1100-1108. Available at: https://doi.org/10.1109/TDEI.2014.6832254

Kumar, S.S., Iruthayarajan, M.W. & Bakrutheen, M. 2014. Analysis of vegetable liquid insulating medium for applications in high voltage transformers. In: 2014 International Conference on Science Engineering and Management Research (ICSEMR), Chennai, India, pp.1-5, November 27-29. Available at: Available at: https://doi.org/10.1109/ICSEMR.2014.7043606.

Lee, J.C., Seo, H.S. & Kim, Y.J. 2012. The increased dielectric breakdown voltage of transformer oil-based nanofluids by an external magnetic field. International Journal of Thermal Sciences, 62, pp.29-33. Available at: https://doi.org/10.1016/j.ijthermalsci.2012.03.013

Lin, C.M., Herianto, S., Syu, S.M., Song, C.H., Chen, H.L. & Hou, C.Y. 2021. Applying a large-scale device using non-thermal plasma for microbial decontamination on shell eggs and its effects on the sensory characteristics. LWT, 142, art.ID:111067. Available at: https://doi.org/10.1016/j.lwt.2021.111067.

Liu, J., Fan, X., Zhang, Y., Zheng, H. & Jiao, J. 2020. Temperature correction to dielectric modulus and activation energy prediction of oil-immersed cellulose insulation. IEEE Transactions on Dielectrics and Electrical Insulation, 27(3), pp.956-963. Available at: https://doi.org/10.1109/TDEI.2019.008530.

Liu, J., Fan, X., Zheng, H., Zhang, Y., Zhang, C., Lai, B., Wang, J., Ren, G. & Zhang, E. 2019. Aging condition assessment of transformer oil-immersed cellulosic insulation based upon the average activation energy method. Cellulose, 26(6), pp.3891-3908. Available at: https://doi.org/10.1007/s10570-019-02331-1.

Minkner, R. & Schmid, J. 2022. The Technology of Instrument Transformers. Current and Voltage Measurement and Insulation Systems. Springer Fachmedien Wiesbaden. Available at: https://doi.org/10.1007/978-3-658-34863-2. ISBN: 9783-658-34863-2.

Muangpratoom, P. & Pattanadech, N. 2018. Breakdown and partial discharge characteristics of mineral oil-based nanofluids. IET Science, Measurement & Technology, 12(5), pp.609-616. Available at: https://doi.org/10.1049/iet-smt.2017.0080.

Ofodu, J.C. & Abifarin, J.K. 2021. Physicochemical and dissolved gas analysis of an in-service transformer oils in Benin, Edo State, Nigeria. Journal of Applied Sciences and Environmental Management, in press.

Oparanti, S.O., Abdelmalik, A.A., Khaleed, A.A., Abifarin, J.K., Suleiman, M.U. & Oteikwu, V.E. 2022. Synthesis and characterization of cooling biodegradable nanofluids from non-edible oil for high voltage application. Materials Chemistry and Physics, 277, art.ID:125485. Available at: https://doi.org/10.1016/j.matchemphys.2021.125485.

Oparanti, S.O., Khaleed, A.A. & Abdelmalik, A.A. 2021a. Nanofluid from Palm Kernel Oil for High Voltage Insulation. Materials Chemistry and Physics, 259, art.ID:123961. Available at:

https://doi.org/10.1016/j.matchemphys.2020.123961.

Oparanti, S.O., Khaleed, A.A. & Abdelmalik, A.A. 2021b. AC breakdown analysis of synthesized nanofluids for oil-filled transformer insulation. The International Journal of Advanced Manufacturing Technology, 117(5), pp.13951403. Available at: https://doi.org/10.1007/s00170-021-07631-0.

Oparanti, S.O., Khaleed, A.A., Abdelmalik, A.A. & Chalashkanov, N.M. 2020. Dielectric characterization of palm kernel oil ester-based insulating nanofluid. In: 2020 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP), East Rutherford, NJ, USA, pp.211-214, October 18-30. Available at: https://doi.org/10.1109/CEIDP49254.2020.9437477.

Oyelaran, O.A., Bolaji, B.O. & Samuel, O.D. 2020. Assessment of calabash seed oil as biobased insulating fluid for power transformers. Journal of Chemical Technology and Metallurgy, 55(2), pp.307-313 [online]. Available at: http://repository.fuoye.edu.ng/handle/123456789/2317 [Accessed: 5 January 2022].

Peppas, G.D., Bakandritsos, A., Charalampakos, V.P., Pyrgioti, E.C., Tucek, J., Zboril, R. & Gonos, I.F. 2016a. Ultrastable Natural Ester-Based Nanofluids for High Voltage Insulation Applications. ACS Applied Materials & Interfaces, 8(38), pp.25202-25209. Available at: https://doi.org/10.1021/acsami.6b06084.

Peppas, G.D., Charalampakos, V.P., Pyrgioti, E.C., Danikas, M.G., Bakandritsos, A. & Gonos, I.F. 2016b. Statistical investigation of AC breakdown voltage of nanofluids compared with mineral and natural ester oil. IET Science, Measurement & Technology, 10(6), pp.644-652. Available at: https://doi.org/10.1049/iet-smt.2016.0031.

Rafiq, M., Lv, Y. & Li, C. 2016. A review on properties, opportunities, and challenges of transformer oil-based nanofluids. Journal of nanomaterials, 2016, art.ID 8371560. Available at: https://doi.org/10.1155/2016/8371560.

Sitinjak, F., Suhariadi, I. & Imsak, L. 2003. Study on the characteristics of palm oil and it's derivatives as liquid insulating materials. In: Proceedings of the 7th International Conference on Properties and Applications of Dielectric Materials (Cat. No. 03CH37417), Nagoya, Japan, 2, pp.495-498, June 1-5. Available at: https://doi.org/10.1109/ICPADM.2003.1218461.

Srinivasa, D.M. & Surendra, U. 2019. Comparative study of breakdown phenomena and viscosity in liquid dielectrics. In: 2019 Innovations in Power and

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Wang, Y. & Teng, H. 2021. A New" Intersection" Method for Multi-Objective Optimization in Material Selection. Tehnicki glasnik, 15(4), pp.562-568. Available at: https://doi.org/10.31803/tg-20210901142449.

Yaacob, M.M. & Alsaedi, M.A. 2015. Use palm oil as alternative with insulation oil in high voltage equipment. Physical Science International Journal, 5(3), pp.172-178 [online] Available at:

https://www.journalpsij.com/index.php/PSIJ/article/view/23629 [Accessed: 5 January 2022].

Zhang, M., Li, L., Liu, H., Jia, H., Liu, J. & Meng, F. 2021. Method for quantitative assessment of transformer oil-paper insulation non-uniform ageing parameters based on frequency domain dielectric response. IET Science, Measurement & Technology. Available at: https://doi.org/10.1049/smt2.12091.

Zheng, M. 2022. Application of probability-based multi-objective optimization in material engineering. Vojnotehnicki glasnik/Military Technical Courier, 70(1), pp. 1-12. Available at: https://doi.org/10.5937/vojtehg70-35366.

ПРИМЕНЕНИЕ ОПТИМИЗАЦИИ С НЕСКОЛЬКИМИ ВЫХОДАМИ, ОСНОВАННОЙ НА ВЕРОЯТНОСТИ, ДЛЯ ЖИДКИХ ТЕПЛОНОСИТЕЛЕЙ ВЫСОКОВОЛЬТНОГО ОБОРУДОВАНИЯ

Джозеф Чуквука Офодуа, Джонсон Кехинде Aбифаринб а Университет Порт-Харкорта, инженерный факультет, кафедра машиностроения, г. Чоба, штат Риверс, Федеративная Республика Нигерия

б Университет Ахмаду Белло, инженерный факультет, кафедра машиностроения, г. Зария, Федеративная Республика Нигерия, корреспондент

РУБРИКА ГРНТИ: 30.17.00 Механика жидкости и газа,

47.09.00 Материалы для электроники и радиотехники ВИД СТАТЬИ: оригинальная научная статья

Резюме:

Введение/цель: Исследователи, занимающиеся жидкостями, предназначенными для использования в технике высоких напряжений, зачастую сталкиваются с проблемами при выборе или при рекомендации соответствующей жидкости, подходящей для использования в технике высоких напряжений. Это связано с двойной функциональностью жидкостей, необходимых для высоковольтного оборудования.

Методы: В данной статье представлен и применен метод многоцелевой оптимизации, основанный на вероятности, при выборе теплоносителя для высоковольтного оборудования. В

зависимости от ожидаемых характеристик масла применялись индексы предпочтительной вероятности полезности, типа «чем больше, тем лучше» и «чем меньше, тем лучше».

Результаты: Результаты исследования показали, что наножидкость с содержанием 0.6 Ы% ЛЬОэ является наиболее перспективным кандидатом для высоковольтного оборудования по сравнению с другими испытанными жидкостями. Также важно отметить, что кокосовое масло показало лучшие результаты по сравнению со стандартным маслом. В ходе исследования также выявлено, что выработанное масло ятрофы непригодно для высоковольтного оборудования.

Выводы: Рекомендуется провести предварительное исследование, необходимое для конечного использования наножидкостей с содержанием 0.6 Ы%о ЛЬОэ, а также кокосового масла в технике высокого напряжения. Также рекомендуется улучшить характеристики масла, выработанного из растения ятрофа для использования в технике высокого напряжения.

Ключевые слова: оптимизация предпочтительной вероятности, высоковольтное оборудование, теплоносители, физико-химические свойства, диэлектрическая прочность.

ПРИМЕНА ОПТИМИЗАЦШЕ СА ВИШЕ ИЗЛАЗА ЗАСНОВАНЕ НА ВЕРОВАТНОЪИ ФЛУИДА ДА ПРЕНОСЕ ТОПЛОТУ У ВИСОКОНАПОНС^ ОПРЕМИ

Цосеф Чуквука Офодуа, Цонсон Кехинде Абифарин6

а Универзитет у Порт Харкорту, Факултет техничких наука, одсек за машинство, Чоба, Држава Риверс, Савезна Република Нигери]а

б Универзитет Ахмаду Белло, Факултет техничких наука, одсек за машинство, Зариа, Савезна Република Нигер^а, аутор за преписку

ОБЛАСТ: машинство, матери]али ВРСТА ЧЛАНКА: оригинални научни рад

Сажетак:

Увод/цил>: При избору одговара}уЬег флуида погодог за примену у високонапонско] опреми наилази се на проблеме. Узрок томе }е двострука функционалност флуида ко}а се захтева за високонапонску опрему.

Методе: Ова] рад уводи и примере технику вишециъне оптимизаци]е засноване на вероватноЬи приликом селекци}е флуида за пренос топлоте у високонапонско] опреми. Индекси корисности пожеъне вероватноЬе типа „што више - то боъе" и

^ типа „што маше - то боле " примешени су зависно од желених

карактеристика ула.

Резултати: Показано je да je нанофлуид са 0,6 wt% AI2O3 ^ наjпогодниjи за високонапонску опрему у односу на остале

° разматране произведене флуиде. Важно je поменути да je кокосово

с\Г см

о

уле показало боле перформансе у поре^ешу са стандардним улем.

g Указано je, тако^е, и да произведено уле билке Jatropha н^е

Г

погодно за високонапонску опрему. Ш Заклучак: Препоручу/е се прелиминарна студ^а, неопходна за

краjшe коришЯеше нанофлуида са 0,6 wt% А20з,као и кокосовог ула § за високонапонску опрему. Тако^е, препорука je да се

поболшаjукаракmeрисmикe ула билке Jatropha ради коришЯеша у

0 високонапонсщ опреми.

1 Клучне речи: оптимизац^а пожелне вероватноПе, ш високонапонска опрема, флуиди за пренос топлоте, физичко-

хем^ска своjсmва, диелектрична снага.

СС

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Paper received on / Дата получения работы / Датум приема чланка: 06.01.2022. Manuscript corrections submitted on / Дата получения исправленной версии работы / Датум достав^а^а исправки рукописа: 10.03.2022.

Paper accepted for publishing on / Дата окончательного согласования работы / Датум ^ коначног прихвата^а чланка за об]ав^ива^е: 12.03.2022.

О © 2022 The Authors. Published by Vojnotehnicki glasnik / Military Technical Courier

(www.vtg.mod.gov.rs, втг.мо.упр.срб). This article is an open access article distributed under О the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/rs/).

¡f! © 2022 Авторы. Опубликовано в «Военно-технический вестник / Vojnotehnicki glasnik / Military

О Technical Courier» (www.vtg.mod.gov.rs, втг.мо.упр.срб). Данная статья в открытом доступе

_ и распространяется в соответствии с лицензией «Creative Commons»

^ (http://creativecommons.org/licenses/by/3.0/rs/).

^ © 2022 Аутори. 06jaeno Во]нотехнички гласник / Vojnotehnicki glasnik / Military Technical Courier (www.vtg.mod.gov.rs, втг.мо.упр.срб). Ово ]е чланак отвореног приступа и дистрибуира се у складу са Creative Commons licencom (http://creativecommons.org/licenses/by/3.0/rs/).