Bir otomobil salıncağının topoloji optimizasyonu
Topology optimization of an automobile wishbone
Yazar: ABDULKADİR NAZLI
Danışman: DR. ÖĞR. ÜYESİ NESLİHAN ÖZSOY
Sakarya Üniversitesi / Fen Bilimleri Enstitüsü / Makine Mühendisliği Ana Bilim Dalı / Makine Tasarım ve İmalat Bilim Dalı
Derece: Yüksek Lisans, 2023
Konu: Makine Mühendisliği = Mechanical Engineering
Dizin: Topoloji optimizasyonu = Topology optimization

Özet:
Otomotiv endüstrisindeki rekabetin arttığı son yıllarda teknolojinin ve imkanların genişlemesiyle, üreticiler otomobil parçalarında önemli iyileştirmeler yapabilir duruma gelmiştir. Bu iyileştirmelere kalitenin arttırılması, maliyetlerin azaltılması gibi örnekler verebiliriz. Üreticiler daima kısa sürede, uygun maliyete, en uygun satış fiyatına ve kaliteye sahip olacak ürünler üretmeyi hedeflemektedir. Otomotiv üreticileri de yaptıkları iyileştirmeler sayesinde rakiplerinin önüne geçebilmektedirler. Bu iyileştirmeler kapsamındaki en önemli olanı gereksiz malzeme tüketimini ortadan kaldırmaktır. Gereksiz malzemelerin ortadan kaldırılmasıyla üretilen araçlardaki ağırlığının azalması sağlanmaktadır. Buna bağlı olaraktan yakıt tüketiminde azalma ve enerji kullanım verimliliğinde artma sağlanacaktır. Yakıt tüketiminde düşüş sağlanarak doğaya salınan zararlı emisyon gaz oranlarında da azalma görülmektedir. Bu bağlamda tasarım iyileştirme süreçleri ele alındığında optimum sonuca hızlı, ucuza ve doğru şekilde yakınsayan yöntemlerin kullanılması gerekmektedir. Parçalardaki ağırlığı azaltmak için malzeme dağılımını en etkin görebileceğimiz yöntem topoloji optimizasyonudur. Topoloji optimizasyonu, belirli bir tasarım hacmi içerisinde, belirli sınır şartları ve kısıtlamaları için sayısal bir amaç fonksiyonu oluşturarak sonrasında bağlantı arayüzlerini değiştirmeden kullanılan malzeme miktarının en aza indirgenmesini sağlayan bir tasarım aracıdır. Topoloji optimizasyonun amacı; ağırlığı azaltmak, maliyeti azaltmak, üretilebilirliği kolaylaştırmak, sağlamlığı artırmak vb..'dir. 
Topoloji optimizasyonun uygulandığı sektörler; makine endüstrisi, otomotiv ana sanayii ve yan sanayi endüstrisi, savunma sanayi endüstrisi, inşaat sektörü, uzay-havacılık sanayi, sağlık sektörü gibi birçok alanda kullanıldığı uygulama alanları bulunmaktadır. Bu yöntem hızlı, çözüm odaklı ve maliyet olarak düşük bir yaklaşımdır. Bu tezde, bir otomobil salıncağına topoloji optimizasyonu yapılmasını ve çıkan sonuçların değerlendirmelerini içermektedir. Çıkan sonuca göre optimum ürün elde edilmesi hedeflenmiştir. Çalışmanın başlangıcında üç boyutlu modelleme çalışması, bilgisayar destekli tasarım aracı olan CATIA programında gerçekleştirilmiştir. Sonlu elemanlar analizinin uygulaması ve topoloji optimizasyonu aktiviteleri için bilgisayar destekli analiz programı olan ANSYS ile yürütülmüştür. Bu tezde yapılanlar yukarda belirtilen sektörlerde yapılacak benzer çalışmalara yol gösterip, firmalara ve akademik çalışanlara hitap edecektir.

Abstract:
The automotive industry is one of the main industries where studies on motor vehicles are carried out. The sub-parts of the vehicles produced in this sector are called automotive parts. An automotive product consists of many components, namely automotive parts. To develop or improve a motor vehicle, it may be sufficient to make any of its components more efficient. Making a part more efficient provides both functional and financial gains. Therefore, all automotive components are products of research and development. Thanks to developing technologies, it is becoming easier to implement these procedures.
Until recently, traditional manufacturing methods were generally used in the production of automotive parts. The products produced had extremely crude designs with high safety coefficients. Product development processes were carried out through trial and error. Thanks to computer-aided design programs, there have been revolutionary changes in product improvement and development processes. Topology optimization has recently become an important design activity in product development processes.
In the automotive industry, the process of developing products that will perform their duties at an optimum level is a very important part of determining the product cost. For this reason, it is necessary to obtain the most optimum design in terms of cost and durability during the product design period. The aim of the thesis will be to reveal the optimum design of the wishbone part in the suspension system of automobiles using the topology optimization method.
When we look at a total of 13 theses and articles examined in the literature review, it is seen that they coincide with the purpose of this thesis, the content of which is created in the following headings. The process and process flow process in all studies examined are similar. The studies carried out made great contributions to the creation of this thesis. The majority of the studies examined were taken from the automotive industry. First, a part belonging to an existing subsystem is selected. The boundary conditions of this part are determined, then the static analysis of the existing part is performed and the strength values of the part are obtained. According to the analysis results, topology optimization was performed and mitigation was performed on the part. The design verification of the lightened model is made by performing a static analysis on the lightened design again and checking whether it is within the strength values.
In recent years, when competition in the automotive industry has increased, with the expansion of technology and opportunities, manufacturers have become able to make significant improvements in automobile parts. We can give examples of these improvements, such as increasing quality and reducing costs. Manufacturers always aim to produce products with the best sales price and quality quickly at an affordable cost. Automotive manufacturers can also get ahead of their competitors thanks to the improvements they make. The most important of these improvements is to eliminate unnecessary material consumption. By eliminating unnecessary materials, the weight of the vehicles produced is reduced. Accordingly, a decrease in fuel consumption and an increase in energy use efficiency will be achieved. By reducing fuel consumption, there is also a decrease in the harmful emission gases released into nature. In this context, when design improvement processes are considered, methods that converge to the optimum result quickly, cheaply, and accurately should be used. The most effective method for reducing the weight of parts is topology optimization. Topology optimization is a design tool that creates a numerical objective function for certain boundary conditions and constraints within a specific design volume and then minimizes the amount of material used without changing the connection interfaces. Topology optimization aims to reduce weight, reduce cost, facilitate manufacturability, increase durability, etc.
In this thesis, topology optimization, topology optimizations made in the literature for the control arm part in the suspension system in the automotive industry, within the scope of the determined thesis title, were examined. Then, the wishbone model was created in CATIA V5 computer software, which is a three-dimensional design program. For topology optimization, optimization parameters were determined by establishing a finite element model in the analysis software. Static analysis was performed according to loads, boundary conditions and material data, and the strength values of the first design were obtained. The model obtained as a result of topology optimization was modeled again in three dimensions as a reproducible model. For validation, the new model is subjected to the static analysis process in the analysis program again and it is checked whether it complies with the strength values. As a result, the weight of the wishbone part was reduced and the analysis results showed that it had sufficient strength. The aim is to reduce costs by providing mitigation. In addition, thanks to the lightweighting, the damage to the environment has been reduced by reducing the exhaust emission values released into the environment. The improvements and observations obtained from the outputs of the design and analysis studies were evaluated and ideas were put forward about the work that could be done in the future.
Topology optimization is applied in many areas, such as the machinery industry, automotive main industry and sub-industry industry, defense industry, construction industry, aerospace industry and healthcare industry. This method is a fast, solution-oriented and low-cost approach. This thesis includes topology optimization of an automobile wishbone arm and evaluating the results. According to the results, it is aimed to obtain the optimum product. At the beginning of the study, three-dimensional modeling work was carried out in the CATIA program with computer-aided design. It was carried out with ANSYS, a computer-aided analysis program for applying finite element analysis and topology optimization activities. The work done in this thesis will guide similar studies to be carried out in the sectors mentioned above and will appeal to companies and academic personnel.
Considering that air pollution in our world is caused by cars with internal combustion engines, one of the solutions to reduce the harmful gases produced by cars and factories may be mass reduction. This approach will reduce the need for less energy consumption and fossil fuel consumption.
The study has shown us that this method can be applied not only in the automobile field but in every field of production. With the analysis to be made, we have seen that the products can be produced using less material without compromising their functionality and quality.
In automobiles, the weight component is of great importance for fuel consumption. As in the automobile industry, weight is more critical in defense industry vehicles. Because the power package is selected according to the power/weight ratio. At the same time, the weight component directly determines the range that the vehicles will travel.
By making topology optimizations in the design, it will be possible to significantly reduce production costs and stand out in the competitive environment by producing optimum parts. Thanks to this method, endless trial opportunities are provided during the design and production stages. Doing these results in cost reduction, labor burden reduction and time savings.
The lightness achieved as a result of the thesis study will not only save fuel in the automobile in which this part will be used, but will also benefit fuel savings in all vehicles that carry this part and consume energy. From the manufacturer's perspective, the time it takes to implement the change and turn a profit may vary.
The result of the study was a 42% reduction in part weight. As a result, the average fuel consumed per 100 km was reduced by 0.2%. Exhaust emissions are reduced by 0.58gr of CO2 per 100km. A product that is lighter in weight was created. Cost reduction has been achieved. Material savings were achieved. Contribution was made to reducing the emission value released into the environment. It has been seen that computer software makes great contributions to production, production and our progress. By performing design and analysis in a computer environment, savings can be achieved in the prototype and testing stages. In addition to saving time in these stages, it also eliminated prototyping and testing costs.