HİDROLİK SİSTEMLERDEKİ ENERJİ VERİMLİLİĞİ

Bu çalışmada, keyfi başlangıç fonksiyonuna sahip hafifçe eğri bir kirişin lineer olmayan titreşimleri ele alınmaktadır. Her iki ucundan elastik mesnetler kullanılarak kiriş, boyuna yönünde kısıtlanmıştır. Başlangıçta sinüsoidal eğrilik fonksiyonuna sahip olduğu varsayılan kiriş için, ulaşılan eğrilik yüksekliğinin izdüşüme oranı 1/10 alınmaktadır. Euler-Bernoulli tipinde olan kiriş Winkler elastik zemini üzerine oturmakta ve üzerinde keyfi olarak yerleştirilmiş kütleler taşımaktadır. Hamilton prensibi kullanılarak hareket denklemleri elde edilmiştir. Zeminden ve kiriş uzamasından dolayı matematiksel modelde kübik ve quadratik lineer olmayan terimler ortaya çıkmaktadır. Hareket denklemlerini analitik olarak çözümlemek için bir Pertürbasyon tekniği olan Çok Ölçekli Metod(MMS) kullanılmaktadır. Geçici-durum titreşimleri süresince baskın rezonans durumu dikkate alınmaktadır. Mesnetlerin tipleri, kütlelerin konumları ve zeminin lineer bileşeni gibi farklı mukayese parametreleri için doğal frekanslar elde edilmektedir. Genlik-faz modülasyon denklemleri kullanılarak frekans-genlik ve frekans-cevap grafikleri çizilmiştir.

Anahtar Kelimeler:

Hidrolik devre, Hidrolik motor, Elektro-hidrolik hareketlendirici, Basınç dengeli Hidrolik sistem

Energy Efficiency in Hydraulic Systems

The development of hydraulic systems and the reduction of energy losses have provided by very serious scientific studies related to these systems recently. Energy losses consist of friction in pipes, equipment, elbows and diameter changes. The hydraulic pressure losses that cause the heat increase will require the use of a cooler, as it will damage the system. Another energy loss is due to fluid leakages, which are initially small but increase over time. In addition, the fluid returning to the tank through the safety valve also increases the energy loss. Equipment and technological improvements, in hydraulic systems, reduce the energy losses. In order to facilitate the pressure control in the system, the high-pressurized liquid discharge in return line, passed through the safety valve installed into the closest to the pump is increased. The role of the hydraulic system in industrial development is increasingly taking the place of digital control systems, which is a much more economical alternative. In this study, conventional and energy efficient systems are compared with valve and pump-controlled mobile devices.

Keywords:

Hydraulic circuit, Hydraulic motor, Electro-hydraulic actuator, Pressure compensated Hydraulic system,

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