Investigation of the Effect of Using Electromechanical Valve Mechanism on Air Flow Parameters in Spark Ignition Single Cylinder Engine with CFD Method

Öz

In this study, the effect of using electromechanical valve mechanism instead of standard cam mechanism of a spark ignition single cylinder engine on the in-cylinder flow parameters was investigated with Computational Fluid Dynamics (HAD) software. With the classical cam mechanism, the pressure inside the cylinder at different speeds and the flow rate of the air entering the cylinder through the manifold were measured experimentally. After experimental measurements, in-cylinder flow simulations were performed using Ansys FORTE software, which is Computational Fluid Dynamics Software. The experimental measurements made with the standard cam mechanism and the analyzes made with the standard cam mechanism were verified. The use of the electromechanical valve mechanism according to the standard valve opening times of the engine was examined. After verifying these measured values ​​with the analysis results, the effect of rotation on values ​​such as horizontal vortex and vertical vortex, which cannot be measured experimentally and have an effect on the combustion efficiency, has been revealed with the analysis results. In the analysis study, a literature search was made for the electromechanical valve profile and the most ideal valve opening time was determined and according to this time, electromechanical valve profiles were created for different speeds. It has been observed that there are improvements in the volumetric efficiency of the engine when the electromechanical valve mechanism is used. This study revealed that the increase in volumetric efficiency has positive effects on the combustion efficiency indirectly.

Anahtar Kelimeler

• Computational Fluid Dynamic
• In-Cylinder Flow Modeling,
• Electromechanical Valve Mechanism

Buji Ateşlemeli Tek Silindirli Motorda Elektromekanik Supap Mekanizmasının Kullanılmasının Hava Akış Parametrelerine Etkisinin HAD Yöntemi İle İncelenmesi

Öz

Bu çalışmada buji ateşlemeli tek silindirli bir motorun standart kam mekanizması yerine elektromekanik supap mekanizması kullanılmasının silindir içi akış parametrelerine etkisi Hesaplamalı Akışkanlar Dinamiği (HAD) yazılımı ile incelenmiştir. Klasik kam mekanizması ile farklı devirlerde silindir içi basınç ve manifold üzerinden silindire giren havanın debisi deneysel olarak ölçülmüştür. Deneysel ölçümlerden sonra Hesaplamalı Akışkanlar Dinamiği Yazılımı olan Ansys FORTE yazılımı kullanılarak silindir içi akış simülasyonları gerçekleştirilmiştir. Standart Kam Mekanizması ile yapılan deneysel ölçümler ile standart kam mekanizması ile yapılan analizler doğrulama çalışmaları yapılmıştır. Elektromekanik supap mekanizmasının motorun standart supap açılma zamanlarına göre kullanılması durumu incelenmiştir. Bu ölçülen değerlerde analiz sonuçları ile doğrulaması yapıldıktan sonra deneysel olarak ölçülemeyen ve yanma verimliliğine etkisi olan yatay girdap, dikey girdap gibi değerlere devirin etkisi analiz sonuçları ile ortaya konmuştur. Analiz çalışmasında elektromekanik supap profili için literatür araştırması yapılmış ve en ideal supap açılma süresi belirlenmiş ve bu süreye göre elektromekanik supap profilleri farklı devirler için oluşturulmuştur. Elektromekanik supap mekanizması kullanılması durumunda motorun volumetrik veriminde iyileşmeler olduğu görülmüştür. Volumetrik verimin artması dolaylı yoldan yanma verimliliğine olumlu etkilerin olduğu bu çalışmayla ortaya konmuştur.

Anahtar Kelimeler

• Hesaplamalı Akışkanlar Dinamiği
• Silindir İçi Akış Modellenmesi
• Elektromekanik Supap Mekanizması

Kaynakça

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