|
|
Cavitating jet
Kotoulová, Helena ; Kozák, Jiří (oponent) ; Rudolf, Pavel (vedoucí práce)
This diploma’s thesis deals with the cavitating liquid jet and cavitation erosion models. It is divided into three main parts. The theoretical part describes the fundamental principles of cavitation and its negative effects on the surface of circumflowed solid materials (e.g. at hydraulic machines). An extensive chapter is also devoted to a description of the cavitating liquid jet itself, including the mechanisms of its inception, growth and collapse. Another subchapter focuses on cavitation erosion models, which are of great importance for a prediction of the cavitation erosion in the phase of computational simulation. In the experimental part, a copper sample was exposed to the cavitating jet in a test rig inspired by ASTM G134 standard and consequently, graphs of cumulative mass loss and mass loss rate were created. In addition, a visualization using high-speed camera was performed for better understanding of the cavitating liquid jet dynamic behavior. The last part focuses on numerical simulations using Computational Fluid Dynamics (CFD) and the cavitation erosion prediction. Multiple computations were performed on different types of mesh with different turbulence models in order to optimize the numerical simulation. Subsequently, the results from the simulations were evaluated and used together with the results from the experiment to predict cavitation erosion.
|
|
|
Cavitation erosion mechanisms
Kotoulová, Helena ; Kozák, Jiří (oponent) ; Rudolf, Pavel (vedoucí práce)
This bachelor’s thesis deals with mechanisms of cavitation erosion and it is divided into two main parts. The theoretical part describes the principle of cavitation, its inception and mainly the collapse of the cavitation bubbles, which negatively affects the surface of circumflowed solid materials (e.g. at hydraulic machines). For this reason, it is necessary to gain thorough knowledge of the effects of the cavitation erosion. The experimental part is devoted to cavitation erosion testing of 3D printed metal and plastic samples. The plastic samples were compared with each other and the 3D printed metal samples with the cast ones. The influence of cavitation erosion on 3D manufactured samples is still rather unknown, although it is a very progressive type of manufacturing.
|
|
|
Cavitating jet
Kotoulová, Helena ; Kozák, Jiří (oponent) ; Rudolf, Pavel (vedoucí práce)
This diploma’s thesis deals with the cavitating liquid jet and cavitation erosion models. It is divided into three main parts. The theoretical part describes the fundamental principles of cavitation and its negative effects on the surface of circumflowed solid materials (e.g. at hydraulic machines). An extensive chapter is also devoted to a description of the cavitating liquid jet itself, including the mechanisms of its inception, growth and collapse. Another subchapter focuses on cavitation erosion models, which are of great importance for a prediction of the cavitation erosion in the phase of computational simulation. In the experimental part, a copper sample was exposed to the cavitating jet in a test rig inspired by ASTM G134 standard and consequently, graphs of cumulative mass loss and mass loss rate were created. In addition, a visualization using high-speed camera was performed for better understanding of the cavitating liquid jet dynamic behavior. The last part focuses on numerical simulations using Computational Fluid Dynamics (CFD) and the cavitation erosion prediction. Multiple computations were performed on different types of mesh with different turbulence models in order to optimize the numerical simulation. Subsequently, the results from the simulations were evaluated and used together with the results from the experiment to predict cavitation erosion.
|
|
|
Cavitation erosion mechanisms
Kotoulová, Helena ; Kozák, Jiří (oponent) ; Rudolf, Pavel (vedoucí práce)
This bachelor’s thesis deals with mechanisms of cavitation erosion and it is divided into two main parts. The theoretical part describes the principle of cavitation, its inception and mainly the collapse of the cavitation bubbles, which negatively affects the surface of circumflowed solid materials (e.g. at hydraulic machines). For this reason, it is necessary to gain thorough knowledge of the effects of the cavitation erosion. The experimental part is devoted to cavitation erosion testing of 3D printed metal and plastic samples. The plastic samples were compared with each other and the 3D printed metal samples with the cast ones. The influence of cavitation erosion on 3D manufactured samples is still rather unknown, although it is a very progressive type of manufacturing.
|
host ::
RSS.