|
|
Influence of manufacturing process and precision on quality of liquid atomization from pressure-swirl atomizers
Lebeda, Kryštof ; Cejpek, Ondřej (referee) ; Malý, Milan (advisor)
The thesis deals with the effects of manufacturing inaccuracies and manufacturing method on the spray quality of pressure-swirl atomizers. First, basic principles of atomization are outlined. In the next section, observed atomization parameters of pressure swirl atomizers are discussed. This is followed by a research of available studies investigating influence of inaccuracies and manufacturing methods on selected parameters. In the practical part evaluation of measured data of pressure-swirl atomizers with defects at discharge orifice, different surface roughness and atomizers made by 3D printing was carried out. Skewness and misalignment of discharge orifice significantly reduced spray quality. No effect of surface roughness for conventionally manufactured nozzles was found. The use of 3D printing for nozzle production resulted in a deterioration of atomization fineness. Chamfering of dicharge orifice promoted larger spray cone angle but did not affect the atomization fineness.
|
|
|
Atomization mechanisms of liquid fuels
Buzík, Jiří ; Bělohradský, Petr (referee) ; Broukal, Jakub (advisor)
The bachelor thesis deals with the atomization of liquid fuels and their atomizers and mechanisms which are concerned in atomization. The main purpose of this thesis is to describe the problems that are connected with the atomization. The author gives information about the primary and secondary decomposition of liquid. One part of the thesis is the software which focuses on the statistic evaluation and comparison of information which are performed by available experiments and numeric calculations.
|
|
|
Testing of a transparent model of a pressure-swirl nozzle
Sapík, Marcel ; Pech, Ondřej (referee) ; Jedelský, Jan (advisor)
The aim of the thesis is to put a transparent scaled PMMA model of the pressure swirl nozzle into operation, which includes, the selection of working fluids and the preparation of a test set to allow measurements using optical methods (LDA, PDA, PIV, high-speed visualization). The theoretical part describes the basic theory of atomization, optical measurement methods and deals with the problems of optical transition in optically complex systems. It also includes an extensive search for transparent liquids and materials of enlarged models that have been used in experiments, which often aim to match light refractive indices between these materials. In the practical part, attention is paid to the preparation of the test set and tests of chemical effects of several selected liquids on PMMA material are conducted, including a summary of experience with their use, as there was a permanent damage to the material. Several LDA measurements followed, using kerosene, p-cymene, 1-bromonaphthalene and water, evaluated the effect of the refractive index difference on the results. It turned out that no observable influence occurred if the refractive index difference between the nozzle material and the liquid was small. In addition, a visualization of internal flow through a high-speed camera was made. The practical part closes the static pressure measurement in the nozzle chamber, where the pressure ratio was measured on the walls of the chamber as well as on its axis. The measurement confirmed that the pressure on the chamber walls is constant and varies with the distance from the chamber axis.
|
|
|
Influence of manufacturing process and precision on quality of liquid atomization from pressure-swirl atomizers
Lebeda, Kryštof ; Cejpek, Ondřej (referee) ; Malý, Milan (advisor)
The thesis deals with the effects of manufacturing inaccuracies and manufacturing method on the spray quality of pressure-swirl atomizers. First, basic principles of atomization are outlined. In the next section, observed atomization parameters of pressure swirl atomizers are discussed. This is followed by a research of available studies investigating influence of inaccuracies and manufacturing methods on selected parameters. In the practical part evaluation of measured data of pressure-swirl atomizers with defects at discharge orifice, different surface roughness and atomizers made by 3D printing was carried out. Skewness and misalignment of discharge orifice significantly reduced spray quality. No effect of surface roughness for conventionally manufactured nozzles was found. The use of 3D printing for nozzle production resulted in a deterioration of atomization fineness. Chamfering of dicharge orifice promoted larger spray cone angle but did not affect the atomization fineness.
|
|
|
Testing of a transparent model of a pressure-swirl nozzle
Sapík, Marcel ; Pech, Ondřej (referee) ; Jedelský, Jan (advisor)
The aim of the thesis is to put a transparent scaled PMMA model of the pressure swirl nozzle into operation, which includes, the selection of working fluids and the preparation of a test set to allow measurements using optical methods (LDA, PDA, PIV, high-speed visualization). The theoretical part describes the basic theory of atomization, optical measurement methods and deals with the problems of optical transition in optically complex systems. It also includes an extensive search for transparent liquids and materials of enlarged models that have been used in experiments, which often aim to match light refractive indices between these materials. In the practical part, attention is paid to the preparation of the test set and tests of chemical effects of several selected liquids on PMMA material are conducted, including a summary of experience with their use, as there was a permanent damage to the material. Several LDA measurements followed, using kerosene, p-cymene, 1-bromonaphthalene and water, evaluated the effect of the refractive index difference on the results. It turned out that no observable influence occurred if the refractive index difference between the nozzle material and the liquid was small. In addition, a visualization of internal flow through a high-speed camera was made. The practical part closes the static pressure measurement in the nozzle chamber, where the pressure ratio was measured on the walls of the chamber as well as on its axis. The measurement confirmed that the pressure on the chamber walls is constant and varies with the distance from the chamber axis.
|
|
|
Atomization mechanisms of liquid fuels
Buzík, Jiří ; Bělohradský, Petr (referee) ; Broukal, Jakub (advisor)
The bachelor thesis deals with the atomization of liquid fuels and their atomizers and mechanisms which are concerned in atomization. The main purpose of this thesis is to describe the problems that are connected with the atomization. The author gives information about the primary and secondary decomposition of liquid. One part of the thesis is the software which focuses on the statistic evaluation and comparison of information which are performed by available experiments and numeric calculations.
|
|
| |
|
| |
|
| |
|
| |
guest ::
