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Charge Efficiency of a Gasoline Turbocharged Engine
Holas, Tomáš ; Böhm, Michael (referee) ; Svída, David (advisor)
This bachelor thesis deals with the topic of volumetric efficiency of a gasoline turbocharged engine. The first part of this thesis is devoted to research on this topic. In the second part of the thesis an analysis of data from a 1.5 TSI engine from the Volkswagen group line-up obtained during the WLTP test was performed. This analysis was achieved by the means of creating regression models on the measured data and comparing their results. The result of this analysis was the determination of the main ordinarily measured parameters on which the volumetric efficiency depends.
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FLow in cracs
Ocásek, Adam ; Veselý, Jindřich (referee) ; Haluza, Miloslav (advisor)
This Master’s thesis investigates the flow in sealing gaps of impeller within pumps and turbines. Sealing gaps are installed to improve the volumetric efficiency in this type of fluid machinery. Despite present extensive research this subject has not been entirely documented and the thesis’ aim is to improve our knowledge in this matter. At the beginning, the practical experiment is used in order to establish appropriate numerical description of flow in seals and to calibrate software FLUENT. In chapter five, the thesis analyses the influence of seal design on volumetric efficiency of pumps and turbines and defines its optimal construction to improve the efficiency. The thesis then examines the effect of rotor eccentricity on flow properties, flow rate and pressure distribution within the sealing gap. In the last section, through chapters six to eight, the flow results provided by numerical solution in FLUENT and selected analytical equations, or their modified forms, are being discussed. The degree of correspondence between the results is also studied.
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Valveless Plunger Pump
Machů, Tomáš ; Kozubková, Milada (referee) ; Melichar, Jan (referee) ; Pochylý, František (advisor)
This thesis deals with valveless reciprocating pumps. Within the thesis several designs of pump geometry are demonstrated. Their parameters were obtained using computational fluid dynamics. Reciprocating piston movement was simulated by time dependent inlet boundary condition or by dynamic mesh. The individual variants were compared mainly from point of view of volumetric efficiency, which was the main evaluated parameter. Results of calculations are presented as dependencies of volumetric efficiency on frequency and amplitude of piston motion and on value of backpressure. Two variants of the prototype pump geometry were manufactured to experimentally validate parameters obtained from calculations. Volumetric efficiency together with hydraulic efficiency were evaluated from measured data.
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Volumetric losses
Feldová, Petra ; Sluše, Jan (referee) ; Klas, Roman (advisor)
The main goal of this bachelor thesis is to evaluate the flow of sealing gaps and assess the impact of the expansion chambers of various shapes , placing them in order to reduce volumetric losses . The first section summarizes theoretical knowledge of pumps, which suffer the most from these losses. There are also described the analytic solutions of flow in the cracks and possible use of simulation programs, such as Fluent, for investigation of more difficult tasks. The computational part compares analytically determined values of the volume flow for smooth gap, with the values obtained from the program Fluent. Thanks to the values from this program is also possible to assess the effect of rotation on the flows. Analytical relationships do not include this impact . For easier comparison the flow in the expansion chambers are further drawn contours of the static pressure, velocity vectors and pathlines in their cross-section.
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Charge Efficiency of a Gasoline Turbocharged Engine
Holas, Tomáš ; Böhm, Michael (referee) ; Svída, David (advisor)
This bachelor thesis deals with the topic of volumetric efficiency of a gasoline turbocharged engine. The first part of this thesis is devoted to research on this topic. In the second part of the thesis an analysis of data from a 1.5 TSI engine from the Volkswagen group line-up obtained during the WLTP test was performed. This analysis was achieved by the means of creating regression models on the measured data and comparing their results. The result of this analysis was the determination of the main ordinarily measured parameters on which the volumetric efficiency depends.
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Valveless Plunger Pump
Machů, Tomáš ; Kozubková, Milada (referee) ; Melichar, Jan (referee) ; Pochylý, František (advisor)
This thesis deals with valveless reciprocating pumps. Within the thesis several designs of pump geometry are demonstrated. Their parameters were obtained using computational fluid dynamics. Reciprocating piston movement was simulated by time dependent inlet boundary condition or by dynamic mesh. The individual variants were compared mainly from point of view of volumetric efficiency, which was the main evaluated parameter. Results of calculations are presented as dependencies of volumetric efficiency on frequency and amplitude of piston motion and on value of backpressure. Two variants of the prototype pump geometry were manufactured to experimentally validate parameters obtained from calculations. Volumetric efficiency together with hydraulic efficiency were evaluated from measured data.
|
|
|
Volumetric losses
Feldová, Petra ; Sluše, Jan (referee) ; Klas, Roman (advisor)
The main goal of this bachelor thesis is to evaluate the flow of sealing gaps and assess the impact of the expansion chambers of various shapes , placing them in order to reduce volumetric losses . The first section summarizes theoretical knowledge of pumps, which suffer the most from these losses. There are also described the analytic solutions of flow in the cracks and possible use of simulation programs, such as Fluent, for investigation of more difficult tasks. The computational part compares analytically determined values of the volume flow for smooth gap, with the values obtained from the program Fluent. Thanks to the values from this program is also possible to assess the effect of rotation on the flows. Analytical relationships do not include this impact . For easier comparison the flow in the expansion chambers are further drawn contours of the static pressure, velocity vectors and pathlines in their cross-section.
|
|
|
FLow in cracs
Ocásek, Adam ; Veselý, Jindřich (referee) ; Haluza, Miloslav (advisor)
This Master’s thesis investigates the flow in sealing gaps of impeller within pumps and turbines. Sealing gaps are installed to improve the volumetric efficiency in this type of fluid machinery. Despite present extensive research this subject has not been entirely documented and the thesis’ aim is to improve our knowledge in this matter. At the beginning, the practical experiment is used in order to establish appropriate numerical description of flow in seals and to calibrate software FLUENT. In chapter five, the thesis analyses the influence of seal design on volumetric efficiency of pumps and turbines and defines its optimal construction to improve the efficiency. The thesis then examines the effect of rotor eccentricity on flow properties, flow rate and pressure distribution within the sealing gap. In the last section, through chapters six to eight, the flow results provided by numerical solution in FLUENT and selected analytical equations, or their modified forms, are being discussed. The degree of correspondence between the results is also studied.
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