{"id":{"repo_id":"freiburg-diss","oai_identifier":"oai:freidok.uni-freiburg.de:2096"},"canonical_url":"https://search.dev.ndltd.org/etd/freiburg-diss/oai:freidok.uni-freiburg.de:2096","repository":{"repo_id":"freiburg-diss","name":"University of Freiburg","base_url":"https://freidok.uni-freiburg.de/oai/oai2.php"},"display":{"title":"Development of an efficient 3-D CFD software to simulate and visualize the scavenging of a two-stroke engine","abstract":"The two-stroke engine is widely used in many different devices. But the environmentally problematic exhaust characteristic is a big drawback of this type of engine. In the scavenging process, when the fresh charge displaces the exhaust gas in the cylinder, lies the biggest opportunity to improve the exhaust data by geometry optimization. <br>Therefore, we developed a software package to efficiently simulate the three-dimensional, time-dependent, Navier-Stokes equations within the complex, real-world geometry of the two-stroke engine with moving piston and rotating crankshaft. Due to the high temperature in the cylinder after combustion, a temperature dependent treatment of the material constants is necessary. <br>Adaptive local time-stepping and dynamic local mesh adaption, as well as parallelization of the code, are used to speed up the computation time considerably. <br>The software has been extensively validated and has been applied to the problem of short-circuiting in two-stroke engines.","abstract_html":"The two-stroke engine is widely used in many different devices. But the environmentally problematic exhaust characteristic is a big drawback of this type of engine. In the scavenging process, when the fresh charge displaces the exhaust gas in the cylinder, lies the biggest opportunity to improve the exhaust data by geometry optimization. &lt;br&gt;Therefore, we developed a software package to efficiently simulate the three-dimensional, time-dependent, Navier-Stokes equations within the complex, real-world geometry of the two-stroke engine with moving piston and rotating crankshaft. Due to the high temperature in the cylinder after combustion, a temperature dependent treatment of the material constants is necessary. &lt;br&gt;Adaptive local time-stepping and dynamic local mesh adaption, as well as parallelization of the code, are used to speed up the computation time considerably. &lt;br&gt;The software has been extensively validated and has been applied to the problem of short-circuiting in two-stroke engines.","abstract_has_math":false,"creators":["Trescher, Dirk"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Kröner, Dietmar"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":null,"date_issued":"","date_published":null,"updated_at":"2026-07-24T02:22:33Z","subjects":["Adaptive Gitterverfeinerung","Lokale Zeitschrittweitenadaption","Temperaturabhängige Materialkonstanten","Relaxationsmethode","bewegte Gitter","Computational Fluid Dynamics","Two-Stroke Engine","Navier-Stoke Equations","Finite Volume Scheme","Moving Meshes"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://freidok.uni-freiburg.de/data/2096","outbound_label":"Repository record","outbound_source":"source_url"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Kröner, Dietmar"]},{"key":"dc:creator","label":"Author","values":["Trescher, Dirk"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:type","label":"Dc Type","values":["DoctoralThesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Adaptive Gitterverfeinerung","Lokale Zeitschrittweitenadaption","Temperaturabhängige Materialkonstanten","Relaxationsmethode","bewegte Gitter","Computational Fluid Dynamics","Two-Stroke Engine","Navier-Stoke Equations","Finite Volume Scheme","Moving Meshes"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The two-stroke engine is widely used in many different devices. But the environmentally problematic exhaust characteristic is a big drawback of this type of engine. In the scavenging process, when the fresh charge displaces the exhaust gas in the cylinder, lies the biggest opportunity to improve the exhaust data by geometry optimization. <br>Therefore, we developed a software package to efficiently simulate the three-dimensional, time-dependent, Navier-Stokes equations within the complex, real-world geometry of the two-stroke engine with moving piston and rotating crankshaft. Due to the high temperature in the cylinder after combustion, a temperature dependent treatment of the material constants is necessary. <br>Adaptive local time-stepping and dynamic local mesh adaption, as well as parallelization of the code, are used to speed up the computation time considerably. <br>The software has been extensively validated and has been applied to the problem of short-circuiting in two-stroke engines.","Der Zweitaktmotor wird in einer großen Anzahl von Geräten eingesetzt. Aber die umweltbelastenden Abgaswerte sind ein großer Nachteil von dieser Art Motor. Im Spülvorgang, bei dem das Frischgas das Abgas im Zylinder verdrängt, liegt die größte Möglichkeit, die Abgaswerte durch Geometrieoptimierung zu verbessern. <br>Daher haben wir ein Softwarepacket entwickelt, welches die dreidimensionalen zeitabhängigen Navier-Stokes Gleichungen in der komplexen realen Geometrie eines Zweitaktmotors mit sich bewegendem Kolben und rotierender Kurbelwelle effizient simuliert. Durch die hohen Temperaturen im Zylinder nach der Verbrennung wird eine temperaturabhängige Betrachtung der Materialkonstanten notwendig. <br>Adaptive lokale Zeitschrittweiten und dynamische lokale Gitteradaption, sowie eine Parallelisierung des Codes beschleunigen die Ausführungszeit erheblich. <br>Die Software wurde ausgiebig validiert und auf das Problem der Kurzschlussströmung eines Zweitaktmotores angewendet."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Development of an efficient 3-D CFD software to simulate and visualize the scavenging of a two-stroke engine","Entwicklung einer effizienten 3-D CFD Software zur Simulation und Visualisierung des Spülvorgangs eines Zweitaktmotors"]}]}],"canonical_facts":{"dc:contributor":["Kröner, Dietmar"],"dc:creator":["Trescher, Dirk"],"dc:description.abstract":["The two-stroke engine is widely used in many different devices. But the environmentally problematic exhaust characteristic is a big drawback of this type of engine. In the scavenging process, when the fresh charge displaces the exhaust gas in the cylinder, lies the biggest opportunity to improve the exhaust data by geometry optimization. <br>Therefore, we developed a software package to efficiently simulate the three-dimensional, time-dependent, Navier-Stokes equations within the complex, real-world geometry of the two-stroke engine with moving piston and rotating crankshaft. Due to the high temperature in the cylinder after combustion, a temperature dependent treatment of the material constants is necessary. <br>Adaptive local time-stepping and dynamic local mesh adaption, as well as parallelization of the code, are used to speed up the computation time considerably. <br>The software has been extensively validated and has been applied to the problem of short-circuiting in two-stroke engines.","Der Zweitaktmotor wird in einer großen Anzahl von Geräten eingesetzt. Aber die umweltbelastenden Abgaswerte sind ein großer Nachteil von dieser Art Motor. Im Spülvorgang, bei dem das Frischgas das Abgas im Zylinder verdrängt, liegt die größte Möglichkeit, die Abgaswerte durch Geometrieoptimierung zu verbessern. <br>Daher haben wir ein Softwarepacket entwickelt, welches die dreidimensionalen zeitabhängigen Navier-Stokes Gleichungen in der komplexen realen Geometrie eines Zweitaktmotors mit sich bewegendem Kolben und rotierender Kurbelwelle effizient simuliert. Durch die hohen Temperaturen im Zylinder nach der Verbrennung wird eine temperaturabhängige Betrachtung der Materialkonstanten notwendig. <br>Adaptive lokale Zeitschrittweiten und dynamische lokale Gitteradaption, sowie eine Parallelisierung des Codes beschleunigen die Ausführungszeit erheblich. <br>Die Software wurde ausgiebig validiert und auf das Problem der Kurzschlussströmung eines Zweitaktmotores angewendet."],"dc:format.medium":["application/pdf"],"dc:subject":["Adaptive Gitterverfeinerung","Lokale Zeitschrittweitenadaption","Temperaturabhängige Materialkonstanten","Relaxationsmethode","bewegte Gitter","Computational Fluid Dynamics","Two-Stroke Engine","Navier-Stoke Equations","Finite Volume Scheme","Moving Meshes"],"dc:title":["Development of an efficient 3-D CFD software to simulate and visualize the scavenging of a two-stroke engine","Entwicklung einer effizienten 3-D CFD Software zur Simulation und Visualisierung des Spülvorgangs eines Zweitaktmotors"],"dc:type":["DoctoralThesis"]},"updated_at":"2026-07-24T02:22:33Z"}