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Truck oil cooler
Pobořil, Martin ; Krištof, Ondřej (referee) ; Bartuli, Erik (advisor)
This diploma thesis deals with designing, fabrication and testing of transmission oil cooler of a truck made of polymeric hollow fibers. Literary research was done in the field of currently used vehicle gearboxes. An overview of properties and a distribution of oils was presented. Oils perform mainly lubricating, hydraulic and cooling function in the gearbox. The thesis contains a design of a cooler according to the specified parameters and its manufacturing process which was done by fiber winding technology. The device X-Winder was used. The program controlling all movements of the machine was programmed. The manufactured cooler passed tear tests and a measurement of characteristic parameters was taken. The pressure drop in fibers was measured at 80 °C . The aim of measurement at 60 and 70 °C was to get a pressure drop in shell and a thermal performance of the cooler. It was found out that the pressure drop dependence on a the shell flow is almost identical for both temperatures, which implies that the effect of the temperature on the pressure drop is negligible. The measurement of thermal performance was done under the same conditions as the measurement of the shell pressure drop. Its maximum achieved reading was 4,8 kW, at shell flow 100 liters per hour and at the temperature 59 °C. The achieved thermal performance is comparable to the thermal performance of standard metal coolers.
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Racing vehicle engine oil cooler
Lang, Filip ; Guzej, Michal (referee) ; Bartuli, Erik (advisor)
This disertation is about designing an oil cooler for racing car made of polymer hollow fibers. The oil cooler was made on an X-Winder device, which is not originally designed for production of heat exchangers, which was quite complicated to produce these exchangers. Therefore, programs initiating the movement of the winding device based on the parameters entered by the user were created within the work. The manufactured cooler was compared with used oil cooler from the race car in pursuance of measured parameters in the experimental chamber.
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Mathematical Model of Membrane Distillation
Hvožďa, Jiří ; Komínek, Jan (referee) ; Kůdelová, Tereza (advisor)
Diplomová práce se zabývá membránovou destilací, především z matematické perspektivy. Jedná se o tepelně poháněný separační proces, ve kterém se pro rozdělení kapalné a plynné fáze používá porézní membrána. Kapalina se vypařuje a její plynná fáze prochází přes póry v membráně. Během tohoto procesu dochází k tepelné i látkové výměně, které jsou popsány systémem parciálních diferenciálnich rovnic. Další model je založen na analogii s elektrickými obvody, zákonu zachování energie, hmotnostní bilanci a empirických vztazích. Je ověřen s experimentálně naměřenými daty z nové alternativní destilační jednotky používající membránu a kondenzátor z polymerních dutých vláken. Výkon a účinnost jednotky jsou vyhodnoceny. Další možná vylepšení jsou navržena.
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Polymeric Hollow Fiber Heat Exchanger Design
Astrouski, Ilya ; Dohnal, Mirko (referee) ; Horák, Aleš (referee) ; Raudenský, Miroslav (advisor)
This Ph.D. thesis is focused on theory and experimental investigations developing of new knowledge about polymeric hollow fiber heat exchanger (PHFHE). The state-of-the-art study of plastic heat exchangers shows that their usage is limited by several niches where their advantages significantly dominates, or where the use of non-plastic competitors is not impossible. On the other hand, plastic heat exchangers (and PHFHEs in particular) are devices of increasing interest. It is shown that use of small tubes (fibers) allows PHFHEs to be more competitive than conventional plastic heat exchangers. Small hydraulic diameter of a fiber causes high heat transfer coefficients, reduces thermal resistance of plastic wall and allows it to create light and compact design. Detailed study of fluid flow and heat transfer inside the hollow fiber showed that conventional approaches for single-phase laminar flow can be utilized. Poiseuille number equal to 64 and Nussel number about 4 are recommended to be used to predict pressure drops and heat transfer coefficient, respectively. Additional attention should be paid to careful determination of fiber diameter and liquid properties (viscosity). Scaling effects, such as axial heat conduction, thermal entrance region and viscous dissipation can be neglected. The study of outside heat transfer showed that heat transfer on fiber bunches are intense and are competitive to contemporary compact finned-tube heat exchangers. The Grimson approach showed clear correlation with experimental results and, thus is recommended to predict heat transfer coefficients on fiber bunches. Two types of fouling (particulate- and biofouling) of outer fiber surface were experimentally studied. It was found that particulate fouling by titanium oxide particles is not intense and deposits can be removed relatively easy. However, fouling is much more intense when it is associated with biofouling caused by wastewater. In this case, smooth and low-adhesive surface of plastic is not sufficient precaution to prevent deposit formation.
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Truck oil cooler
Pobořil, Martin ; Krištof, Ondřej (referee) ; Bartuli, Erik (advisor)
This diploma thesis deals with designing, fabrication and testing of transmission oil cooler of a truck made of polymeric hollow fibers. Literary research was done in the field of currently used vehicle gearboxes. An overview of properties and a distribution of oils was presented. Oils perform mainly lubricating, hydraulic and cooling function in the gearbox. The thesis contains a design of a cooler according to the specified parameters and its manufacturing process which was done by fiber winding technology. The device X-Winder was used. The program controlling all movements of the machine was programmed. The manufactured cooler passed tear tests and a measurement of characteristic parameters was taken. The pressure drop in fibers was measured at 80 °C . The aim of measurement at 60 and 70 °C was to get a pressure drop in shell and a thermal performance of the cooler. It was found out that the pressure drop dependence on a the shell flow is almost identical for both temperatures, which implies that the effect of the temperature on the pressure drop is negligible. The measurement of thermal performance was done under the same conditions as the measurement of the shell pressure drop. Its maximum achieved reading was 4,8 kW, at shell flow 100 liters per hour and at the temperature 59 °C. The achieved thermal performance is comparable to the thermal performance of standard metal coolers.
|
|
|
Racing vehicle engine oil cooler
Lang, Filip ; Guzej, Michal (referee) ; Bartuli, Erik (advisor)
This disertation is about designing an oil cooler for racing car made of polymer hollow fibers. The oil cooler was made on an X-Winder device, which is not originally designed for production of heat exchangers, which was quite complicated to produce these exchangers. Therefore, programs initiating the movement of the winding device based on the parameters entered by the user were created within the work. The manufactured cooler was compared with used oil cooler from the race car in pursuance of measured parameters in the experimental chamber.
|
|
|
Mathematical Model of Membrane Distillation
Hvožďa, Jiří ; Komínek, Jan (referee) ; Kůdelová, Tereza (advisor)
Diplomová práce se zabývá membránovou destilací, především z matematické perspektivy. Jedná se o tepelně poháněný separační proces, ve kterém se pro rozdělení kapalné a plynné fáze používá porézní membrána. Kapalina se vypařuje a její plynná fáze prochází přes póry v membráně. Během tohoto procesu dochází k tepelné i látkové výměně, které jsou popsány systémem parciálních diferenciálnich rovnic. Další model je založen na analogii s elektrickými obvody, zákonu zachování energie, hmotnostní bilanci a empirických vztazích. Je ověřen s experimentálně naměřenými daty z nové alternativní destilační jednotky používající membránu a kondenzátor z polymerních dutých vláken. Výkon a účinnost jednotky jsou vyhodnoceny. Další možná vylepšení jsou navržena.
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|
|
Polymeric Hollow Fiber Heat Exchanger Design
Astrouski, Ilya ; Dohnal, Mirko (referee) ; Horák, Aleš (referee) ; Raudenský, Miroslav (advisor)
This Ph.D. thesis is focused on theory and experimental investigations developing of new knowledge about polymeric hollow fiber heat exchanger (PHFHE). The state-of-the-art study of plastic heat exchangers shows that their usage is limited by several niches where their advantages significantly dominates, or where the use of non-plastic competitors is not impossible. On the other hand, plastic heat exchangers (and PHFHEs in particular) are devices of increasing interest. It is shown that use of small tubes (fibers) allows PHFHEs to be more competitive than conventional plastic heat exchangers. Small hydraulic diameter of a fiber causes high heat transfer coefficients, reduces thermal resistance of plastic wall and allows it to create light and compact design. Detailed study of fluid flow and heat transfer inside the hollow fiber showed that conventional approaches for single-phase laminar flow can be utilized. Poiseuille number equal to 64 and Nussel number about 4 are recommended to be used to predict pressure drops and heat transfer coefficient, respectively. Additional attention should be paid to careful determination of fiber diameter and liquid properties (viscosity). Scaling effects, such as axial heat conduction, thermal entrance region and viscous dissipation can be neglected. The study of outside heat transfer showed that heat transfer on fiber bunches are intense and are competitive to contemporary compact finned-tube heat exchangers. The Grimson approach showed clear correlation with experimental results and, thus is recommended to predict heat transfer coefficients on fiber bunches. Two types of fouling (particulate- and biofouling) of outer fiber surface were experimentally studied. It was found that particulate fouling by titanium oxide particles is not intense and deposits can be removed relatively easy. However, fouling is much more intense when it is associated with biofouling caused by wastewater. In this case, smooth and low-adhesive surface of plastic is not sufficient precaution to prevent deposit formation.
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