|
|
Fluid flow in narrow gap between two cylinders induced by pressure gradient
Bartková, Tamara ; Štefan, David (referee) ; Štigler, Jaroslav (advisor)
Diplomová práca je zameraná na popísanie prúdenia tekutiny medzikruhovým potrubím. Tok tekutiny je skúmaný pri viacerých podmienkach, čo vedie k laminárnemu ale aj turbulentnému prúdeniu. Práca obsahuje rešeršnú časť, ktorá opisuje doteraz známe vzťahy popisujúce daný typ prúdenia a takisto skúma spôsoby merania rýchlostného profilu v medzikruhových medzerách. Nasledujúca časť obsahuje návrh výpočtového modelu, popis simulácií prúdenia pri konkrétnych podmienkach a ich vyhodnotenie. Výsledky zo simulačnej časti sú použité pri popise charakteristických vlastností turbulentného prúdenia v medzikruží. Tieto charakteristiky sú použité v ďalšej časti práce, ktorá je cielená na získanie analytického vzťahu, ktorý by popisoval časovo stredovaný rýchlostný profil turbulentného prúdenia v medzikruhovej medzere.
|
|
|
The second phase shifting I/9 Dubice - Dolni Libchava
Belda, Miroslav ; Jíra, Daniel (referee) ; Kosňovský, Michal (advisor)
Master's thesis will deal with the second phase of shifting I/9 Dubice - Dolni Libchava passing west of the Ceska Lipa with an approximate length of 3 km stretch. Estimated start-up of this section is in 2014. This project should build on in the future by-pass Ceska Lipa and Novy Bor, which is currently without funds for implementation by 2025. Traffic load after completion of the by-pass should be approximately 16500 vehicles / 24 hours in 2030. The section is designed in the category S 9.5 with optional solving two major intersections. This thesis will focus on reducing the cost of construction of the section.
|
|
|
Critical Heat Flux on Smooth and Modified Surfaces
Suk, Ladislav ; Kolat, Pavel (referee) ; Katovský, Karel (referee) ; Fiedler, Jan (advisor)
This thesis deals with the problem of critical heat flux (CHF) on technically smooth and treated surfaces at low pressures. The theoretical part presents the basic concepts of two-phase flow and an analysis of existing work on the influence of the surface on CHF. The main part of the work describes the built experimental apparatus for CHF research at low pressures of 100 -1500 kPa (1-15 bar) with a vertical internally heated annular test section. The internal annuli consists of an outer glass tube with an inner diameter of 14.8 mm and an inner tube made of Inconel ™ 625 / Optimized ZIRLO ™ with an outer diameter of 9.14 mm and a heated length of 380/365 mm. CHF experiments on technically smooth surface were performed at outlet pressures 120 kPa, 200 kPa and 300 kPa, at an inlet temperature of 64, 78 and 91 °C and at mass flux of 400, 500, 600 and 800 kg / m2s. The Inconel tubes were tested in two different surface modifications - abraded and bead blasted. Experiments were performed at mass flows of 400, 500 and 600 kg / m2s. The total number of 122 experimental runs were conducted and the results were compared with other literature experimental data. The maximum increase of CHF on abraded / bead blasted tube was 18.12% / 16.17%. The surface structure was analysed by laser microscopy. The wetting behaviour of the surface structures was measured by the sessile drop method. The elemental analysis of the surface was evaluated using the EDS method.
|
|
|
Critical Heat Flux on Smooth and Modified Surfaces
Suk, Ladislav ; Kolat, Pavel (referee) ; Katovský, Karel (referee) ; Fiedler, Jan (advisor)
This thesis deals with the problem of critical heat flux (CHF) on technically smooth and treated surfaces at low pressures. The theoretical part presents the basic concepts of two-phase flow and an analysis of existing work on the influence of the surface on CHF. The main part of the work describes the built experimental apparatus for CHF research at low pressures of 100 -1500 kPa (1-15 bar) with a vertical internally heated annular test section. The internal annuli consists of an outer glass tube with an inner diameter of 14.8 mm and an inner tube made of Inconel ™ 625 / Optimized ZIRLO ™ with an outer diameter of 9.14 mm and a heated length of 380/365 mm. CHF experiments on technically smooth surface were performed at outlet pressures 120 kPa, 200 kPa and 300 kPa, at an inlet temperature of 64, 78 and 91 °C and at mass flux of 400, 500, 600 and 800 kg / m2s. The Inconel tubes were tested in two different surface modifications - abraded and bead blasted. Experiments were performed at mass flows of 400, 500 and 600 kg / m2s. The total number of 122 experimental runs were conducted and the results were compared with other literature experimental data. The maximum increase of CHF on abraded / bead blasted tube was 18.12% / 16.17%. The surface structure was analysed by laser microscopy. The wetting behaviour of the surface structures was measured by the sessile drop method. The elemental analysis of the surface was evaluated using the EDS method.
|
|
|
Fluid flow in narrow gap between two cylinders induced by pressure gradient
Bartková, Tamara ; Štefan, David (referee) ; Štigler, Jaroslav (advisor)
Diplomová práca je zameraná na popísanie prúdenia tekutiny medzikruhovým potrubím. Tok tekutiny je skúmaný pri viacerých podmienkach, čo vedie k laminárnemu ale aj turbulentnému prúdeniu. Práca obsahuje rešeršnú časť, ktorá opisuje doteraz známe vzťahy popisujúce daný typ prúdenia a takisto skúma spôsoby merania rýchlostného profilu v medzikruhových medzerách. Nasledujúca časť obsahuje návrh výpočtového modelu, popis simulácií prúdenia pri konkrétnych podmienkach a ich vyhodnotenie. Výsledky zo simulačnej časti sú použité pri popise charakteristických vlastností turbulentného prúdenia v medzikruží. Tieto charakteristiky sú použité v ďalšej časti práce, ktorá je cielená na získanie analytického vzťahu, ktorý by popisoval časovo stredovaný rýchlostný profil turbulentného prúdenia v medzikruhovej medzere.
|
|
|
The second phase shifting I/9 Dubice - Dolni Libchava
Belda, Miroslav ; Jíra, Daniel (referee) ; Kosňovský, Michal (advisor)
Master's thesis will deal with the second phase of shifting I/9 Dubice - Dolni Libchava passing west of the Ceska Lipa with an approximate length of 3 km stretch. Estimated start-up of this section is in 2014. This project should build on in the future by-pass Ceska Lipa and Novy Bor, which is currently without funds for implementation by 2025. Traffic load after completion of the by-pass should be approximately 16500 vehicles / 24 hours in 2030. The section is designed in the category S 9.5 with optional solving two major intersections. This thesis will focus on reducing the cost of construction of the section.
|
|
|
Určení objemového průtoku vazkoplastických kapalin mezikružím za pomoci aditivní metody
Filip, Petr ; David, Jiří
An additive method enabling a direct determination of axial flow rate for viscous (power-law model) and viscoplastic (Vočadlo model) fluids in concentric annuli is presented. Flow rate through the actual concentric annulus is possible to express as a sum of axial flow rates through individual partial concentric annuli forming the whole annulus. The resulting relation for axial flow rate is possible to express in analytical forms without necessity of otherwise complicated derivations. The only numerical calculation consists in a determination of location of a zero shear stress for the original whole concentric annulus.
|
guest ::
