Matches in SemOpenAlex for { <https://semopenalex.org/work/W1892497210> ?p ?o ?g. }
Showing items 1 to 83 of
83
with 100 items per page.
- W1892497210 abstract "The introduction of a gas into a liquid occurs in many chemical and biological engineering processes whichrequire a chemical or biological reaction to occur. In the case of aeration, air is introduced into water. Theaim of this thesis is to investigate the use of a novel venturi technology, termed the insert that can alleviatethe problems of existing technologies such as, restricted depth of use, mechanical wear and failure due tothe moving parts and problems with clogging and fouling, whilst providing high aeration efficiency.The inserts tested comprise of a central hub surrounded by a number of aerofoil shaped vanes, which haveair orifices located on their surfaces. The vanes create a number of discrete channels, which separate theflow and each channel is representative of a venturi. Three inserts and a regular venturi were tested. Theinserts had different angles of attack and a blockage ratio of either 1.5 or 4. Three orientations of the airorifices with respect to the vanes were considered. All inserts were compared to a regular venturi ofblockage ratio 1.5, which was made to British Standard 5167-4:2003.Two flow regimes were identified. The first is when a bubbly flow exists throughout the entire length of thedowncomer. The second is when a large ventilated cavity forms at the point of air injection, which is typicalat low water and higher air flow rates and was more prominent with the lower blockage ratio inserts. Theventilated cavity was seen to have a negative effect in terms of bubble size, specific power and masstransfer performance. The results show that the bubble size produced depends on the air and water flowrates, the flow regime and the insert design. The average bubble size at fixed flow rates is essentially thesame (differences within ± 10 %), when a ventilated cavity is present. However, when a full bubbly flow ispresent throughout the downcomer there were smaller average bubble sizes. Also inducing a swirl incombination with a high blockage ratio resulted in coring of the air at the higher flow rates. Reducing the airto water velocity slip ratio at the throat, by increasing the blockage ratio and the amount of air orifices,reduces the length of a ventilated cavity.This study also examines the hydrodynamic and mass transfer characteristics of the inserts. The insertswere tested in a laboratory scale experimental setup within a 100 mm ID pipe, where they were locatedabove the liquid surface. The results show that increasing the blockage ratio of the insert promoted asmaller mean bubble size, resulting in an increased mass transfer rate. However, the increased blockageratio results in significantly higher specific power consumption. The effect of insert design on the volumetricmass transfer coefficient was measured using a dynamic method outlined in the ASCE standard ASCE/EWRI2-06. The results confirmed that a reduced bubble size had a superior performance. The mass transfercoefficient is observed to be up to 50 % larger with a higher blockage ratio at higher flow rates.Computational fluid dynamic simulations are validated against the laboratory scale experimentation toAbstractiiidetermine the average bubble size, specific power consumption and the mass transfer coefficient, whichwere found to be within 6, 15 and 25 % of the laboratory scale values respectively. In addition to with thesevalidated models, geometric scaling was investigated for the one of the inserts, where it was geometricallyscaled from 100 mm to 190 mm ID. It was found that the geometrically scaled insert had an increasedSauter mean bubble size of 18.6 %, an increased pressure loss of 14.5 % and increased specific powerconsumption of 18.5 %.Along with the laboratory scale experimental work, hydrodynamic and mass transfer testing was conductedon high strength wastewater and clean water with an insert geometrically scaled up to 150 and 190 mmrespectively. A number of key parameters were seen to affect the system performance, including thephysical properties of the water, such as dissolved solids, the upstream geometry and mixture outlet.In conclusion it was found that the inserts in this experimental work have an improved aerationperformance in comparison to the regular venturi, at the lower air and water flow rates. However, abovethese lower flow rates, the regular venturi has the best aeration performance. Areas for improvement havehowever been identified for the inserts, such as decreasing the air to water velocity slip ratio at the throat,where the performance of the redesigned insert can successfully be investigated using CFD simulations." @default.
- W1892497210 created "2016-06-24" @default.
- W1892497210 creator A5054814429 @default.
- W1892497210 date "2013-01-01" @default.
- W1892497210 modified "2023-09-26" @default.
- W1892497210 title "Novel venturi technology for the purpose of gas-liquid mass transfer" @default.
- W1892497210 hasPublicationYear "2013" @default.
- W1892497210 type Work @default.
- W1892497210 sameAs 1892497210 @default.
- W1892497210 citedByCount "0" @default.
- W1892497210 crossrefType "dissertation" @default.
- W1892497210 hasAuthorship W1892497210A5054814429 @default.
- W1892497210 hasConcept C115792997 @default.
- W1892497210 hasConcept C121332964 @default.
- W1892497210 hasConcept C127413603 @default.
- W1892497210 hasConcept C166957645 @default.
- W1892497210 hasConcept C185592680 @default.
- W1892497210 hasConcept C192562407 @default.
- W1892497210 hasConcept C194242075 @default.
- W1892497210 hasConcept C201289731 @default.
- W1892497210 hasConcept C21423434 @default.
- W1892497210 hasConcept C23795335 @default.
- W1892497210 hasConcept C2778152828 @default.
- W1892497210 hasConcept C38349280 @default.
- W1892497210 hasConcept C41625074 @default.
- W1892497210 hasConcept C51038369 @default.
- W1892497210 hasConcept C548081761 @default.
- W1892497210 hasConcept C55493867 @default.
- W1892497210 hasConcept C57879066 @default.
- W1892497210 hasConcept C78519656 @default.
- W1892497210 hasConcept C78762247 @default.
- W1892497210 hasConcept C81862102 @default.
- W1892497210 hasConcept C86922832 @default.
- W1892497210 hasConcept C95457728 @default.
- W1892497210 hasConceptScore W1892497210C115792997 @default.
- W1892497210 hasConceptScore W1892497210C121332964 @default.
- W1892497210 hasConceptScore W1892497210C127413603 @default.
- W1892497210 hasConceptScore W1892497210C166957645 @default.
- W1892497210 hasConceptScore W1892497210C185592680 @default.
- W1892497210 hasConceptScore W1892497210C192562407 @default.
- W1892497210 hasConceptScore W1892497210C194242075 @default.
- W1892497210 hasConceptScore W1892497210C201289731 @default.
- W1892497210 hasConceptScore W1892497210C21423434 @default.
- W1892497210 hasConceptScore W1892497210C23795335 @default.
- W1892497210 hasConceptScore W1892497210C2778152828 @default.
- W1892497210 hasConceptScore W1892497210C38349280 @default.
- W1892497210 hasConceptScore W1892497210C41625074 @default.
- W1892497210 hasConceptScore W1892497210C51038369 @default.
- W1892497210 hasConceptScore W1892497210C548081761 @default.
- W1892497210 hasConceptScore W1892497210C55493867 @default.
- W1892497210 hasConceptScore W1892497210C57879066 @default.
- W1892497210 hasConceptScore W1892497210C78519656 @default.
- W1892497210 hasConceptScore W1892497210C78762247 @default.
- W1892497210 hasConceptScore W1892497210C81862102 @default.
- W1892497210 hasConceptScore W1892497210C86922832 @default.
- W1892497210 hasConceptScore W1892497210C95457728 @default.
- W1892497210 hasLocation W18924972101 @default.
- W1892497210 hasOpenAccess W1892497210 @default.
- W1892497210 hasPrimaryLocation W18924972101 @default.
- W1892497210 hasRelatedWork W109655941 @default.
- W1892497210 hasRelatedWork W1985214611 @default.
- W1892497210 hasRelatedWork W1998103094 @default.
- W1892497210 hasRelatedWork W2009181505 @default.
- W1892497210 hasRelatedWork W2021780230 @default.
- W1892497210 hasRelatedWork W2034412313 @default.
- W1892497210 hasRelatedWork W2045323423 @default.
- W1892497210 hasRelatedWork W2052305792 @default.
- W1892497210 hasRelatedWork W2061754538 @default.
- W1892497210 hasRelatedWork W2066715502 @default.
- W1892497210 hasRelatedWork W2091093390 @default.
- W1892497210 hasRelatedWork W2104129254 @default.
- W1892497210 hasRelatedWork W2343085314 @default.
- W1892497210 hasRelatedWork W2372708383 @default.
- W1892497210 hasRelatedWork W2522620980 @default.
- W1892497210 hasRelatedWork W2554796896 @default.
- W1892497210 hasRelatedWork W2606897005 @default.
- W1892497210 hasRelatedWork W2899298469 @default.
- W1892497210 hasRelatedWork W3127049455 @default.
- W1892497210 hasRelatedWork W3170502497 @default.
- W1892497210 isParatext "false" @default.
- W1892497210 isRetracted "false" @default.
- W1892497210 magId "1892497210" @default.
- W1892497210 workType "dissertation" @default.