INFLUENCE OF IMPELLER SUCTION SPECIFIC SPEED ON VIBRATION PERFORMANCE

LectureThe most commonly used hard limitation for pump suction specific speed is 11,000 (US units). This hard limit grew out of the recommendations from a 1982 reliability study by J.L. Hallam (Hallam 1982). Concomitant testing of the vibration performance of an OH2 4x6-11 pump was made with impellers designed for different suction specific speeds (Lobanoff and Ross 1985). This study showed that all things being equal, a strong relationship existed between suction specific speed and the pump vibration at off BEP operation. Given the significant changes in impeller design methods and computational tools in the subsequent three decades, this paper seeks to investigate how these new methods/tools have affected the relationship between suction specific speed and the pump vibration. 3rd Middle East Turbomachinery Symposium (METS III) 15-18 February 2015 | Doha, Qatar | mets.tamu.edu Copyright© 2015 by Turbomachinery Laboratory, Texas A&M Engineering Experiment Station 2 Experiments are performed using a series of impellers designed for different suction specific speeds using modern design techniques. These impellers are mounted in a subject test pump which is also an OH2 4x6-11 in order to achieve equivalency with the prior testing. Vibration performance over the pump operating range is recorded. The results are complemented with computational fluid dynamic (CFD) analysis to further examine the performance of each impeller

An enhanced fresh cadaveric model for reconstructive microsurgery training

Open access via Springer Compact Acknowledgements The generosity of the people of the North East of Scotland who donated their bodies to the University of Aberdeen for anatomical study is recognised. Their contribution is appreciated and valued. Funding The authors received no financial support for the research, authorship, and/or publication of this article.Peer reviewedPublisher PD

Modification Of Bb1 Pump Vibration Characteristics To Meet ISO 13709 2nd Edition (API 610 11th) Limits

Case Stud

Cuprate addition to a 6-substituted pentafulvene: preparation of sec-alkyl substituted titanocene dichlorides and their biological activity

The copper-catalysed (10 mol-% CuBr·SMe2, CuCN·LiCl or CuI/PPh3) addition of RMgBr to the pentafulvene 1-(cyclopenta-2,4-dien-1-ylidenemethyl)-2-methoxybenzene allows the formation of cyclopentadienyl derivatives with α-CHR(2-MeOPh) sidechains (R = Me, Et, nBu, iBu, allyl, Ph) without H– transfer. The deprotonation of these sec-alkyl-substituted cyclopentadienyls followed by the addition of TiCl4 allows the isolation of TiCl2{η5-C5H4CHR(2-OMePh)} as rac/meso mixtures that show activity against human colon, breast and pancreatic cell lines (GI50 2.3–42.4 μM)

Report on shopper travel behaviour in Dublin City Centre

Traders on Dublin’s two main shopping streets considerably over-estimate spending by shoppers travelling by car and Luas while significantly undervaluing the spend of bus passengers and pedestrians. A study interviewed 1,009 shoppers on Grafton and Henry streets seeking to identify differences (if any) between perceived and actual spending levels by travel mode. Bus carried 35% of shoppers to Grafton St and 49% to Henry St; this compares with traders’ perceptions of 31% and 40% respectively. Measured in value terms, bus proved the most lucrative mode to both streets, delivering 38% of the total spend on both streets, when outliers are excluded. Pedestrian travel was similarly under-valued. Traders believed that 11% would walk to shop on Grafton St while on Henry St traders estimated that 6% of their customers came on foot. The actual figures are 20% and 19%, according to the survey. Car transport was overvalued by traders. On Grafton St traders perceived that car would account for 13% of customers whereas in reality car-borne shoppers made up 10%. Traders on Henry St believed car would carry 19% of shoppers but in fact only 9% came by car. The situation is similar for Luas: traders perceived 28% of Grafton St shoppers would arrive by tram compared to 13% in reality, and again on Henry St, traders thought Luas would carry 19% but it served just 10%. Bus priority and pedestrian enhancement may therefore warrant greater investment. The imbalance in cycling mode share between Grafton Street and Henry Street should also be investigated further

Modification Of The Bb1 Pump Vibration Characteristics To Meet ISO 13709

Case Stud

Calling time: How to remove fossil fuel sponsorships from sports, arts & events

Sports, arts and major events are deeply embedded in the Australian way of life. Weekend matches, concerts and festivals bring us together - to cheer, to share pride and excitement, to feel connected to each other and to keep building our national story. When we barrack for our beloved teams, discover the work of a new local artist or laugh until our cheeks hurt at a comedy show, we are taking part in a ritual that has shaped social and cultural life in Australia for generations. Climate change – driven by burning coal, oil and gas – is putting all of this at risk. From flooded festivals, to concerts cancelled by bushfire threats and unsafe heat disrupting play at the tennis, footy and more, climate change is wreaking havoc on the activities and events we love..

Making the journey with me : a qualitative study of experiences of a bespoke mental health smoking cessation intervention for service users with serious mental illness

BACKGROUND: Smoking is one of the major modifiable risk factors contributing to early mortality for people with serious mental illness. However, only a minority of service users access smoking cessation interventions and there are concerns about the appropriateness of generic stop-smoking services for this group. The SCIMITAR (Smoking Cessation Intervention for Severe Mental Ill-Health Trial) feasibility study explored the effectiveness of a bespoke smoking cessation intervention delivered by mental health workers. This paper reports on the nested qualitative study within the trial. METHODS: Qualitative semi-structured interviews were conducted with 13 service users receiving the intervention and 3 of the MHSCPs (mental health smoking cessation practitioners) delivering the intervention. Topic guides explored the perceived acceptability of the intervention particularly in contrast to generic stop-smoking services, and perceptions of the implementation of the intervention in practice. Transcripts were analysed using the Constant Comparative Method. RESULTS: Generic services were reported to be inappropriate for this group, due to concerns over stigma and a lack of support from health professionals. The bespoke intervention was perceived positively, with both practitioners and service users emphasising the benefits of flexibility and personalisation in delivery. The mental health background of the practitioners was considered valuable not only due to their increased understanding of the service users' illness but also due to the more collaborative relationship style they employed. Challenges involved delays in liaising with general practitioners and patient struggles with organisation and motivation, however the MHSCP was considered to be well placed to address these problems. CONCLUSION: The bespoke smoking cessation intervention was acceptable to service users and the both service users and practitioners reported the value of a protected mental health worker role for delivering smoking cessation to this group. The results have wider implications for understanding how to achieve integrated and personalised care for this high-risk population and further underscore the need for sensitised smoking cessation support for people with serious mental illness. TRIAL REGISTRATION: Current Controlled Trials ISRCTN79497236 . Registered 3(rd) July 2009