Effect of Shaft Diameter on the Hydrodynamic Torque of Butterfly Valve Disk.

J Fluids Eng

National-Provincial Joint Engineering Laboratory for Fluid Transmission System Technology, Zhejiang Sci-Tech University, 5 Second Avenue, Xiasha Higher Education Zone, Hangzhou, 310018, China.

Published: November 2020

In this study, computational fluid dynamics (cfd) software and detached eddy simulation turbulence model were used to simulate butterfly valves with different designs. The effects of shaft diameters on the value and the fluctuation of valve disk torque were studied, and the physical reason was discussed. The simulation results were verified by comparing with the experimental data. The findings revealed that with the closing of the valve, the hydraulic torque of the valve disk first increases and then decreases. Meanwhile, the torque decreases gradually with the increase of the shaft diameter. The variation of torque is caused by the change of pressure on both sides of the valve disk. The result also indicates that the fluctuation of torque is induced by the flow separation phenomenon occurs on the valve disk. The fluctuation is significant for the valve opening from 20% to 60%. The strength of the torque fluctuation is greater for the smaller shaft diameter. This study provides a theoretical basis for the design and optimization of butterfly valves.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7477715PMC
http://dx.doi.org/10.1115/1.4047795DOI Listing

Publication Analysis

Top Keywords

valve disk
20
shaft diameter
12
butterfly valves
8
fluctuation valve
8
torque
7
valve
7
disk
5
shaft
4
diameter hydrodynamic
4
hydrodynamic torque
4

Similar Publications

A rare case report of tissue infection caused by Pantoea piersonii (basionym Kalamiella piersonii).

Folia Microbiol (Praha)

October 2024

Clinic of Medical Microbiology, Gülhane Training and Research Hospital, University of Health Sciences, Ankara, 06010, Türkiye.

Article Synopsis
  • * Diagnosis can be tricky, as traditional methods may not accurately differentiate it from similar bacteria; advanced techniques like MALDI-TOF MS and genetic sequencing may be necessary for precise identification.
  • * A recent case report is the first to show P. piersonii isolated from a human tissue sample, emphasizing the importance of accurate identification and treatment, which led to the patient's recovery after appropriate antibiotic therapy.
View Article and Find Full Text PDF

Visual and surgical outcomes of childhood glaucoma following cataract surgery.

J AAPOS

October 2024

Division of Ophthalmology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois; Department of Ophthalmology, Northwestern University Feinberg School of Medicine, Chicago, Illinois. Electronic address:

Article Synopsis
  • The study aimed to assess how often patients with glaucoma following cataract surgery (GFCS) needed additional surgeries and their outcomes after treatment.
  • A review of medical records revealed that over half of the patients required glaucoma surgery, with those who had unilateral cataracts experiencing worse visual acuity compared to those with bilateral cataracts.
  • The findings indicated varying success rates for different surgical techniques, with Baerveldt implants performing the best in terms of long-term survival rates.
View Article and Find Full Text PDF

In this study, we established the control and design theory of an autonomously driven dispenser at a steady rotation speed and proposed a dispenser-integrated multiplex enzyme-linked immunosorbent assay (ELISA) device. In establishing the theory of the dispenser, we estimated the flow rate in the dispenser and the applied pressure onto the passive valves, so that the suitable burst pressure of the valves and flow rate could be designed. The dispenser-integrated multiplex ELISA device has the potential to perform flow control for executing an ELISA of 6 samples/standards per chip or 18 samples/standards per compact disk by just steadily rotating a chip.

View Article and Find Full Text PDF

Objectives: Patients receiving transcatheter aortic valve implantation (TAVI) are elderly with multiple comorbidities and at increased risk of perioperative cerebrovascular events. Retinal vasculature represents a surrogate of central nervous system circulation and is noninvasively achievable by retinal imaging. The aim of this study was to evaluate the applicability of retinal angiography of microvascular complications and association to cerebral ischemic events during TAVI.

View Article and Find Full Text PDF

Spatial contextual cues that help predict how a target will accelerate can be used to guide interception.

J Vis

October 2023

Department of Human Movement Sciences, Institute of Brain and Behavior Amsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.

Objects in one's environment do not always move at a constant velocity but often accelerate or decelerate. People are very poor at visually judging acceleration and normally make systematic errors when trying to intercept accelerating objects. If the acceleration is perpendicular to the direction of motion, it gives rise to a curved path.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!