Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Steady Flow of a Fluid Stream01:27

Steady Flow of a Fluid Stream

878
Consider a control volume, such as a pipe with solid boundaries, through which fluid flows and changes direction due to the impulse exerted by the resulting force from the pipe walls. In steady flow, the mass of fluid entering the control volume at a given time, t, with velocity v1, is equal to the mass leaving after infinitesimal time dt, with velocity v2.
During this process, the momentum of the fluid within the control volume remains constant over the time interval dt. By applying the...
878
Laminar and Turbulent Flow01:07

Laminar and Turbulent Flow

12.0K
Fluid dynamics is the study of fluids in motion. Velocity vectors are often used to illustrate fluid motion in applications like meteorology. For example, wind—the fluid motion of air in the atmosphere—can be represented by vectors indicating the speed and direction of the wind at any given point on a map. Another method for representing fluid motion is a streamline. A streamline represents the path of a small volume of fluid as it flows. When the flow pattern changes with time, the...
12.0K
Conservation of Mass in Fixed, Nondeforming Control Volume01:07

Conservation of Mass in Fixed, Nondeforming Control Volume

1.7K
The principle of conservation of mass is fundamental in fluid dynamics and is crucial for analyzing flow within fixed control volumes, such as pipes or ducts. This principle states that the total mass within a control volume remains constant unless altered by the inflow or outflow of mass through the control surfaces. This results in a vital relationship for steady, incompressible flow where the mass entering a system equals the mass leaving it.
In the case of a sewer pipe, which can be modeled...
1.7K
Conservation of Mass in Finite Cotrol Volume01:16

Conservation of Mass in Finite Cotrol Volume

1.9K
The principle of conservation of mass is a fundamental law in fluid mechanics and is applied using the continuity equation. We apply the concept to a finite control volume to derive the continuity equation.
A system is defined as a collection of unchanging contents, and the conservation of mass states that a system's mass is constant.
1.9K
Steady, Laminar Flow Between Parallel Plates01:17

Steady, Laminar Flow Between Parallel Plates

1.0K
Understanding steady, laminar flow between parallel plates is essential for analyzing and designing flow in narrow rectangular channels, commonly found in various water conveyance and drainage systems. The Navier-Stokes equations govern fluid motion and are generally challenging to solve due to their nonlinearity. However, simplifications are possible in certain cases, like the steady laminar flow between parallel plates. For this scenario, we assume steady, incompressible, laminar flow.
1.0K
Control Volume and System Representations01:16

Control Volume and System Representations

1.7K
Two key frameworks are employed to analyze mass, energy, and momentum transfer: the control volume approach and the system approach. These frameworks offer different perspectives, depending on whether the focus is on a specific region in space (control volume approach) or a defined mass of fluid (system approach).
The control volume approach considers a stationary region in space through which fluid flows. This region is bounded by a control surface.  For instance, in the case of water...
1.7K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Modular instrument actuation unit for robotic-assisted systems in laparoscopic surgery.

International journal of computer assisted radiology and surgery·2026
Same author

User-centered design of graphical user interfaces for telemedical robotic systems: development and usability study.

International journal of computer assisted radiology and surgery·2026
Same author

Technology-assisted visceral surgery: a model-based approach for quantifying translation and accessibility across populations and geographies.

International journal of computer assisted radiology and surgery·2026
Same author

Deep learning for early detection of Zenker's diverticulum based on swallowing sound analysis.

International journal of computer assisted radiology and surgery·2026
Same author

Surgeon posture evaluation during simulated laparoscopic and robotic-assisted cholecystectomy.

International journal of computer assisted radiology and surgery·2026
Same author

Unwritten rules of healthcare assistance for robotic systems: multi-method workflow analysis of postoperative wound care treatments for the development of robotic assistive systems.

International journal of computer assisted radiology and surgery·2026
Same journal

Localization-driven exchange contrast in diffusion exchange spectroscopy.

Journal of magnetic resonance (San Diego, Calif. : 1997)·2026
Same journal

4.5 Tesla superconducting miniature magnet in liquid nitrogen.

Journal of magnetic resonance (San Diego, Calif. : 1997)·2026
Same journal

Folding and unfolding dynamics of a DNA aptamer studied by heteronuclear <sup>1</sup>H-<sup>13</sup>C correlation zz-exchange spectroscopy.

Journal of magnetic resonance (San Diego, Calif. : 1997)·2026
Same journal

Multi-spin control from one-spin pulses.

Journal of magnetic resonance (San Diego, Calif. : 1997)·2026
Same journal

Altering MRI rotating frame relaxations by changing the truncation level of Hyperbolic Secant pulse.

Journal of magnetic resonance (San Diego, Calif. : 1997)·2026
Same journal

Effects of proton exchange on the lifetimes of long-lived states in aliphatic chains.

Journal of magnetic resonance (San Diego, Calif. : 1997)·2026
See all related articles

Related Experiment Video

Updated: Apr 10, 2026

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
12:26

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics

Published on: August 27, 2013

18.2K

Fluid flow dynamics in MAS systems.

Dirk Wilhelm1, Armin Purea2, Frank Engelke2

  • 1Zurich University of Applied Sciences, Institute of Applied Mathematics and Physics, Techikumstrasse 9, 8400 Winterthur, Switzerland.

Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|June 16, 2015
PubMed
Summary
This summary is machine-generated.

High-performance magic angle spinning (MAS) probe turbines achieve high speeds but have low efficiency. Diagonal turbines may be better for high-speed MAS applications, and radial bearings show lower friction than predicted.

Keywords:
Computational fluid dynamicsMAS bearingMAS flow systemMAS turbineMagic angle spinning

More Related Videos

Cryogenic Liquid Jets for High Repetition Rate Discovery Science
08:34

Cryogenic Liquid Jets for High Repetition Rate Discovery Science

Published on: May 9, 2020

3.6K
The Diffusion of Passive Tracers in Laminar Shear Flow
08:01

The Diffusion of Passive Tracers in Laminar Shear Flow

Published on: May 1, 2018

9.2K

Related Experiment Videos

Last Updated: Apr 10, 2026

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
12:26

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics

Published on: August 27, 2013

18.2K
Cryogenic Liquid Jets for High Repetition Rate Discovery Science
08:34

Cryogenic Liquid Jets for High Repetition Rate Discovery Science

Published on: May 9, 2020

3.6K
The Diffusion of Passive Tracers in Laminar Shear Flow
08:01

The Diffusion of Passive Tracers in Laminar Shear Flow

Published on: May 1, 2018

9.2K

Area of Science:

  • Nuclear Magnetic Resonance Spectroscopy
  • Fluid Dynamics
  • Mechanical Engineering

Background:

  • High-performance magic angle spinning (MAS) probes are crucial for advanced NMR spectroscopy.
  • Optimizing turbine systems and radial bearings is essential for probe performance, particularly at high spinning rates.

Purpose of the Study:

  • To analyze the fluid flow properties of turbine systems and radial bearings in a 1.3mm-rotor diameter MAS probe.
  • To evaluate the efficiency and operational parameters of MAS turbines compared to classical turbomachinery.
  • To investigate frictional losses and temperature distribution within the radial bearings of MAS probes.

Main Methods:

  • Computational fluid dynamics (CFD) simulations were performed for the turbine and radial bearing systems.
  • Fluid measurements of the turbine and radial bearings were conducted.
  • MAS systems were analyzed using dimensionless values and compared with classical turbomachinery.

Main Results:

  • The 1.3mm-MAS rotor system exhibited low efficiency (approx. 25%), prioritizing speed and stability over energy efficiency.
  • Dimensionless analysis indicated that MAS turbine parameters are favorable and comparable to classical turbomachinery.
  • CFD simulations of radial bearings suggested lower frictional losses than theoretical models, but revealed significant rotor temperature gradients.

Conclusions:

  • MAS turbines are optimized for speed and stability, with efficiency being a secondary concern.
  • Radial turbines are suitable for low-speed MAS probes, while diagonal turbines are recommended for high-speed applications.
  • Further investigation into radial bearing models is needed to accurately predict frictional losses and manage rotor temperature.