Related Experiment Video
Updated: Aug 6, 2026

Analyzing Mixing Inhomogeneity in a Microfluidic Device by Microscale Schlieren Technique
Published on: June 12, 2015
Comment on "Dynamically maintained steady-state pressure gradients"
1Center for Science Education, Portland State University, P.O. Box 751, Portland, Oregon 97207, USA.
Abstract:
Sheehan [Phys. Rev. E 57, 6660 (1998)] recently discussed the possibility of establishing a dynamically maintained, steady-state pressure gradient in a gas filling a cavity. In this Comment it is pointed out that the pressure gradients in such a system, if attainable in the laboratory, could be used to violate the second law of thermodynamics.
Related Concept Videos
Pascal's Law
Fluid Pressure over Flat Plate of Variable Width
The pressure distribution on the plate can be calculated by determining the force that acts on a differential area strip of the plate. Thus, the magnitude of the force is equal to the...
Pressure Variation in a Fluid at Rest
When measuring pressure at two different levels within the fluid, the difference in pressure...
Bernoulli's Equation for Flow Normal to a Streamline
The pressure difference depends on the fluid's velocity and radius of curvature. The pressure variation is minimal in flows with nearly straight streamlines. However, the...
Static, Stagnation, Dynamic and Total Pressure
Steady, Laminar Flow Between Parallel Plates

