The best known version  of the experiment was started in by Professor Thomas Parnell of the University of Queensland in BrisbaneAustralia, to demonstrate to students that some substances which appear solid are actually highly viscous fluids. Parnell poured a heated sample of pitch into a sealed funnel and allowed it to settle for three years. Inthe seal at the neck of the funnel was cut, allowing the pitch to start flowing. A glass dome covers the funnel and it is placed on display outside a lecture theatre.
High-resolution quality video images from the very simple to conduct experiments provide direct confirmation of the usefulness of current analytical design tools as well as provide guidance to the development of new ones. Results from these experiments are used to develop more accurate fluid models to aide in the design of low gravity fluid systems and enhance the fluid transfer systems of future space vehicles.
The ullage empty part of the container migration rates of five different flows dry, wet, open loop, closed loop, and bubbly flows in the units were observed and compared to theoretical predictions.
Migration rates were found to be in surprising agreement with predictions for the dry tests, but were under-predicted for previously wetted surfaces which are common in such systems. This analysis is ongoing and will be Fluid flow experiment 11 in part with further experimental results to be collected during CFE-2 experiments currently onboard ISS.
In many cases bubbles are separated passively due to the specific geometry of the containers providing a no-moving-parts solution to this low-gravity challenge. Vane Gap VG Results The Capillary Flow Experiment-Vane Gap CFE-VG studies capillary flow when there is a gap between interior corners, such as in the gap formed by an interior vane and tank wall of a large propellant storage tank or the near intersection of vanes in a tank with a complex vane network.
The CFE-VG experiment highlights the sensitivity of a capillary fluid surface to container shape and how small changes to the shape may result in dramatic global shifts of the liquid within the container.
Understanding such behaviors is central to the passive management of liquids aboard spacecraft and in certain cases permits us the ability to move pump large quantities potentially tons of liquid by a simple choice of container shape.
In particular, the Vane-Gap experiments identify the critical geometric wetting conditions of a vane structure that does not quite meet the container wall—a construct arising in various fluid systems aboard spacecraft such as liquid fuel and cryogen storage tanks, thermal fluids management, and water processing equipment.
Critical vane gap wetting, as demonstrated by the flight experiments, is dependent on the vane angle and fluid wetting properties, similarly as for ideal sharp corners, but also by the additional geometric effects of the specific vane gap, vane thickness, container size and shape, and even time.
In the case of the perfectly wetting fluid of VG-1, six wetting and de-wetting configurations were produced: De-wetting of all these conditions is also studied. The most noteworthy condition was the bulk shift due to the considerable amount of liquid that was transferred.
However, the bulk shift phenomena was not predicted by analysis, which assumed perfect geometric symmetry of vane and cylinder. The occurrence of bulk shift indicates that small irregularities in geometry such as tiny unavoidable imperfections within the manufacturing tolerance of the experiment unit can influence fluid behavior in a significant way.
Post flight measurements of test cell asymmetries were made to quantify such values and new predictions were made of the slightly asymmetric vessel. The theory was extended to address critical wetting events attributable to finite asymmetries verses infinitesimal ones.
The agreement is informative as a method to assess tank symmetry for applications aboard spacecraft.
For the partial wetting fluid of VG-2, critical wetting occurred along both the small and large gaps, similar to VG However, unlike VG-1, the difference between the critical angles observed and predicted was substantial, and is likely due to asymmetry inherent in the experiment unit and contact angle hysteresis the difference between the receding uphill angle and advancing downhill contact angle made by the fluid on a tilted plane right before the fluid drop begins to roll.
Bulk shift of the fluid was not predicted and did not occur.
Contact Line CL Results CFE-CL investigates the properties of the contact line the boundary between the liquid, gas, and solid surface of the containerwhich controls the interface shape, stability, and dynamics of capillary systems in low gravity.
From the over events evaluated thus far, damping rate, frequency and qualitative waveform were found to be significantly influenced by contact line and contact angle conditions. The pinning condition produced higher frequencies and lower damping rates than the smooth condition.
Larger contact angles also produced the same trend in higher frequencies and lower damping rates. Fluid depth was found to have little effect on the fluid response to disturbances except in cases where shallow tests were performed intentionally Weislogel Observed results were also compared to model predictions.
Agreement between numerical predictions and observed results varied widely. The most accurately modeled instance was the perfectly wetting case of CL-2 for both the pinning and smooth conditions and for both axial and lateral disturbance events.
The least accurately modeled instances are the high contact angle push-type disturbance events with free-slip conditions, since contact line translation is not included in the constant contact angle slip model. In general, modeled and observed results were in best agreement for pinned conditions, as a result of the more predictable and confined contact line movement.
Phase Separation Capillary solutions have long existed for the control of fluids in spacecraft fluid systems such as liquid propellants, cryogens and thermal fluids for temperature regulation.
Such methods have only been confidently established if the wetting conditions are known and favorable. However, capillary solutions for water-based systems aboard spacecraft are often ignored due to poor and unpredictable wetting properties. Application of CFE findings to spacecraft fluid systems is direct Weislogel et al.Las Positas College Lab #12 Fluid Flow Nov07 1 Lab Fluid Flow I.
Introduction: In the first experiment we validate Torricelli’s law, which shows (ignoring viscosity) that the exit speed of a fluid depends only on the height of the column of water above it.
The second 11/7/ AM. Experiment PVC - Influence of plasticizer content and testing temperature. Aim: (a) To make "plastisol" compositions (suspension of fine spherical particle of PVC in a liquid like di-octyl phthalate, DOP), in which the PVC/DOP ratio is varied.
Credit: NASA Quest. From his experiments, Bernoulli concluded that when a fluid is moving faster, it has lower pressure. This is known as Bernoulli’s Principle, and it is used to explain many.
Oct 21, · Taylor-Couette flow is the name of a fluid flow and the related instability that occurs in the annulus between differentially rotating concentric cylinders, most often with the inner cylinder rotating and the outer cylinder fixed, when the rotation rate exceeds a critical value.
The stable base flow was used in the 19th century to test the fundamental Newtonian stress assumption in the Navier. Fulfillment by Amazon (FBA) is a service we offer sellers that lets them store their products in Amazon's fulfillment centers, and we directly pack, ship, and provide customer service for these products.
In this experiment, you will investigate fluid flow in a pipe network and will explore several methods (rotameter, orifice and venturi meters) for measurement of the fluid flow rate.
You will also explore effects of the skin (11) ECH L Unit Operations Lab I Fluid Flow where C D is the drag coefficient, A p.