Bubble time-of-flight: A simple method for measuring microliter per minute flows without calibration

Lippmann, Julian M.; Pisano, Albert P.

doi:10.1016/j.sna.2011.11.018

Cited by 3 publications

(2 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Particularly, the flow rate was measured by determining the time a bubble travels a distance of 10 mm. This method, measuring the flow rate based on the speed of a bubble, also known as bubble time-of-flight, was employed by referring to various literatures 14 , 27 , 28 . The movement of a bubble was captured using a camera (TG-5, OLYMPUS), and the pump was driven using a high voltage power supply 29 .…”

Section: Resultsmentioning

confidence: 99%

Peristaltic micropump using polyvinyl chloride gels with micropatterned surface

Motohashi

Ogawa

Akai

et al. 2022

Sci Rep

View full text Add to dashboard Cite

This paper presents a pump using polyvinyl chloride (PVC) gel. PVC gels are compliant, have a simple structure, and exhibit large deformation at voltages in the range of 100–1000 V, which make them suitable for micropumps. In this study, a PVC gel sheet with a surface pattern that enhances active deformation in the thickness direction was employed for the fabrication of a pump. To this end, the PVC gel sheet was sandwiched between three sets of anode and cathode electrodes, after which voltages were sequentially applied to these electrodes to generate a peristaltic deformation of the gel sheet, thus pushing the liquid and creating a one-directional flow. Various pumps were fabricated using PVC gel sheets with different surface patterns, and the pumps were characterized. The pumps exhibited an outline dimension of 35 mm × 25 mm with a thickness of 4 mm, corresponding to a total volume of 3.5 × 103 mm3. The results revealed that the pump fabricated using a 174-μm-high pyramid-patterned gel sheet generated a flow rate of 224.1 µL/min at an applied voltage of 800 V and a driving frequency of 3 Hz. This observed value is comparable to or better than those of existing pumps based on smart materials.

show abstract

Section: Resultsmentioning

confidence: 99%

Peristaltic micropump using polyvinyl chloride gels with micropatterned surface

Motohashi

Ogawa

Akai

et al. 2022

Sci Rep

View full text Add to dashboard Cite

show abstract

“…Others have chosen to measure flow (low microliter per minute) by generating and sensing O 2 electrochemically. In another microfabricated setup, the liquid passed over a zone pulse-heated to boil and form an ∼10 mm long bubble, or GBMs were introduced with a syringe . An array of sensing electrodes (each ∼1 mm wide) was deployed on either side of the flow channel to sense the passage of the GBMs either (a) by the duration of the disturbance signal across a single adjacent pair of electrodes (in the present work, we call this time of sight, TOS) or (b) the TOF between any two electrode pairs.…”

Section: Thermal Flowmetersmentioning

confidence: 99%

Time-of-Sight Liquid Flow Measurements in the Low Nanoliters per Minute Scale

Qin

Dasgupta

2019

Anal. Chem.

View full text Add to dashboard Cite

We describe an affordable and robust measurement technique applicable to nanoscale liquid flow. The approach can provide good precision (<1% RSD) in the 1.5–15 nL/min flow range. The motion of a conductive/nonconductive immiscible segmental interface in a capillary is followed by an admittance detector. The conductive marker segment, e.g., a salt solution, is protected on both sides from the principal flow stream by immiscible guard segments, typically a fluorocarbon (FC) liquid, of significantly greater impedance. Fluorosilylation of the capillary ensures no other liquid film between the FC segments and the wall (perfect piston). A given interface/marker can typically be used only once in interface/front tracking systems. We overcome this by putting the sensor capillary in a valved configuration where the flow direction in the sensor is reversed before the guard/marker segments escape. Several strategies are possible to interpret flow rate from the sensor output, including the rate of the interface movement. During the measurement process, a change in this rate of movement can be detected in <1 s. Small temperature variations in the 25–35 °C range did not affect sensor behavior.

show abstract