A goniometric mask to measure contact angles from digital images of liquid drops

Biolè, D.; Bertola, Volfango

doi:10.1016/j.colsurfa.2014.10.060

Cited by 25 publications

(13 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This fitting range is consistent with previous research asserting that larger domains might not trace the drop profile accurately (Chini and Amirfazli 2011;Andersen and Taboryski 2017). This upper limit has also been discussed by Biolè and Bertola (2015), where their domain is determined by the need of their mask to follow the droplet curvature, which requires a small mask, and "accuracy in their area measurement, which requires a bigger mask". Technically speaking, our upper domain Fig.…”

Section: The Polynomial Fittingsupporting

confidence: 88%

“…In these cases, the goniometric mask method is often used. In this approach, a goniometer is digitally located at the contact line to automatically measure the contact angle formed at its proximity by the droplet (Biolè and Bertola 2015;Lee et al 2016a, b). Another suitable method for measuring the contact angle is through the fitting of a polynomial function to the droplet profile.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

On the analysis of the contact angle for impacting droplets using a polynomial fitting approach

Quetzeri-Santiago

Castrejón‐Pita

2020

Exp Fluids

View full text Add to dashboard Cite

Practical considerations on the measurement of the dynamic contact angle and the spreading diameter of impacting droplets are discussed in this paper. The contact angle of a liquid is commonly obtained either by a polynomial or a linear fitting to the droplet profile around the triple-phase point. Previous works have focused on quasi-static or sessile droplets, or in cases where inertia does not play a major role on the contact angle dynamics. Here, we study the effect of droplet shape, the order of the fitting polynomial and the fitting domain, on the measurement of the contact angle on various stages following droplet impact where the contact line is moving. Our results, presented in terms of the optical resolution and the droplet size, show that a quadratic fitting provides the most consistent results for a range of various droplet shapes. As expected, our results show that contact angle values are less sensitive to the fitting conditions for the cases where the droplet can be approximated to a spherical cap. Our experimental conditions include impact events with liquid droplets of different sizes and viscosities on various substrates. In addition, validating past works, our results show that the maximum spreading diameter can be parameterised by the Weber number and the rapidly advancing contact angle.

show abstract

Section: The Polynomial Fittingsupporting

confidence: 88%

Section: Introductionmentioning

confidence: 99%

On the analysis of the contact angle for impacting droplets using a polynomial fitting approach

Quetzeri-Santiago

Castrejón‐Pita

2020

Exp Fluids

View full text Add to dashboard Cite

show abstract

“…Recently, advanced techniques based on the local edge contour and on the image intensity gradient analysis were proposed [37,38]; unlike edge fitting approaches, these techniques are less sensitive to the image resolution. A simpler method, and the one used in the present work, is to approximate the local tangent with a line interpolating the three-phase-point and the nearest point of intersection between the drop contour and a horizontal line parallel to the baseline (i.e., a secant), as shown schematically in Fig.…”

Section: Contact Angle Measurementmentioning

confidence: 99%

Dynamic contact angle of dilute polymer solution drops impacting on a hydrophobic surface

Bertola

Wang

2015

Colloids and Surfaces A: Physicochemical and Engineering Aspect

Self Cite

View full text Add to dashboard Cite

“…The dynamic contact angle is obtained from the image by applying a goniometric mask (Biolè & Bertola 2015) on the region of 100 µm vertically above the surface line. As an example, figure 1 shows the typical time evolution of the spreading ratio β(t) = D(t)/D 0 , the dynamic contact angle θ D (t), as well as the maximum spreading ratio β max and the dynamic contact angle at maximum spreading θ D (t max ) for three liquids on a steel surface with V i ∼ 1.0 m s −1 .…”

Section: Drop Impact Experimentsmentioning

confidence: 99%

Universal rescaling of drop impact on smooth and rough surfaces

et al. 2015

View full text Add to dashboard Cite

The maximum spreading of drops impacting on smooth and rough surfaces is measured from low to high impact velocity for liquids with different surface tensions and viscosities. We demonstrate that dynamic wetting plays an important role in the spreading at low velocity, characterized by the dynamic contact angle at maximum spreading. In the energy balance, we account for the dynamic wettability by introducing the capillary energy at zero impact velocity, which relates to the spreading ratio at zero impact velocity. Correcting the measured spreading ratio by the spreading ratio at zero velocity, we find a correct scaling behaviour for low and high impact velocity and, by interpolation between the two, we find a universal scaling curve. The influence of the liquid as well as the nature and roughness of the surface are taken into account properly by rescaling with the spreading ratio at zero velocity, which, as demonstrated, is equivalent to accounting for the dynamic contact angle.

show abstract

A goniometric mask to measure contact angles from digital images of liquid drops

Cited by 25 publications

References 29 publications

On the analysis of the contact angle for impacting droplets using a polynomial fitting approach

On the analysis of the contact angle for impacting droplets using a polynomial fitting approach

Dynamic contact angle of dilute polymer solution drops impacting on a hydrophobic surface

Universal rescaling of drop impact on smooth and rough surfaces

Contact Info

Product

Resources

About