Numerical investigation of the impacting and freezing process of a single supercooled water droplet

Yongkui Wang; Lei Ju; Duanfeng Han; Qing Wang

doi:10.1063/5.0048206

IMPROVED LUMPED-DIFFERENTIAL ANALYSIS OF THE FREEZING PROCESS IN A SUPERCOOLED WATER DROPLET

10.26678/abcm.encit2020.cit20-0502 ◽

2020 ◽

Author(s):

Emerson Barbosa dos Anjos ◽

Carolina Palma Naveira Cotta ◽

Renato Machado Cotta ◽

Igor Soares Carvalho ◽

Manish Tiwari

Keyword(s):

Water Droplet ◽

Supercooled Water ◽

Freezing Process ◽

Differential Analysis

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An improved lumped model for freezing of a freely suspended supercooled water droplet in air stream

Journal of Engineering Mathematics ◽

10.1007/s10665-021-10161-z ◽

2021 ◽

Vol 130 (1) ◽

Author(s):

Emerson B. dos Anjos ◽

Carolina P. Naveira-Cotta ◽

Manish K. Tiwari ◽

Renato M. Cotta ◽

Igor S. Carvalho

Keyword(s):

Water Droplet ◽

Supercooled Water ◽

Freezing Process ◽

Partial Differential ◽

Interface Position ◽

Spherical Droplet ◽

Differential Model ◽

Differential Formulation ◽

Air Stream ◽

Freely Suspended

AbstractThis work deals with the mathematical modeling of the transient freezing process of a supercooled water droplet in a cold air stream. The aim is to develop a simple yet accurate lumped-differential model for the energy balance for a freely suspended water droplet undergoing solidification, that allows for cost effective computations of the temperatures and freezing front evolution along the whole process. The complete freezing process was described by four distinct stages, namely, supercooling, recalescence, solidification, and cooling. At each stage, the Coupled Integral Equations Approach (CIEA) is employed, which reduces the partial differential equation for the temperature distribution within the spherical droplet into coupled ordinary differential equations for dimensionless boundary temperatures and the moving interface position. The resulting lumped-differential model is expected to offer improved accuracy with respect to the classical lumped system analysis, since boundary conditions are accounted for in the averaging process through Hermite approximations for integrals. The results of the CIEA were verified using a recently advanced accurate hybrid numerical-analytical solution through the Generalized Integral Transform Technique (GITT), for the full partial differential formulation, and comparisons with numerical and experimental results from the literature. After verification and validation of the proposed model, a parametric analysis is implemented, for different conditions of airflow velocity and droplet radius, which lead to variations in the Biot numbers that allow to inspect for their influence on the accuracy of the improved lumped-differential formulation.

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Freezing of water droplets colliding with kaolinite particles

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-4295-2009 ◽

2009 ◽

Vol 9 (13) ◽

pp. 4295-4300 ◽

Cited By ~ 28

Author(s):

E. A. Svensson ◽

C. Delval ◽

P. von Hessberg ◽

M. S. Johnson ◽

J. B. C. Pettersson

Keyword(s):

Water Vapor ◽

Relative Humidity ◽

Water Droplet ◽

Supercooled Water ◽

Dust Particles ◽

Freezing Process ◽

Water Droplets ◽

Electrodynamic Balance ◽

Dry Conditions

Abstract. Contact freezing of single supercooled water droplets colliding with kaolinite dust particles has been investigated. The experiments were performed with droplets levitated in an electrodynamic balance at temperatures from 240 to 268 K. Under relatively dry conditions (when no water vapor was added) freezing was observed to occur below 249 K, while a freezing threshold of 267 K was observed when water vapor was added to the air in the chamber. The effect of relative humidity is attributed to an influence on the contact freezing process for the kaolinite-water droplet system, and it is not related to the lifetime of the droplets in the electrodynamic balance. Freezing probabilities per collision were derived assuming that collisions at the lowest temperature employed had a probability of unity. Mechanisms for contact freezing are briefly discussed.

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Cascade Freezing of Supercooled Water Droplet Collectives

ACS Nano ◽

10.1021/acsnano.8b05921 ◽

2018 ◽

Vol 12 (11) ◽

pp. 11274-11281 ◽

Cited By ~ 8

Author(s):

Gustav Graeber ◽

Valentin Dolder ◽

Thomas M. Schutzius ◽

Dimos Poulikakos

Keyword(s):

Water Droplet ◽

Supercooled Water

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Effect of nucleation and icing evolution on run-back freezing of supercooled water droplet

Aerospace Systems ◽

10.1007/s42401-019-00032-y ◽

2019 ◽

Vol 2 (2) ◽

pp. 147-153

Author(s):

Mingming Sun ◽

Weiliang Kong ◽

Fuxin Wang ◽

Hong Liu

Keyword(s):

Water Droplet ◽

Supercooled Water

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Numerical Investigation of Stator Blades Bow Effect on the Rotor Blade Erosion of a Wet Steam Turbine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.670-671.769 ◽

2014 ◽

Vol 670-671 ◽

pp. 769-773

Author(s):

Hong Yao ◽

Wan Long Han ◽

Shi Ming Pan ◽

Zhong Qi Wang

Keyword(s):

Steam Turbine ◽

Numerical Investigation ◽

Water Droplet ◽

Mechanical Design ◽

Design Method ◽

Three Dimensional ◽

Rotor Blades ◽

Wet Steam ◽

Water Droplet Erosion ◽

Long Time

The water droplet erosion protection of the rotor blades has been an important issue for a long time, regardless of the design. The aim of this paper is to present a aerodynamic design method for decrease risk of water droplet erosion in wet steam turbine, as well as to present the comparison between then five diffrent bow stator blades. This paper also presents numerical investigation of three dimensional wet steam flows in a stage. This stage has long transonic blades designed using recent aerodynamic and mechanical design methods. The results show that, the one of the five diffrent bow stator blades decrease rist of water droplet erosion of rotaional blades, and the change of the efficiency is small.

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