Homogeneous nucleation boiling during jet impingement quench of hot surfaces above thermodynamic limiting temperature

Hasan, Mohammad Nasim; Monde, Masanori; Mitsutake, Yuichi

doi:10.1016/j.ijheatmasstransfer.2011.02.055

Cited by 19 publications

(12 citation statements)

References 10 publications

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“…We could not observe the bubble nucleation process on the other area such as Fig.6 from pictures taken at 45 s interval. The fact of the measured vapor film generation delay time within 45 s implies the spontaneous nucleation process as reported by Okuyama, et al [18] and Hassan, et al [19]. The nucleation area was gradually weakening due to evaporation of the residual liquid layer and finally disappeared.…”

Section: Visual Observationsupporting

confidence: 65%

Measurement and Observation of Elementary Transition Boiling Process after Sudden Contact of Liquid with Hot Surface

Mitsutake

Illias

Tsubaki

et al. 2015

Procedia Engineering

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A Fast response surface temperature measurement technique has been developed to investigate transient transition boiling phenomena after ethanol droplet impact on a nickel hot surface. Our motivation is to make clear the mechanism of boiling transition between nucleate and film boiling which is closely related the recovery of wetting on the hot surface being higher than the Leidenfrost temperature. In this study transient boiling phenomena during sudden contact of an ethanol sessile droplet on a hot solid surface has been investigated to understand what governs whether the solid surface keeps wet or not. The droplet impact boiling system is very simple and easier to observe but it includes the elementary transition boiling process. Since the transient transition took place within a couple ten milliseconds, observation with high speed video system and fast response surface temperature measurement technique are essential for better understanding of the transition boiling phenomena. The experiments were conducted for single and multiple droplet impacts. The multiple droplet impacts simulates liquid and solid contact situations on a hot surface during spray or laminar jet quench. The nickel disk of 50 mm in diameter and 5 mm in thickness was used as the hot surface. The hot surface was inclined from 0 deg (horizontal) to 40 deg. The fast-response film thermocouple with a typical minimum response time of 80 microseconds was developed and fabricated on the nickel disk at the depth of 3 micrometers from the surface. The temperature histories just beneath the surface were recorded at the sampling frequency of 200 kHz. The boiling phenomena beneath a sessile droplet impacted on the hot surface were observed by using a microscope equipped with the high speed video camera at the maximum frame rate of 22.5 kfps. The surface temperature and surface heat flux were estimated with 1D inverse heat conduction analysis. Histories of local surface temperature and local heat flux were compared with the boiling video image. The experiments were done for different initial wall temperatures up to 250 o C, different liquid subcoolings from 33 to 53 K. The multiple impact frequency was changed from 280 to 840 Hz. 6Yuichi Mitsutake et al. / Procedia Engineering 105 ( 2015 ) 5 -21 In case of the single droplet impact tests, the observation results showed that wetting situation was maintained for very short time even though the surface temperature was beyond the liquid superheat limit temperature. We defined the vapor film generation time as the characteristic boiling transition time scale from wetted nucleation boiling regime to dry film boiling regime. The film generation time were measured for the extensive initial surface temperature range, different subcoolings and different impact velocities. As the initial surface temperature increased, the film generation time decreased to order of microsecond and film boiling situation seemed to be established via spontaneous nucleation (vapor explosion) process. In case of the multiple droplets ...

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Section: Visual Observationsupporting

confidence: 65%

Measurement and Observation of Elementary Transition Boiling Process after Sudden Contact of Liquid with Hot Surface

Mitsutake

Illias

Tsubaki

et al. 2015

Procedia Engineering

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“…A mechanistic model proposed by the authors [6,10] has been used in which a particular stage of liquid heating is defined as the homogeneous nucleation boiling explosion during which bubble generation and growth due to homogeneous nucleation inside a characteristic liquid cluster, x e , causes the average cluster temperature, T avg , to decrease namely, dT avg /dt 6 0. A detail description of the model is provided in Appendix A.…”

Section: Present Approachmentioning

confidence: 99%

“…In addition, the authors [10] applied their proposed model to another case in which water at a temperature of 20°C contacts with hot steel surface at atmospheric pressure and showed that the boiling explosion does not take place at a surface temperature lower than 336°C. In this model study, the time when the boiling explosion occurs after the liquid contact with the solid surface is found to depend strongly on the solid temperature.…”

Section: Introductionmentioning

confidence: 99%

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Lower limit of homogeneous nucleation boiling explosion for water

Hasan

Monde

Mitsutake

2011

International Journal of Heat and Mass Transfer

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“…[1][2][3][4][5][6][7][8][9][10][11][12] It is well-known that the heat flux from the hot solid to the jets depends on the temperature of the solid and the existence of boiling regimes. The heat flux is also dependent on the coolant conditions, including the jet diameter and the velocity and temperature of the coolant.…”

Section: Introductionmentioning

confidence: 99%

Heat Transfer Characteristics of a Circular Water Jet Impinging on a Moving Hot Solid

et al. 2014

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The heat transfer characteristics of a circular water jet impinging on a moving hot solid were investigated experimentally. In the experiments, distilled water at room temperature was used as the test coolant. The circular jet issued from a 5-mm-diameter pipe nozzle, fell vertically downward, and impinged on a horizontal moving sheet made of 0.3-mm-thick stainless steel. The initial temperature of the sheet, the jet velocity, and the moving sheet velocity were varied systematically. The initial temperature of the moving sheet was set to 100, 150, 200, or 250°C. The mean velocity at the nozzle exit was 0.4, 0.8, or 1.2 m/s, and the moving velocity was 0.5, 1.0, or 1.5 m/s. Observations made using flash photography and thermography showed that the location of the front edge of the liquid film formed upstream of the jet impact point depends on all of these factors. The local heat flux is very small in the dry area, increases steeply near the front edge of the liquid film, and reaches a peak. If the distance between the front edge of the liquid and the jet impact point is relatively large, a second peak appears near the jet impact point. An experimental correlation was developed for predicting peak heat fluxes near the front edge of the liquid, although it has no theoretical background. The correlation agrees moderately well with the experiments.

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Homogeneous nucleation boiling during jet impingement quench of hot surfaces above thermodynamic limiting temperature

Cited by 19 publications

References 10 publications

Measurement and Observation of Elementary Transition Boiling Process after Sudden Contact of Liquid with Hot Surface

Measurement and Observation of Elementary Transition Boiling Process after Sudden Contact of Liquid with Hot Surface

Lower limit of homogeneous nucleation boiling explosion for water

Heat Transfer Characteristics of a Circular Water Jet Impinging on a Moving Hot Solid

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