Experimental study on pressure and temperature distributions for low mass flux steam jet in subcooled water

Abstract

A low mass flux steam jet in subcooled water was experimentally investigated. The transition of flow pattern from stable jet to condensation oscillation was observed at relatively high water temperature. The axial total pressures, the axial and radial temperature distributions were measured in the jet region. The results indicated that the pressure and temperature distributions were mainly influenced by the water temperature. The correlations corrected with water temperature were given to predict the dimensionless axial pressure peak distance and axial temperature distributions in the jet region, the results showed a good agreement between the predictions and experiments. Moreover, the self-similarity property of the radial temperature was obtained, which agreed well with Gauss distribution. In present work, all the dimensionless properties were mainly dependent on the water temperature but weakly on the nozzle size under a certain steam mass flux.

Development of A Mechanical Setup With Sensors to Determine Interfacial Phenomena Between Supersonic Steam Jet and Water

“…At elevated water's temperature in the column, the jet became ercely unstable because, at elevated values for the temperature, the interface moved with larger velocity than the surrounding water, this resulted into the formation of KH instability at the interface. Moreover, the temperature pro le in Figure 8, seems non-symmetric, the region within the centreline of the jet at a radial distance, r = 0, particularly when the temperature of the water in the column exceeds 45 o C. It can also be seen in Figure 8, that the width of the jet has been raised with a rise in pressure, which supports work performed elsewhere [18][15] [25] [19]. The temperature pro les obtained at all pressures show peak temperature values at r=0, these values decrease to the ambient when the temperature sensors were moved away from the centre of the jet, which is found consistent with work reported by Song, Cho, & Kang, 2012 [26]; X.-Z.…”

“…In uence of Water Temperature & Steam Inlet Pressure: Axial temperature measurements presented in Figure 5 were obtained with the steam's inlet pressure varying within 1.5 -3.0 bars, whereas, the temperature of the water in the tank ranged from 30 o C to 60 o C. The temperature pro le obtained at 30 o C shows that the temperature reduces along the axis, however, in the region close to the nozzle's exit, the pro le reveals independence from the temperature of the surrounding water [14], [15], [16], [17]. When the water temperature in the column increased, the nature of the temperature pro le along the axis developed highly uctuating.…”

“…Also, uctuations shifted to the right, as seen in Figure. 6, exhibiting a dislocation of the interface away from the nozzle's exit to the water region. These uctuations may be ascribed as condensation oscillation (CO) as reported by Arinobu, 1980 [23]; Aya & Nariai, 1991 [24]; Chun et al, 1996 [22]; Yan et al, 2010 [20] which occurred at low mass ux with rise in water temperature in the vessel, thus giving rise to the instability at the interface of the steam jet and water [25]. Formation of these uctuations along the axial axis of the jet at the temperature of the water in the vessel greater than 45 o C may contribute to increase the shear across the interface, which caused KH instabilities.…”

CFD Simulation on Pressure Profile for Direct Contact Condensation of Steam Jet in a Narrow Pipe

“…However, a detailed description could not be provided due to the complexity of the situation. Yan et al [19] measured the axial total pressures for low mass flux steam jet in subcooled water, and found it decreases initially and then increases with the axial distance, reaching a peak before returning to ambient pressure. A dimensionless correlation for predicting the peak distance of total pressure is obtained.…”