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Author(s) |
Gulawani, S. S.; Dahikar, S. K.; Mathpati, C. S.; Joshi, J. B.; Shah, M. S.; RamaPrasad, C. S.; Shukla, D. S.
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In direct contact condensation (DCC) phenomenon, whenever
steam (vapor) is injected with very high velocity in sub-cooled
water, the momentum and the energy of the steam is transfer red to the
surrounding liquid, leading to generation off low pattern,
turbulent in nature. The turbulent flow pattern enhances the heat transfer coefficient at the interface of steam jet and
water (vapor–liquid interface) as well as at the immersed surfaces (solid–liquid
interface). The flow and the temperature pattern in DCC system have been measured using hot film
anemometer (HFA). The values of heat transfer coefficient at the vapor–liquid and solid–liquid interface were estimated using the CCA module of the
HFA. The nozzle diameter (d0) was varied in the range of 1–2
mm and the nozzle up stream pressure in the range of 0.3– 0.35
MPa (corresponding velocities in the nozzle were 286–304m/s).
The time series of velocity and temperature at the interface were analyzed to get the rates of surface
renewal. A comparison has been presented between the predicted and the experimental values of heat transfer coefficient
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