Condensation heat transfer in a sessile droplet at varying Biot number and contact angle

Sanjay Adhikari, Mahdi Nabil, Alexander S. Rattner

Research output: Contribution to journalArticle

6 Scopus citations

Abstract

Dropwise condensation has been identified as a promising heat transfer mechanism because it can yield heat fluxes up to an order of magnitude higher than typically found in filmwise condensation. Models for dropwise condensation generally assume a statistical distribution of droplet sizes and integrate heat transfer over the droplet size spectrum, considering droplet curvature effects on saturation temperature, conduction thermal resistance, and interfacial resistance. Most earlier studies have assumed a constant heat transfer factor (f = O(1)) to account for the conduction contribution to total thermal resistance. However, f varies with droplet Biot number (Bi) and contact angle (θ). Formulations for f with broad ranges of applicability are not currently available. In this study, finite element simulations are performed to determine f and corresponding numerical uncertainties for 0.0001 ⩽ Bi ⩽ 1000 and 10° ⩽ θ ⩽ 170°. This spans the active droplet size range considered in most droplet condensation studies (e.g., for water condensing at Patm on a surface 10 K below the ambient temperature, active droplets have 0.0005 < Bi < 300). An explicit correlation is proposed for f and is validated with published results. The proposed correlation can facilitate modeling and analysis of dropwise condensation.

Original languageEnglish (US)
Pages (from-to)926-931
Number of pages6
JournalInternational Journal of Heat and Mass Transfer
Volume115
DOIs
StatePublished - Jan 1 2017

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanical Engineering
  • Fluid Flow and Transfer Processes

Fingerprint Dive into the research topics of 'Condensation heat transfer in a sessile droplet at varying Biot number and contact angle'. Together they form a unique fingerprint.

  • Cite this