Author: J. T. O'Bara
Publisher:
ISBN:
Category :
Languages : en
Pages : 27
Book Description
In the first phase of this work equivalent heat transfer coefficients at atmospheric pressure for the dropwise condensation of steam were determined experimentally. The coefficients rangef from 1,140 to 37,200 BTU/hr sq ft deg F for heat fluxes of 167,000 down to 29,900 BTU/hr sq ft deg F with surface temperature differences carying from 2 to 45F. Vapor velocities varied from 1.75 to 7.52 ft/sec. It was observed that the vapor velocity across the condensing surface has a significant effect on the equivalent transfer coefficient with the coefficient exhibiting a maximum with increasing vapor velocity. It is believed that this maximum reflects the transition between dropwise and mixed condensation resulting from the greater vapor-liquid interfacial shear stress developed at high vapor velocities. Visual observations showed that, as the pressure increases, a transition from dropwise to mixed condensation occurs between 25 and 50 psig. This transition is posited to be associated with the decreased surface tension of the condensed phase at the higher saturation temperatures. (Author).
Dropwise Condensation of Steam at Atmospheric and Above Atmospheric Pressures
Author: J. T. O'Bara
Publisher:
ISBN:
Category :
Languages : en
Pages : 27
Book Description
In the first phase of this work equivalent heat transfer coefficients at atmospheric pressure for the dropwise condensation of steam were determined experimentally. The coefficients rangef from 1,140 to 37,200 BTU/hr sq ft deg F for heat fluxes of 167,000 down to 29,900 BTU/hr sq ft deg F with surface temperature differences carying from 2 to 45F. Vapor velocities varied from 1.75 to 7.52 ft/sec. It was observed that the vapor velocity across the condensing surface has a significant effect on the equivalent transfer coefficient with the coefficient exhibiting a maximum with increasing vapor velocity. It is believed that this maximum reflects the transition between dropwise and mixed condensation resulting from the greater vapor-liquid interfacial shear stress developed at high vapor velocities. Visual observations showed that, as the pressure increases, a transition from dropwise to mixed condensation occurs between 25 and 50 psig. This transition is posited to be associated with the decreased surface tension of the condensed phase at the higher saturation temperatures. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 27
Book Description
In the first phase of this work equivalent heat transfer coefficients at atmospheric pressure for the dropwise condensation of steam were determined experimentally. The coefficients rangef from 1,140 to 37,200 BTU/hr sq ft deg F for heat fluxes of 167,000 down to 29,900 BTU/hr sq ft deg F with surface temperature differences carying from 2 to 45F. Vapor velocities varied from 1.75 to 7.52 ft/sec. It was observed that the vapor velocity across the condensing surface has a significant effect on the equivalent transfer coefficient with the coefficient exhibiting a maximum with increasing vapor velocity. It is believed that this maximum reflects the transition between dropwise and mixed condensation resulting from the greater vapor-liquid interfacial shear stress developed at high vapor velocities. Visual observations showed that, as the pressure increases, a transition from dropwise to mixed condensation occurs between 25 and 50 psig. This transition is posited to be associated with the decreased surface tension of the condensed phase at the higher saturation temperatures. (Author).
The Dropwise Condensation of Steam on a Gold-plated Tube at Atmospheric Pressure
Promotion of Dropwise Condensation of Steam on Fouled Brass Tubes by Injection of Promoter at Sub-atmospheric Pressure
Author: Bernard David John Osment
Publisher:
ISBN:
Category :
Languages : en
Pages : 26
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 26
Book Description
NBS Special Publication
Author:
Publisher:
ISBN:
Category : Weights and measures
Languages : en
Pages : 1164
Book Description
Publisher:
ISBN:
Category : Weights and measures
Languages : en
Pages : 1164
Book Description
Report
Author: United States. National Bureau of Standards
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 696
Book Description
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 696
Book Description
Convective Boiling and Condensation
Author: John G. Collier
Publisher: Clarendon Press
ISBN: 0191591262
Category :
Languages : en
Pages : 646
Book Description
* Third edition of a well-known and well established text both in industry and for teaching * Fully up-to-date and includes extra problems This book is an aid to heat exchanger design written primarily for design and development engineers in the chemical process, power generation, and refrigeration industries. It provides a comprehensive reference on two-phase flows, boiling, and condensation. The text covers all the latest advances like flows over tube bundles and two-phase heat transfer regarding refrigerants and petrochemicals. Another feature of this third edition is many new problems at chapter ends to enhance its use as a teaching text for graduate and post-graduate courses on two-phase flow and heat transfer. - ;This book is written for practising engineers as a comprehensive reference on two-phase flows, boiling, and condensation. It deals with methods for estimating two-phase flow pressure drops and heat transfer rates. It is a well-known reference book in its third edition and is also used as a text for advanced university courses. Both authors write from practical experience as both are professional engineers. -
Publisher: Clarendon Press
ISBN: 0191591262
Category :
Languages : en
Pages : 646
Book Description
* Third edition of a well-known and well established text both in industry and for teaching * Fully up-to-date and includes extra problems This book is an aid to heat exchanger design written primarily for design and development engineers in the chemical process, power generation, and refrigeration industries. It provides a comprehensive reference on two-phase flows, boiling, and condensation. The text covers all the latest advances like flows over tube bundles and two-phase heat transfer regarding refrigerants and petrochemicals. Another feature of this third edition is many new problems at chapter ends to enhance its use as a teaching text for graduate and post-graduate courses on two-phase flow and heat transfer. - ;This book is written for practising engineers as a comprehensive reference on two-phase flows, boiling, and condensation. It deals with methods for estimating two-phase flow pressure drops and heat transfer rates. It is a well-known reference book in its third edition and is also used as a text for advanced university courses. Both authors write from practical experience as both are professional engineers. -
The Effect of a Novel Coating Technique on Filmwise and Dropwise Condensation of Steam on Horizontal Tubes
Author: Helen P. Kilty
Publisher:
ISBN: 9781423583172
Category :
Languages : en
Pages : 255
Book Description
Steam condensation heat transfer on smooth horizontal tubes and on a Korodense horizontal tube was experimentally studied at atmospheric pressure and at vacuum. The overall heat transfer coefficient was measured and the outside heat transfer coefficient was determined from the modified Wilson Plot Technique. A hydrophobic coating of a self-assembling monolayer (SAM) with a composition of HS(CH2)15 CH3 promoted excellent dropwise condensation (DWC) on tubes. Coexisting strips with varying widths of filmwise condensation (FWC) and DWC, but at a constant area ratio of 50%, were also investigated.
Publisher:
ISBN: 9781423583172
Category :
Languages : en
Pages : 255
Book Description
Steam condensation heat transfer on smooth horizontal tubes and on a Korodense horizontal tube was experimentally studied at atmospheric pressure and at vacuum. The overall heat transfer coefficient was measured and the outside heat transfer coefficient was determined from the modified Wilson Plot Technique. A hydrophobic coating of a self-assembling monolayer (SAM) with a composition of HS(CH2)15 CH3 promoted excellent dropwise condensation (DWC) on tubes. Coexisting strips with varying widths of filmwise condensation (FWC) and DWC, but at a constant area ratio of 50%, were also investigated.
Scientific and Technical Aerospace Reports
Condensation of Steam and Air Mixtures at Atmospheric Pressure
Current Hydraulic Laboratory Research in the United States
Author:
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 334
Book Description
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 334
Book Description