Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

Two-Phase Flows: Final Review

Description

This lecture covers the final review of the Two-Phase Flows and Heat Transfer course, focusing on topics such as pool boiling, capillarity, wetting, evaporation, condensation, and flow boiling. The assessment includes homework assignments, group presentations, and a final exam. Various equations and models related to surface tension, contact angles, and bubble dynamics are discussed.

This video is available exclusively on Mediaspace for a restricted audience. Please log in to MediaSpace to access it if you have the necessary permissions.

Watch on Mediaspace

Official source

Related concepts (32)

Surface tension

Surface tension is the tendency of liquid surfaces at rest to shrink into the minimum surface area possible. Surface tension is what allows objects with a higher density than water such as razor blades and insects (e.g. water striders) to float on a water surface without becoming even partly submerged. At liquid–air interfaces, surface tension results from the greater attraction of liquid molecules to each other (due to cohesion) than to the molecules in the air (due to adhesion). There are two primary mechanisms in play.

Wetting

Wetting is the ability of a liquid to maintain contact with a solid surface, resulting from intermolecular interactions when the two are brought together. This happens in presence of a gaseous phase or another liquid phase not miscible with the first one. The degree of wetting (wettability) is determined by a force balance between adhesive and cohesive forces. Wetting is important in the bonding or adherence of two materials. Wetting and the surface forces that control wetting are also responsible for other related effects, including capillary effects.

Heat transfer

Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and transfer of energy by phase changes. Engineers also consider the transfer of mass of differing chemical species (mass transfer in the form of advection), either cold or hot, to achieve heat transfer.

Surface energy

In surface science, surface free energy (also interfacial free energy or surface energy) quantifies the disruption of intermolecular bonds that occurs when a surface is created. In solid-state physics, surfaces must be intrinsically less energetically favorable than the bulk of the material (the atoms on the surface have more energy compared with the atoms in the bulk), otherwise there would be a driving force for surfaces to be created, removing the bulk of the material (see sublimation).

Formative assessment

Formative assessment, formative evaluation, formative feedback, or assessment for learning, including diagnostic testing, is a range of formal and informal assessment procedures conducted by teachers during the learning process in order to modify teaching and learning activities to improve student attainment. The goal of a formative assessment is to monitor student learning to provide ongoing feedback that can help students identify their strengths and weaknesses and target areas that need work.

Related lectures (40)

Heat Transfer Processes

Covers the fundamentals of heat transfer processes, including convection, conduction, and radiation.

Flash Drum: Principles and Mass Balance in Separation Processes

Covers the principles of flash drums and the mass and energy balances involved in separation processes.

Evaporation Physics: Part I Log in to Mediaspace to watch this video

Explores evaporation physics, covering contact angles, wetting states, diffusion, Fick's Law, and heat-mass transfer analogy.

Evaporation vs Boiling: Phase Change Efficiency Log in to Mediaspace to watch this video

Explores the efficiency of phase change processes, focusing on evaporation and boiling, differentiating between the two and discussing the various regimes of pool boiling.

Capillarity and Wetting: Fundamentals and Applications Log in to Mediaspace to watch this video