1 / 10

Clothing and Insulation

Clothing and Insulation. Question:. If you stand in front of an open refrigerator, too far away for any cold air to reach you, would you feel colder than you would facing a wall in your home?. Retaining Heat. Heat flows from hot to cold Three major heat transfer mechanisms: Conduction

grace
Télécharger la présentation

Clothing and Insulation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Clothing and Insulation

  2. Question: If you stand in front of an open refrigerator, too far away for any cold air to reach you, would you feel colder than you would facing a wall in your home?

  3. Retaining Heat • Heat flows from hot to cold • Three major heat transfer mechanisms: • Conduction • Convection • Radiation • To minimize heat flow, impede all three

  4. Conduction • Conductive heat flow depends on • Temperature difference • Thermal conductivity • Proximity (inverse length) • To minimize conductive heat flow, minimize all three items

  5. Convection • Convective heat flow depends on • Temperature difference • Mobility of fluid • Heat capacity of fluid • Convection cell formation • To minimize convective heat flow, minimize all four items

  6. Radiation • Radiative heat flow depends on • Temperature difference • Absolute temperatures of surfaces • Emissivity of surfaces • To minimize radiative heat flow, minimize all three items

  7. Question: If you stand in front of an open refrigerator, too far away for any cold air to reach you, would you feel colder than you would facing a wall in your home?

  8. Human Adaptations • Thermally insulating skin • Hair • Counter-current exchange • Evaporative cooling

  9. Sound Insulation • To minimize sound transmission • Block the passage of sound waves • Cause sound waves to reflect

  10. Electric Insulation • To minimize current flow • Immobilize electric charges • Many other issues are also involved

More Related