Heating compressed air to provide lift

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Discussion Overview

The discussion revolves around the concept of heating compressed air and its potential to provide lift. Participants explore the relationship between temperature, density, and lift in both compressed and uncompressed air, focusing on theoretical implications and practical understanding.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions whether heating compressed air can provide lift, comparing it to uncompressed air heated to the same temperature.
  • Another participant asserts that compressed air is heavier than uncompressed air, suggesting it will not provide lift.
  • A later reply clarifies that heating compressed air could potentially provide lift if the air expands and its density becomes less than that of the surrounding atmosphere, but notes that this would no longer be considered compressed air.
  • One participant acknowledges a misunderstanding of the concept of compressed air following the responses.

Areas of Agreement / Disagreement

Participants express differing views on whether heating compressed air can provide lift, indicating a lack of consensus on the topic.

Contextual Notes

The discussion includes assumptions about the definitions of compressed and uncompressed air, as well as the conditions under which lift can be achieved. There are unresolved aspects regarding the specific calculations of lift and the effects of heating on air density.

dankelly08
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Just a question about heating compressed air..

I know generally how hot air works.. You heat it and particles expand and creates lift.

So my question is, Does heating compressed air provide any lift? if so how much in relation to normal air?
eg
if I had 100m^3 of air heated to 120C,
would it provide the same lift as the (same amount) but now compressed air heated to 120C

Does this make sense? or have I missed the point...
 
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No, it won't provide any lift at all. Compressed air is heavier than uncompressed air.
 
dankelly08 said:
Just a question about heating compressed air..

I know generally how hot air works.. You heat it and particles expand and creates lift.

So my question is, Does heating compressed air provide any lift? if so how much in relation to normal air?
eg
if I had 100m^3 of air heated to 120C,
would it provide the same lift as the (same amount) but now compressed air heated to 120C

Does this make sense? or have I missed the point...
In order to rise, the density of the air has to be less than the density of the surrounding atmosphere. Heating compressed air could provide lift if it was heated and allowed to expand so that its density was less than the surrounding atmosphere. But then it would not be compressed air. as Vanadium has pointed out.

AM
 
Ah I see, I misunderstood the concept of compressed air, thanks for your replies.
 

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