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Re: Convection is fiction

From Poutnik <poutnik4nntp@gmail.com>
Newsgroups sci.physics
Subject Re: Convection is fiction
Date 2016-08-22 17:45 +0200
Organization A noiseless patient Spider
Message-ID <npf6mu$9r6$1@dont-email.me> (permalink)
References <e5b8b178-c782-4768-ac07-0cf0b4f62c15@googlegroups.com> <upq9rb9itah8fb03u990e1ppt12tsbr004@4ax.com> <23764527.rf7BzDKH0Z@PointedEars.de>

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On 08/21/2016 05:57 PM, Thomas 'PointedEars' Lahn wrote:

> ....atmospheric pressure that
> is decreasing approximately exponentially with altitude within the higher
> troposphere:
>
>   p ≈ p₀ exp(−g M h∕(R T₀))
>
> where
>
>   p  – atmospheric pressure
>   p₀ – standard atmospheric pressure at sea level (101'326 Pa)
>   g  – Earth-surface gravitational acceleration (ca. 9.81 m∕s²)
>   M  – molar mass of dry air (ca. 0.03 kg∕mol)
>   h  – altitude
>   R  – universal gas constant (ca. 8.31 J mol⁻¹ K⁻¹)
>   T₀ – standard temperature at sea level (288.15 K = 15 °C)
>

This approximation serves well for low troposhere near sea level,
but does not count with the decreasing of temperature with altitude.

The air of top troposphere has temperature about 218 K = - 55 deg C,
that leads to about 1.32 higher density and pressure gradient,
compared to 288 K.

While the vertical temperature gradient called lapse rate  (*)
canvary a lot, it is well described by typical mean value
chosen for the standard atmosphere :

T=T0 - gamma.h  ,
T0= 298.15K, gamma ( lapse rate ) = - dT/dh = 0.0065K/m, p0 = 101325 Pa.

ro = p.M/(R.T), M is mean air molar mass [ ro = density ]

dp = - g.ro . dh = - g . p.M/(R.(T0 - gamma.h) . dh

dp/p = -g.M/R . dh/(T0 - gamma .h)

[ln(|p|)](p0..p) = -g.M/R . (-1/b) . [ln(|T0-gamma.h|)] (0..h)

ln(p/p0) = +g.M/R/gamma . ln((T0-gamma.h)/T0)

p = p0 . [1 - gamma.h/T0)]^(g.M/R/b)

(*) https://en.wikipedia.org/wiki/Lapse_rate

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Thread

Convection is fiction Claudius Denk <claudiusdenk@gmail.com> - 2016-08-13 09:44 -0700
  Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-13 15:14 -0700
  Re: Convection is fiction Michael J. Strickland <michael06582@comcast.net> - 2016-08-17 19:01 -0400
    Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-17 16:28 -0700
      Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-17 22:20 -0700
    Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-21 17:57 +0200
      Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-21 18:16 +0200
        Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-21 18:46 +0200
          Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-21 18:56 +0200
            Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-21 19:09 +0200
              Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-21 19:27 +0200
              Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 07:39 +0200
                Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-22 19:58 -0700
              Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 17:17 +0200
                Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-22 20:02 -0700
            Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-21 12:38 -0700
              Re: Convection is fiction Claudius Denk <claudiusdenk@gmail.com> - 2016-08-21 17:11 -0700
                Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-21 19:59 -0700
        Re: Re: Convection is fiction Michael J. Strickland <michael06582@comcast.net> - 2016-08-21 22:34 -0400
          Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 06:52 +0200
          Re: Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-22 19:02 +0200
            Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 19:17 +0200
              Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-22 20:05 -0700
              Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 01:16 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 05:53 +0200
                Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 18:47 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 21:04 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:09 +0200
                Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 19:03 +0200
                Re: Convection is fiction Sergio <invalid@invalid.com> - 2016-08-24 12:16 -0500
                Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-24 11:11 -0700
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 21:36 +0200
                Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-25 06:20 +0200
                Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-25 08:13 +0200
                Re: Convection is fiction Sergio <invalid@invalid.com> - 2016-08-25 09:40 -0500
      Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-21 12:14 -0700
      Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 17:45 +0200
        Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-22 18:56 +0200
          Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 19:14 +0200
            Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 20:54 +0200
              Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 01:56 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:02 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:14 +0200
                Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 19:07 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 21:15 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:31 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:54 +0200
            Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 01:10 +0200
              Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 05:53 +0200
              Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 07:32 +0200
                Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 19:15 +0200
                Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 21:11 +0200
                Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 21:26 +0200
                Re: Convection is fiction Sergio <invalid@invalid.com> - 2016-08-24 15:07 -0500
        Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-22 20:04 -0700
  Re: Convection is fiction Claudius Denk <claudiusdenk@gmail.com> - 2016-08-21 19:31 -0700

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