Convert the shear probe data - Revision history

CynthiaBluteau: Categorization

2021-11-23T15:33:35Z

Categorization

← Older revision		Revision as of 15:33, 23 November 2021
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	==References==		==References==
	<references />		<references />


			[[Category:Shear probes]]

Rolf: /* Instruments without a differentiator */

2021-11-18T19:28:23Z

Instruments without a differentiator

← Older revision		Revision as of 19:28, 18 November 2021
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	<math> \left\| \frac{H_c}{H_{\Delta}} \right\|^2 = \left[ \frac{2\pi f}{4𝑓_𝑁\, \sin\left(\frac{\pi}{2} \frac{𝑓}{𝑓_𝑁}\right)} \right]^2 \ \ .</math>		<math> \left\| \frac{H_c}{H_{\Delta}} \right\|^2 = \left[ \frac{2\pi f}{4𝑓_𝑁\, \sin\left(\frac{\pi}{2} \frac{𝑓}{𝑓_𝑁}\right)} \right]^2 \ \ .</math>

	This correction factor is approximately <math>1</math> for <math>f\ll f_N</math> and reaches its maximum ~~at the Nyquist frequency, <math>f=f_N</math>, where it equals~~ <math>\left(\frac{\pi}{2}\right)^2 </math>.		This correction factor is approximately <math>1</math> for <math>f\ll f_N</math> and reaches its maximum of <math>\left(\frac{\pi}{2}\right)^2 </math> at the Nyquist frequency of <math>f=f_N</math>.

	-----------------------------		-----------------------------

Rolf: /* Instruments without a differentiator */

2021-11-18T19:25:45Z

Instruments without a differentiator

← Older revision		Revision as of 19:25, 18 November 2021
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	<math> \left\| \frac{H_c}{H_{\Delta}} \right\|^2 = \left[ \frac{2\pi f}{4𝑓_𝑁\, \sin\left(\frac{\pi}{2} \frac{𝑓}{𝑓_𝑁}\right)} \right]^2 \ \ .</math>		<math> \left\| \frac{H_c}{H_{\Delta}} \right\|^2 = \left[ \frac{2\pi f}{4𝑓_𝑁\, \sin\left(\frac{\pi}{2} \frac{𝑓}{𝑓_𝑁}\right)} \right]^2 \ \ .</math>

	This correction factor is approximately <math>1</math> for <math>f\~~ll1~~</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.		This correction factor is approximately <math>1</math> for <math>f\ll f_N</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.

	-----------------------------		-----------------------------

Rolf at 19:20, 18 November 2021

2021-11-18T19:20:01Z

← Older revision		Revision as of 19:20, 18 November 2021
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	The sensitivity of the shear probe to shear is proportional to the square of the speed of profiling.		The sensitivity of the shear probe to shear is proportional to the square of the speed of profiling.
	Thus, one should set a minimum speed for the conversion of the shear-probe data into physical units. Otherwise, the conversion may produce enormously large and quite unrealistic values.		Thus, one should set a minimum speed for the conversion of the shear-probe data into physical units. Otherwise, the conversion may produce enormously large and quite unrealistic values.
	Realistic minimum speeds for the conversion into physical units are <math>0.05</math> to <math>0.1\, \mathrm{m\,s^{-1}}</math> because the shear-probe signal is likely to be dominated by electronic noise and the angle of attack will be large (<math> >20^{\circ}</math>) even for low levels of dissipation.		Realistic minimum speeds for the conversion into physical units are <math>0.05</math> to <math>0.1\, \mathrm{m\,s^{-1}}</math> because for slower speeds the shear-probe signal is likely to be dominated by electronic noise and the angle of attack will be large (<math> >20^{\circ}</math>) even for low levels of dissipation.
	A discussion of the limitations of slow profiling is provided by <ref>Lueck, R.G., D. Huang, D. Newman, and J. Box, 1997: Turbulence measurements with a moored instrument. ''J. Atmos. Oceanic Techno.'', '''14''', 143-161</ref>.		A discussion of the limitations of slow profiling is provided by <ref>Lueck, R.G., D. Huang, D. Newman, and J. Box, 1997: Turbulence measurements with a moored instrument. ''J. Atmos. Oceanic Techno.'', '''14''', 143-161</ref>.

Aleboyer at 03:24, 5 November 2021

2021-11-05T03:24:51Z

← Older revision		Revision as of 03:24, 5 November 2021
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	This correction factor is approximately <math>1</math> for <math>f\ll1</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.		This correction factor is approximately <math>1</math> for <math>f\ll1</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.

	~~======================~~		-----------------------------
	return to [[Flow chart for shear probes]]		return to [[Flow chart for shear probes]]

	==References==		==References==
	<references />		<references />

Aleboyer at 03:24, 5 November 2021

2021-11-05T03:24:19Z

← Older revision		Revision as of 03:24, 5 November 2021
Line 41:		Line 41:
	This correction factor is approximately <math>1</math> for <math>f\ll1</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.		This correction factor is approximately <math>1</math> for <math>f\ll1</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.

			======================
	return to [[Flow chart for shear probes]]		return to [[Flow chart for shear probes]]

	==References==		==References==
	<references />		<references />

Aleboyer at 03:23, 5 November 2021

2021-11-05T03:23:43Z

← Older revision		Revision as of 03:23, 5 November 2021
Line 40:		Line 40:

	This correction factor is approximately <math>1</math> for <math>f\ll1</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.		This correction factor is approximately <math>1</math> for <math>f\ll1</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.

			return to [[Flow chart for shear probes]]

	==References==		==References==
	<references />		<references />

Rolf at 22:27, 14 July 2021

2021-07-14T22:27:41Z

← Older revision		Revision as of 22:27, 14 July 2021
Line 13:		Line 13:
	The sensitivity of the shear probe to shear is proportional to the square of the speed of profiling.		The sensitivity of the shear probe to shear is proportional to the square of the speed of profiling.
	Thus, one should set a minimum speed for the conversion of the shear-probe data into physical units. Otherwise, the conversion may produce enormously large and quite unrealistic values.		Thus, one should set a minimum speed for the conversion of the shear-probe data into physical units. Otherwise, the conversion may produce enormously large and quite unrealistic values.
	Realistic minimum speeds for the conversion into physical units are <math>0.05</math> to <math>0.1\, \mathrm{m\,s^{-1}}</math> because the shear-probe signal is likely to be dominated by electronic noise and the angle of attack will be large (<math> >20^{\circ}</math>) even for low levels of dissipation <ref>Lueck, R.G., D. Huang, D. Newman, and J. Box, 1997, Turbulence measurements with a moored instrument, ''J. Atmos. Oceanic Techno.'', '''14''', 143-161</ref>.		Realistic minimum speeds for the conversion into physical units are <math>0.05</math> to <math>0.1\, \mathrm{m\,s^{-1}}</math> because the shear-probe signal is likely to be dominated by electronic noise and the angle of attack will be large (<math> >20^{\circ}</math>) even for low levels of dissipation.
			A discussion of the limitations of slow profiling is provided by <ref>Lueck, R.G., D. Huang, D. Newman, and J. Box, 1997: Turbulence measurements with a moored instrument. ''J. Atmos. Oceanic Techno.'', '''14''', 143-161</ref>.

	== Instruments without a differentiator ==		== Instruments without a differentiator ==

Rolf at 22:24, 14 July 2021

2021-07-14T22:24:31Z

← Older revision		Revision as of 22:24, 14 July 2021
Line 13:		Line 13:
	The sensitivity of the shear probe to shear is proportional to the square of the speed of profiling.		The sensitivity of the shear probe to shear is proportional to the square of the speed of profiling.
	Thus, one should set a minimum speed for the conversion of the shear-probe data into physical units. Otherwise, the conversion may produce enormously large and quite unrealistic values.		Thus, one should set a minimum speed for the conversion of the shear-probe data into physical units. Otherwise, the conversion may produce enormously large and quite unrealistic values.
	Realistic minimum speeds for the conversion into physical units are <math>0.05</math> to <math>0.1\, \mathrm{m\,s^{-1}}</math> because the shear-probe signal is likely to be dominated by electronic noise and the angle of attack will be large (<math> >20^{\circ}</math>) even for low levels of dissipation <ref>Lueck, R.G., D. Huang, D. Newman, and J. Box, 1997, Turbulence measurements with a moored instrument, J. Atmos. Oceanic Techno., 14, 143-161</ref>.		Realistic minimum speeds for the conversion into physical units are <math>0.05</math> to <math>0.1\, \mathrm{m\,s^{-1}}</math> because the shear-probe signal is likely to be dominated by electronic noise and the angle of attack will be large (<math> >20^{\circ}</math>) even for low levels of dissipation <ref>Lueck, R.G., D. Huang, D. Newman, and J. Box, 1997, Turbulence measurements with a moored instrument, ''J. Atmos. Oceanic Techno.'', '''14''', 143-161</ref>.

	== Instruments without a differentiator ==		== Instruments without a differentiator ==

Rolf at 22:23, 14 July 2021

2021-07-14T22:23:04Z

← Older revision		Revision as of 22:23, 14 July 2021
Line 13:		Line 13:
	The sensitivity of the shear probe to shear is proportional to the square of the speed of profiling.		The sensitivity of the shear probe to shear is proportional to the square of the speed of profiling.
	Thus, one should set a minimum speed for the conversion of the shear-probe data into physical units. Otherwise, the conversion may produce enormously large and quite unrealistic values.		Thus, one should set a minimum speed for the conversion of the shear-probe data into physical units. Otherwise, the conversion may produce enormously large and quite unrealistic values.
	Realistic minimum speeds for the conversion into physical units are <math>0.05</math> to <math>0.1\, \mathrm{m\,s^{-1}}</math> because the shear-probe signal is likely to be dominated by electronic noise and the angle of attack will be large (<math> >20^{\circ}</math>) even for low levels of dissipation ~~(\citet{~~Lueck, R.G., D. Huang, D. Newman, and J. Box, 1997, Turbulence measurements with a moored instrument, J. Atmos. Oceanic Techno., 14, 143-161}).		Realistic minimum speeds for the conversion into physical units are <math>0.05</math> to <math>0.1\, \mathrm{m\,s^{-1}}</math> because the shear-probe signal is likely to be dominated by electronic noise and the angle of attack will be large (<math> >20^{\circ}</math>) even for low levels of dissipation <ref>Lueck, R.G., D. Huang, D. Newman, and J. Box, 1997, Turbulence measurements with a moored instrument, J. Atmos. Oceanic Techno., 14, 143-161</ref>.

	== Instruments without a differentiator ==		== Instruments without a differentiator ==
Line 39:		Line 39:

	This correction factor is approximately <math>1</math> for <math>f\ll1</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.		This correction factor is approximately <math>1</math> for <math>f\ll1</math> and reaches its maximum at the Nyquist frequency, <math>f=f_N</math>, where it equals <math>\left(\frac{\pi}{2}\right)^2 </math>.

			==References==
			<references />