A stagnation pressure probe for droplet-laden air flow

Journal of Propulsion and Power ◽

10.2514/3.22868 ◽

1986 ◽

Vol 2 (3) ◽

pp. 195-196

Author(s):

S. N. B. Murthy ◽

M. Leonardo ◽

C.M. Ehresman

Keyword(s):

Air Flow ◽

Stagnation Pressure ◽

Pressure Probe

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A Stagnation Pressure Probe for Supersonic and Subsonic Flows

Aeronautical Quarterly ◽

10.1017/s0001925900006855 ◽

1974 ◽

Vol 25 (2) ◽

pp. 91-100 ◽

Cited By ~ 2

Author(s):

M J Goodyer

Keyword(s):

Mach Number ◽

Dynamic Pressure ◽

Flow Property ◽

Stagnation Pressure ◽

Pressure Probe ◽

Number Range ◽

Subsonic Flows ◽

Permissible Range ◽

Free Stream Mach Number ◽

Made In

SummaryThe usefulness of a probe which can sense the absolute value of the stagnation pressure in supersonic flow has long been recognised. In the past such a probe has not been available and therefore it has been necessary to infer this fundamentally important flow property from measurements of other properties. This paper describes a probe which has been developed specifically to measure accurately the stagnation pressure of a supersonic gas stream. Measurements of the performance of the probe to date show that it is capable of measuring absolute stagnation pressure with an accuracy of 0.1 per cent in the Mach number range 1.5 to 2.1. No measurements have yet been made in the transonic range, but at low subsonic speeds the probe has demonstrated its ability to measure dynamic pressure within an accuracy of 0.1 per cent at a Mach number of approximately 0.13. The permissible range of misalignment in pitch and yaw before the pressure recovery begins to deteriorate are functions of free-stream Mach number and are usefully wide.

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Development and application of stagnation pressure probe for dusty gas measurements

Review of Scientific Instruments ◽

10.1063/1.1145327 ◽

1995 ◽

Vol 66 (8) ◽

pp. 4356-4361 ◽

Cited By ~ 1

Author(s):

R. G. Batt ◽

M. B. Petach ◽

S. A. Peabody ◽

P. J. Castleberry ◽

C. R. Gallaway

Keyword(s):

Stagnation Pressure ◽

Pressure Probe ◽

Dusty Gas ◽

Gas Measurements

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A Leaf Lamina Compression Method for Estimating Turgor Pressure

HortScience ◽

10.21273/hortsci.45.3.418 ◽

2010 ◽

Vol 45 (3) ◽

pp. 418-423 ◽

Cited By ~ 9

Author(s):

Adonai Gimenez Calbo ◽

Marcos David Ferreira ◽

José Dalton Cruz Pessoa

Keyword(s):

Air Flow ◽

Turgor Pressure ◽

Regression Coefficients ◽

Pressure Probe ◽

Compression Method ◽

Cell Turgor ◽

Detached Leaves ◽

Air Passage ◽

Quantitative Procedure ◽

Probe Measurements

A portable wiltmeter instrument to estimate leaf turgor pressure according to an adaptation of the flattening method was developed. In the instrument, a flexible inflating membrane presses the leaf against a flattening plate having small orifices surrounded by a finely engraved network of obtuse indentations through which air flow is delivered. During a measurement, as the compression builds up, the leaf is progressively molded against the flattening plate, and as a consequence, the air flow (x) crossing the plate is reduced toward zero. The smallest leaf compression (p0) that blocks the air passage is an estimate of the leaf turgor. Wiltmeter measurements were compared with pressure probe measurements of cell turgor pressure in detached leaves of lettuce (Lactuca sativa L.), kale (Brassica oleracea L. var. Acephala), and chicory (Chichorium endivia L.), which were allowed to suffer diverse levels of wilting caused by transpiration. Such observed wiltmeter readings were a little lower than the cell turgor pressure measured with a pressure probe; the regression coefficients between these methods were: 1.156 for lettuce, 1.13 for kale, and 1.036 for chicory. This portable quantitative procedure to measure leaf firmness has potentially valuable applications related to postharvest and field plant physiology studies.

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