Method and device for testing movement speed
A method for testing movement speed includes, but is not limited to: measuring a static pressure P 0 of an inner cavity of a pressure hole of a mobile device (S 100 ); aligning the pressure hole to a wind direction and measuring a total pressure P of the wind in a static state (S 101 ); aligning the pressure hole to the wind direction in a moving process, and measuring a pressure P m of the inner cavity of the pressure hole in a movement direction (S 102 ); obtaining a current wind speed v f according to a correspondence relationship between a wind speed v f and a dynamic pressure P−P 0 ; and obtaining a current relative movement speed v r according to a correspondence relationship between a relative movement speed v r and a pressure difference P m −P 0 (S 103 ); and obtaining a current movement speed v according to the current relative movement speed v r and the current wind speed v f (S 104 ).
1. A method for testing movement speed, wherein the method comprises:
measuring a static pressure P 0 of an inner cavity of a pressure hole of a mobile device, wherein the pressure hole is in communication with an outside, and is a specifically formed opening or an existing designed opening in the mobile device;
aligning the pressure hole to a wind direction and measuring a total pressure P of the wind in a static state;
aligning the pressure hole to the wind direction in a moving process, and measuring a pressure P m of the inner cavity of the pressure hole in the movement direction;
obtaining a current wind speed v f according to a correspondence relationship between a wind speed v f and a dynamic pressure P−P 0 , and obtaining a current relative movement speed v r according to a correspondence relationship between a relative movement speed v r and a pressure difference P m −P 0 ; and
obtaining a current movement speed v according to the current relative movement speed v r and the current wind speed v f .
2. The method for testing movement speed according to claim 1 , wherein the obtaining a current wind speed v f according to a correspondence relationship between a wind speed v f and a dynamic pressure P−P 0 , and the obtaining a current relative movement speed v r according to a correspondence relationship between a relative movement speed v r and a pressure difference P m −P 0 comprise:
obtaining the current wind speed v f according to the formula
v
f
=
2
(
P
-
P
0
)
ρ
;
and
obtaining the current relative movement speed v r according to the formula
v
r
=
2
(
P
m
-
P
0
)
ρ
;
wherein ρ is air density.
3. The method for testing movement speed according to claim 2 , wherein the method further comprises:
measuring a water vapor pressure e in air and measuring an air temperature T; and
calculating the air density ρ according to the formula
ρ
=
P
R
B
T
(
1
-
0.378
e
/
P
)
,
wherein R B =287.05 J·kg −1 ·K −1 is a gas constant of dry air.
4. The method for testing movement speed according to claim 1 , wherein the obtaining a current movement speed v according to the current relative movement speed v r and the current wind speed v f comprises:
calculating the current movement speed v according to the formula v=v r +v f ·cos θ, wherein θ is an angle of the deviating of the movement direction from the wind direction and in a range of [0°,360°].
5. The method for testing movement speed according to claim 1 , wherein the obtaining a current movement speed v according to the current relative movement speed v r and the current wind speed v f comprises:
in upwind movement, calculating the current movement speed v according to the formula v=v r −v f ; and
in downwind movement, calculating the current movement speed v according to the formula v=v r +v f .
6. A device for testing movement speed, wherein the device comprising:
a pressure sensor, disposed in an inner cavity of a pressure hole of the testing device, wherein the pressure hole is in communication with an outside, and is a specifically formed opening or an existing designed opening in the mobile device; the pressure sensor is configured to obtain a static pressure P 0 of the inner cavity of the pressure hole, and align the pressure hole to a wind direction and measure a total pressure P of the wind in a static state, and measure a pressure P m of the inner cavity of the pressure hole in a movement direction during movement;
a speed acquiring unit configured to obtain a current wind speed v f according to a correspondence relationship between a wind speed v f and a dynamic pressure P−P 0 , and obtain a current relative movement speed v r according to a correspondence relationship between a relative movement speed v r and a pressure difference P m −P 0 ; and
a movement speed acquiring unit configured to obtain a current movement speed v according to the current relative movement speed v r and the current wind speed v f .
7. The device for testing movement speed according to claim 6 , wherein the speed acquiring unit comprises:
a wind speed acquiring module configured to obtain the current wind speed v f according to the formula
v
f
=
2
(
P
-
P
0
)
ρ
;
and
a relative speed acquiring module configured to obtain the current relative movement speed v r according to the formula
v
r
=
2
(
P
m
-
P
0
)
ρ
;
wherein ρ is air density.
8. The device for testing movement speed according to claim 7 , wherein the device for testing movement speed further comprises:
a humidity sensor configured to measure a water vapor pressure e in air;
a temperature sensor configured to measure an air temperature T; and
an air density acquiring unit configured to calculate the air density ρ according to the formula
ρ
=
P
R
B
T
(
1
-
0.378
e
/
P
)
,
wherein R B =287.05 J·kg −1 ·K −1 is a gas constant of dry air.
9. The device for testing movement speed according to claim 6 , wherein the movement speed acquiring unit is specifically configured to
calculate the current movement speed V according to the formula v=v r +v f ·cos θ, wherein θ is an angle of the deviating of the movement direction from the wind direction and in a range of [0°,360°].
10. The device for testing movement speed according to claim 6 , wherein the movement speed acquiring unit is specifically configured to, in upwind movement, calculate the current movement speed v according to the formula v=v r −v f ; and in downwind movement, calculate the current movement speed v according to the formula v=v r +v f .