Center of Pressure
Hydraulics Laboratory
Experiment Report
Name:
Ahmed Essam Mansour
Section: "1", Monday 2-5 pm
Title:
Center Of Pressure
Date:
2nd October, 2006
Objectives:
To calculate the center of pressure of an immersed rectangular surface and compare it to the value calculated theoretical.
Apparatus:
The apparatus is shown diagrammatically in the figure
Note that the curved selection of the shape of this apparatus is to exclude the effect of moments that forces acting on this surface cause about the pivot as all these forces will pass through the pivot.
Theory:
The center of pressure of an immersed body is defined by the vertical distance below the liquid surface.
In this experiment we aimed to find out the center of pressure both theoretically and practically and to compare them after all.
Theoretically, calculations of center of pressure " Hcp" by using the formula 1;
Where;
Hcg: the center of gravity
A: the cross sectional area
I: the moment of inertia
The application of this formula may differ according to whether the body is partially or totally immersed.
Partial Immersion:
Total Immersion:
Practically, the center of pressure will be calculated using the principle of moment equilibrium of the used apparatus about a pivot, only two forces create a moment about this pivot as the apparatus is designed to have a curved surface with the pivot as the center, so that forces exerted on this surface all pass through the pivot and create no moment about it.
The two forces are:
1. Weights of the masses placed on the weight pan, with a moment are equal to 30cm.
W=mg
Where; m: the mass placed in the weight pan (kg) g: the gravitational acceleration (m/s2)
2. Hydrostatic force of the fluid pressure acting on the rectangular plane surface.
F = ρ g A Hcg
Where;
ρ: the mass density of water (1000 kg/m 3 ) g: the gravitational acceleration (m/s2)
A: the cross sectional area of the surface at which the load is acting.
Hcg: the center of gravity of the cross section
By
Experiment Report
Name:
Ahmed Essam Mansour
Section: "1", Monday 2-5 pm
Title:
Center Of Pressure
Date:
2nd October, 2006
Objectives:
To calculate the center of pressure of an immersed rectangular surface and compare it to the value calculated theoretical.
Apparatus:
The apparatus is shown diagrammatically in the figure
Note that the curved selection of the shape of this apparatus is to exclude the effect of moments that forces acting on this surface cause about the pivot as all these forces will pass through the pivot.
Theory:
The center of pressure of an immersed body is defined by the vertical distance below the liquid surface.
In this experiment we aimed to find out the center of pressure both theoretically and practically and to compare them after all.
Theoretically, calculations of center of pressure " Hcp" by using the formula 1;
Where;
Hcg: the center of gravity
A: the cross sectional area
I: the moment of inertia
The application of this formula may differ according to whether the body is partially or totally immersed.
Partial Immersion:
Total Immersion:
Practically, the center of pressure will be calculated using the principle of moment equilibrium of the used apparatus about a pivot, only two forces create a moment about this pivot as the apparatus is designed to have a curved surface with the pivot as the center, so that forces exerted on this surface all pass through the pivot and create no moment about it.
The two forces are:
1. Weights of the masses placed on the weight pan, with a moment are equal to 30cm.
W=mg
Where; m: the mass placed in the weight pan (kg) g: the gravitational acceleration (m/s2)
2. Hydrostatic force of the fluid pressure acting on the rectangular plane surface.
F = ρ g A Hcg
Where;
ρ: the mass density of water (1000 kg/m 3 ) g: the gravitational acceleration (m/s2)
A: the cross sectional area of the surface at which the load is acting.
Hcg: the center of gravity of the cross section
By