How do you calculate total head in ground water flow?

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Total head in groundwater flow is calculated by combining pressure head and elevation head, with pressure head representing the height of fluid that would produce the same pressure due to gravity. The formula for head is H = p/(ρg) + (z - z0), where z - z0 indicates the elevation above a reference point. The discussion highlights that pressure is not directly related to water depth in certain contexts, such as in a pressure casserole. It emphasizes the importance of understanding how head is measured and its implications for groundwater flow dynamics. Overall, grasping these concepts is crucial for accurate calculations in hydrogeology.
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Its attached below. I don't understand how you work out the total head. Can someone explain how you do it? I'm really struggling.

I know how to do the elevation, which is just the height above/below the datum level. And I've checked the solutions as well, it seems like you're supposed to work out the total head before the pressure head.
 

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What are the "total head", "pressure head" and "pore water pressure"?
Can you explain that to you grand-mother?
 
maajdl said:
What are the "total head", "pressure head" and "pore water pressure"?
Can you explain that to you grand-mother?

'head' is simply stress (or pressure) mulitplied by depth

for total head is the total pressure as it were
 
Do you think your grand mother could understand?
Could you explain those things in a tangible way?
For example, by comparing what you measure if free water versus water in a soil?

In addition, I don't think that "pressure x depth" is related to the "head".
As I am from Belgium, I am not used with this terminology.
However, I looked at http://en.wikipedia.org/wiki/Pressure_head and it looks like that "pressure head" is the height of fluid that would produce by gravity the same pressure. In some way, it is the pressure expressed in meters of fluid.

In a "Pressure Casserol", the pressure is unrelated to the depth of water insided the "Pressure Casserol". Yet, it can be expressed in head of fluid, and the numerical value might be meters while the "Pressure Casserol" would only be 20 cm high.

See also this picture, where head is shown by the measuring tubes.

320px-Venturifixed2.PNG
 
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The head is defined as H=\frac{p}{ρg}+(z-z_0), where z-z0 is the distance measured upward from the Ordinance Datum z0. So, at points P and C, the head H is 1 meter (there is no flow resistance between points P and C). At point A, the figure shows that the head is 6 meters above the Ordinance Datum. At point B, because the flow is steady, the head is the average of points A and C, or 3.5 meters. The upward seepage velocity is given by:

v=- K\frac{(H_A-H_C)}{(z_A-z_C)}

where K is the hydraulic conductivity (10-4 m/s).
 
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