Hydraulic head and tank calculator

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Need to calculate pump power, verify flow velocity in a pipe, or correctly size a hydraulic tank in seconds?
SizerAxoPro simplifies complex engineering on a single platform. Enter your flow rate, diameter, length, and operating times, and get a complete analysis of your system.

Our tool allows you to evaluate pumping power, flow velocities, suction geometry, and tank capacity, incorporating a detailed, step-by-step calculation report. This lets you validate each variable, from unit conversions to the applied hydraulic and regulatory criteria, helping to ensure your projects operate within safe ranges, reduce the risk of erosion, cavitation, vortices, or water hammer, and comply with good engineering practices.

Tabla de materiales para el coeficiente C (Hazen-Williams)

In fluid engineering, correctly sizing a pumping system not only ensures operability but also optimizes energy consumption and extends equipment lifespan. To achieve this, the fundamental concept we must master is Total Dynamic Head (TDH).

Total Dynamic Head (TDH) is the total amount of pressure (measured in meters of water column) that a pump must overcome to move a fluid from the suction point to the final discharge point at a given flow rate.

It is not just the physical height to which we want to raise the water; it is the sum of all the resistances the system offers to the fluid's movement.

To accurately calculate TDH, our SizerAxoPro tool breaks down the energy into three main components:

1. Static Head (Z)
This is the net vertical elevation difference between the liquid level at the source and the highest discharge point. It is the minimum potential energy required, regardless of whether the fluid is moving or not.

2. Friction Losses in Pipes (hf)
When water flows, it rubs against the internal walls of the pipe, generating heat and losing pressure. SizerAxoPro uses the Hazen-Williams Equation, the industry standard for clean water:

L: Pipe length.
Q: Flow rate.
C: Roughness coefficient (depends on the material, e.g., PVC = 150).
D: Internal diameter.

3. Minor or Singular Losses (hm)
These are pressure drops caused by turbulence when passing through fittings such as elbows, valves, filters, or reducers. They are calculated using resistance coefficients (K):

Where v is the fluid velocity and g is the acceleration due to gravity.

How do we calculate the Required Power?

Once we have obtained the Total Dynamic Head (TDH = Z + hf + hm), we determine the power that the pump motor must deliver (in Horsepower - HP) using the following formula:

ρ: Fluid density.
ŋ: Pump mechanical efficiency (generally between 0.60 and 0.85).

Design Recommendations in SizerAxoPro

When using our tool, pay attention to the Flow Velocity:

Velocity < 0.6 m/s: Risk of sedimentation (low self-cleaning).
Velocity 1.5 - 2.5 m/s: Optimal operating range.
Velocity > 3.5 m/s: High risk of erosion, excessive noise, and water hammer damage.

SizerAxoPro Tank is a technical tool designed for the hydraulic pre-sizing of pumping tanks, geared towards engineers, designers, and hydraulic systems specialists.

The application allows for a quick and clear evaluation of the minimum required tank capacity, considering the operating flow rate, retention time, and a configurable safety factor. It also analyzes the suction geometry, calculating the fluid velocity in the suction pipe and comparing it to the limits recommended by international standards such as API 610 and Hydraulic Institute (HI 9.6).

Its main functions include:

Calculation of the effective and total tank volume
Evaluation of suction velocity with alerts for safe, high, or critical ranges
Determination of the recommended suction diameter for a given design velocity limit
Estimation of the minimum submergence required to reduce the risk of vortices and air ingress
Clear presentation of the mathematical development and technical criteria used

SizerAxoPro is intended as a preliminary engineering tool, ideal for conceptual analysis, comparison of alternatives, and technical-commercial support. The results do not replace a detailed hydraulic design or specific NPSH verifications, but they provide a solid and consistent basis for early decision-making in pumping projects.