Minor losses in pipe flow are a major part in calculating the flow, pressure, or energy reduction in piping systems. Liquid moving through pipes carries momentum and energy due to the forces acting upon it such as pressure and gravity. Just as certain aspects of the system can increase the fluids energy, there are components of the system that act against the fluid and reduce its energy, velocity, or momentum. Friction and minor losses in pipes are major contributing factors. [1] [2] [3] [4]
Before being able to use the minor head losses in an equation, the losses in the system due to friction must also be calculated.
Equation for friction losses:
= Frictional head loss
= Downstream velocity
= Gravity of Earth
=Total length of piping
After both minor losses and friction losses have been calculated, these values can be summed to find the total head loss.
Equation for total head loss, , can be simplified and rewritten as:
= Frictional head loss
= Downstream velocity
= Gravity of Earth
=Total length of piping
= Sum of all kinetic energy factors in system
Once calculated, the total head loss can be used to solve the Bernoulli Equation and find unknown values of the system. [1] [5]
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Hydraulic compressors are a type of compressor that is designed to convert hydraulic power to pneumatic power. It is used across various industries to improve the efficiency of certain types of machinery. Hydraulic compressors have a hydraulic pump to push air through a pipe, which forces a motor to spin. The motor powers the internal air compressor, releasing air in a chamber as a result. Compressors became more popularized in 1799 when Englishman George Medhurst invented a motorized air compressor as a means for propulsion. They have technologically advanced to the point where they can achieve greater force and precision than humans.
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ONE of the fundamental problems of mechanical engineering is that of transmitting energy found in nature, after suitable transformation, to some point at which can be made available for performing useful work. The methods of transmitting power known and practised by engineers are broadly included in two classes: mechanical including hydraulic, pneumatic and wire rope methods; and electrical methods....According to the new system, energy is transmitted from one point to another, which may be at a considerable distance, by means of impressed variations of pressure or tension producing longitudinal vibrations in solid, liquid or gaseous columns. The energy is transmitted by periodic changes of pressure and volume in the longitudinal direction and may be described as wave transmission of power, or mechanical wave transmission. – Gogu Constantinescu
The standard step method (STM) is a computational technique utilized to estimate one-dimensional surface water profiles in open channels with gradually varied flow under steady state conditions. It uses a combination of the energy, momentum, and continuity equations to determine water depth with a given a friction slope , channel slope , channel geometry, and also a given flow rate. In practice, this technique is widely used through the computer program HEC-RAS, developed by the US Army Corps of Engineers Hydrologic Engineering Center (HEC).
