Units Three and FiveUnits Three and Five

Energy Transmission Using Energy Transmission Using FluidsFluids

Both Liquids and Gases qualify as fluids since each takes the shape of its container and will produce flow.

However, gases compress and liquids are relatively incompressible.

Liquids and GasesLiquids and Gases

A molecule consists of two or more atoms in A molecule consists of two or more atoms in chemical combination.chemical combination.

Liquid MoleculesLiquid Molecules Gaseous Gaseous MoleculesMolecules

Molecular EnergyMolecular Energy

Molecular energy is the movement of Molecular energy is the movement of molecules within a substancemolecules within a substance

Molecular energy is affected by temperature.Molecular energy is affected by temperature.

Fluids take the shape of their Fluids take the shape of their containerscontainers

Gases and Heat EnergyGases and Heat Energy

Gas Temperature, Pressure, Gas Temperature, Pressure, Compression, and InefficiencyCompression, and Inefficiency

Boyles Law of Gas CompressionBoyles Law of Gas Compression

Hydraulic Transmission of EnergyHydraulic Transmission of Energy

Pneumatic Transmission of EnergyPneumatic Transmission of Energy

Hydraulic AccumulatorHydraulic Accumulator

Positive Displacement PumpPositive Displacement Pump

Positive Displacement CompressorPositive Displacement Compressor

Pump TypesPump Types

1. Gear

2. Piston

Pump TypesPump Types

3. Vane

Pump TypesPump Types

Resistance and PressureResistance and PressureAny influence that restricts the movement of fluid is Any influence that restricts the movement of fluid is resistance and will effect pressure. resistance and will effect pressure.

The systematic relationship between resistance The systematic relationship between resistance and pressure is directly proportional.and pressure is directly proportional.

Heat generation in FluidsHeat generation in Fluids

When energy is consumed to overcome resistance, When energy is consumed to overcome resistance, energy changes form. The energy is transformed energy changes form. The energy is transformed into heat energy.into heat energy.

Examples:Examples:

Heat from lightingHeat from lighting

Heat from machine bearings.Heat from machine bearings.

Heat from friction Heat from friction

ViscosityViscosity

Viscosity is the measure of a liquids resistance to Viscosity is the measure of a liquids resistance to flow.flow.

As a “liquid” takes on heat, its viscosity will As a “liquid” takes on heat, its viscosity will change.change.

Measuring ViscosityMeasuring Viscosity

Viscosity is measured in units called Saybolt Universal Viscosity is measured in units called Saybolt Universal Seconds or SSU. Seconds or SSU.

This is the time it takes for a liquid to flow through an This is the time it takes for a liquid to flow through an orifice of a exact size when the fluid is at a certain orifice of a exact size when the fluid is at a certain temperature.temperature.

Viscosity and Friction Viscosity and Friction generate Heatgenerate Heat

A liquid resists movement, this is resistance.

A sharp bend or turn is resistance.

Fluid moving too fast through through a conductor generates heat because of resistance.

The rate of movement of fluid per foot is referred to as velocity.

Viscosity and Friction Viscosity and Friction generate Heatgenerate Heat

(continued)

Maximum velocities for fluidsMaximum velocities for fluids

Oil: 10 to 30 feet per second depending on pressure. 15 fps is a general rule.

Womack, Vol1, page 37.

Gas: 1100 fps, “critical velocity.”

For oil velocity: GPM x .3208/AreaFor oil velocity: GPM x .3208/Area

Pressure DifferentialPressure Differential

When ever a fluid is moving through a conductor When ever a fluid is moving through a conductor and there exists a difference between pressure and there exists a difference between pressure between any two points, the difference is called a between any two points, the difference is called a pressure differential or “delta-P.”pressure differential or “delta-P.”

General System DesignGeneral System Design

Avoid sharp turns, obstructions, and anything Avoid sharp turns, obstructions, and anything that would disturb flow.that would disturb flow.

Also consider pipe size.Also consider pipe size.