## Steady flow

Steady flow: the velocity of a fluid particle changes with the position.

In the field of steady flow, devices are particularly suited to teaching measurement of the flow course, pressure distribution and velocity distribution.

Cylinder in transverse incident flow; record pressure distribution in the wake of the cylinder in conjunction with HM 240.03

##### Learning objectives / experiments

in conjunction with HM 240

- measurement of the pressure distribution around a

cylinder subject to transverse incident flow

in conjunction with total pressure sensor HM 240.03 - measurement of the total pressure in the wake of a

….

Measurement of pressure losses in straight pipe sections, in a 90° pipe bend, and in a 90° pipe angle

##### Learning objectives / experiments

in conjunction with HM 240

- measurement of pressure losses in
- straight pipe sections
- a 90° pipe bend
- a 90° pipe angle

….

Investigation of heat transfer from a heated rod to an air flow

##### Learning objectives / experiments

in conjunction with HM 240

- recording a cooling curve
- determining the heat transfer coefficients from the

cooling curve

Measurement of the velocity distribution in the intake tube on HM 240

##### Learning objectives / experiments

in conjunction with HM 240

- measurement of the total pressure and the static

pressure in HM 240’s intake pipe - recording pressure distribution over the cross

section

….

Determining the critical Reynolds number

##### Learning objectives / experiments

- measurements of the pressure loss in laminar flow
- measurements of the pressure loss in turbulent flow
- determining the critical Reynolds number
- determining the pipe friction factor
- comparing the actual pipe friction factor with the

….

Determining the fan characteristic curve

##### Learning objectives / experiments

- recording a fan characteristic

in conjunction with the power meter HM 240.02 - determining the fan efficiency

in conjunction with corresponding accessories - velocity distribution in the pipe

….

Experiments on water flow in open flumes and in pipes. Transparent design allows observation of the flow processes.

##### Learning objectives / experiments

- fundamentals of pipe flow and open-channel flow
- differential pressure measurement at the orifice,

Venturi nozzle, pipe bends and pipe angles,

contraction and enlargement - investigation of weir structures in an open channel

….

Determining pressure loss and velocity profiles; different measuring objects

##### Learning objectives / experiments

experiments in the field of steady, incompressible flows by means of different measuring objects:

- calculation of the flow rate and the flow velocity
- recording the different velocity profiles in both the

free jet and the pipe cross-section - representation of the pressure loss in the system

….

For experiments from the fields of flow around bodies and steady incompressible flow

##### Learning objectives / experiments

together with appropriate accessories: experiments from the field of flow around bodies

- velocity measurement of flows with Pitot tube
- boundary layer analysis on a flat plate with flow

along the plate - drag of bodies

….

Demonstration of the continuity equation and Bernoulli's equation

##### Learning objectives / experiments

- investigation of the continuity equation and

Bernoulli’s principle - determination of the dynamic pressure from the

measurement data via Bernoulli’s principle - calculation of the flow velocity from the

….

Investigation of the flow through a pipe bend

##### Learning objectives / experiments

- investigation of the pressure curve at a 90° pipe

bend - determination of the static pressure at 29 pressure

measuring points - representation of the pressure distribution

In gases there is a difference between flow at constant volume (incompressible) and flow with varying volume (compressible). For larger changes in the fluid’s pressure and temperature the interconnections between pressure, temperature and volume may not be ignored any more. This flow is called compressible.

Subsonic and transonic flow through different measuring objects

##### Learning objectives / experiments

- pressure losses in pipes and pipe elbows
- flow in convergent/divergent nozzles
- supersonic flow in the de Laval nozzle
- determine the speed of sound in air
- compare calculation methods for incompressible

….

Schlieren optics for visualisation of Mach lines and shock waves on drag bodies; interchangeable walls in the measuring section produce velocities up to Mach 1,8

##### Learning objectives / experiments

- pressure curves in supersonic nozzles (Laval

nozzle) - pressure curves and losses in tunnel flows with

Mach > 1 - observe shock waves in drag bodies using

….

Measuring the impact or thrust force for determining the discharge velocity and the nozzle efficiency

##### Learning objectives / experiments

- determining the critical pressure ratio
- demonstration of the “choking effect”
- determining flow velocity in the narrowest cross

section - measurement of the reaction or action force of the

….

Measuring the pressure curves in a convergent nozzle and in Laval nozzles and to study the flow of compressible fluids

##### Learning objectives / experiments

- pressure curve in
- de Laval nozzles
- convergent nozzles

- connection between inlet pressure and mass flow

rate or exit pressure and mass flow rate

….

Pipe systems are generally used to transport fluids. When flowing through a pipe the friction causes the pressure energy of the fluid to fall and the internal energy of the fluid to increase.

Pressure losses in various pipe fittings and in the ball valve

##### Learning objectives / experiments

- investigate pressure losses at segment bend and

bends - investigate pressure loss at contraction and

enlargement - pressure loss at a ball valve and determination of a

….

Influence of flow velocity on pressure loss

##### Learning objectives / experiments

- pressure losses in pipes, piping elements and

fittings - how the flow velocity affects the pressure loss
- determining resistance coefficients
- opening characteristics of angle seat valve and gate

….

Investigation of flow and pressure losses in different pipe sections

##### Learning objectives / experiments

- different methods of differential pressure

measurements - influence of pipe diameters, different materials and

surface roughness - effect of the flow velocity

….

Interchangeable measuring objects and different pipe sections

##### Learning objectives / experiments

- flow and pressure measurement methods
- function of nozzle, orifice, Venturi nozzle
- losses due to pipe bends and pipe angles,

changes in cross-section and shut-off valves and

fittings

….

Experimental determination of important coefficients related to pressure loss in various pipe systems

##### Learning objectives / experiments

- fundamentals of flow measurement
- fundamentals of pressure measurement
- determination of the friction factor for different pipe

materials and diameters - resistance coefficients of pipe bends, enlargements

….

Pressure losses at various piping elements and pipe networks; parallel and series connection of pipe sections

##### Learning objectives / experiments

- recording the calibration curve for pipe sections:

pressure loss over flow rate - pipe sections connected in parallel
- pipe sections connected in series
- combined series and parallel connection

….

Investigations on centrifugal pumps, control valves, piping and fittings. Large scale industrial components and high-quality instrumentation deliver realistic measurement results.

##### Learning objectives / experiments

- experiments with pumps, valves and fittings and

pipe sections - operating behaviour of centrifugal pumps in

individual or parallel operation - measurement of the NPSH value of pumps

….

Investigation of the pressure difference in four equal-length pipe sections made of different materials

##### Learning objectives / experiments

investigation of the pressure losses of flow through pipes

- measurement of the pressure differential on

different pipe sections - influence of various pipe diameters
- influence of different materials and surface

….

Investigation of the pressure loss at pipe elements with different changes in pipe direction and materials

##### Learning objectives / experiments

- flow measurement
- differential pressure measurement
- effect of flow and surface roughness
- effect of the flow velocity
- effect of changes in pipe direction

Investigation of the pressure loss of standard valves and fittings

##### Learning objectives / experiments

- pressure losses in valves and fittings
- measuring the pressure difference
- effect of the valve orifice shape on the pressure loss
- effect of the flow velocity
- determination of resistance coefficients

….

Investigation of pressure losses at contractions, pipe angles, pipe bends, valves and fittings and pipe elements

##### Learning objectives / experiments

- pressure curve in a closed pipe system with

circulation pump - influence of pipe diameter, flow velocity, change in

cross-section and pipe fittings on the pressure

losses

….

Determining the pressure loss in an open pipe section

##### Learning objectives / experiments

- hydrostatic pressure
- flow pressure
- pressure loss
- representation of pressure curves

Special emphasis on technical issues:

- constructions

- valve characteristics

- Kvs values

Design and function of control valves; determination of the Kv value

##### Learning objectives / experiments

Together with control valves RT 390.01 – RT 390.06

- demonstration and functional testing of control

valves - determination of Kv and Kvs values
- plotting valve characteristics

….

Recording characteristic curves of industrial fittings and a centrifugal pump

##### Learning objectives / experiments

- characteristics of a centrifugal pump
- behaviour during operation and function of
- ball valve
- butterfly valve
- shut-off valve

….

When liquids flow, flow processes may cause local pressures that are smaller than the corresponding vapour pressure of the liquid. In this case, the liquid evaporates and vapour bubbles are formed. When the pressure re-increases the vapour bubbles implode.

Visualisation of cavitation effects in a transparent pump; how speed, inlet pressure, flow rate and temperature affect cavitation

##### Learning objectives / experiments

- formation of cavitation
- observation of cavitation effect
- how speed, inlet pressure, flow rate and

temperature affect cavitation

Investigation of cavitation process in a venturi nozzle

##### Learning objectives / experiments

- function of a Venturi nozzle
- pressure as a function of the flow rate
- cavitation processes at different flow rates and

pressures

Open-channel flow involves, amongst other things, the management of watercourses for the purpose of navigability, damming of lakes for power generation and/or storage of drinking water and flood protection measures.

Discharge measurement in open channels using two measuring weirs

##### Learning objectives / experiments

- free overfall at the sharp-crested weir
- plate weirs as measuring weirs
- determining the discharge coefficient
- comparison of measuring weirs (Rehbock,

Thomson)

….

Flow around various drag bodies and incident flow of weirs; ink as contrast medium

##### Learning objectives / experiments

- how differently shaped weirs affect the flow
- visualisation of streamlines for flow incident to a

weir - visualisation of streamlines when flowing around

various drag bodies

Flow processes on different structures in open and closed channel flows

##### Learning objectives / experiments

Open channel

- flow over control structures: broad-crested weir,

narrow-crested weir, ogee-crested weir with ski

jump spillway, sill - discharge under a gate

….

Experimental section for performing flow experiments in open flumes with lengths of 2,5m or 5m available, closed water circuit and inclination adjustment

##### Learning objectives / experiments

Together with optionally available models

- uniform and non-uniform discharge
- flow formulae
- flow transition (hydraulic jump)
- energy dissipation (hydraulic jump, stilling basin)

….