The well known Transparent
engine coupled with our power absorber and equipped with our systems explains
the internal combustion process of a 4-stroke Otto engine better than anything.
Newly equipped it matches the requests on explaining the future automotive
the internal development of power
VVA (Variable valve actuator)
demonstrates the valve control timing
Controlling the intake fuel
injection allows profund studies of the influence of mixture
Varying igition timing and
dwell makes these influences transparent
Fully variable valves actuation –
timing and lift – for a laboratory
4-stroke internal combustion engine for the practical education.
The 4-stroke engine which is well known for many years
in laboratory practice was equipped with a piezo-pneumatic valve actuator.
The performance is controlled with the mouse pointer of the PC during
running. The engine is incorporated in a test rig whose control, data
acquisition and data display is exclusively executed on the PC. The real-time
data acquisition includes the permanent indicating with displaying in
p/V or p/? - diagram and with the calculation of the averaged indicated
1. The engine
The engine base is a mono-cylinder with 70 ccm stroke
volume and a compression ratio of 1:4. The cylinder wall is glass. The piston
runs dryly. The connection-rod bearings are dryly running needle rollers.
The transparent design of the engine allows observation of crankshaft, piston,
valves, ignition and combustion.
The usable speed range is between 350 and 2500 rpm. The hanging valves are
directly operated by cup-like pneumatic pistons
(Figure 1). The auxiliary pressed air flow is conducted by a way-valve that
is driven by a piezo-actuator. The high flow-rate of this fast way-valve
makes this functionality possible.
The mixture is made by an injection pump in the intake. The pump performs
a mono-stroke of adjustable height, driven by a piezo-actuator. Partial
load is preferably executed by “Early intake valve closure”
or “Late intake valve closure”, but it is also possible to activate
one throttle situation in
the intake for comparison.
Reducing the pressure of the auxiliary air from 2,8 down to 2.0 bar effects
a reduction of the valve lift and thus a reduction of the time opening square.
The electronic ignition is also fully variable in terms of timing and dwell.
The upper panel of the software screen contains the control elements (Figure
2) : A status- and a speed shifter control the engine performance.
The engine needs a high resolution field of characteristic data sets for
all operation conditions. These have to be elaborated by the student and
are saved as data files. With loading of such a data file the engine is
immediately driven into the operation point, including the set speed. The
control elements for saving and loading can be found in the control panel
of the screen. (Figure 2).
2. The test rig
Important part of the test rig is the directly coupled
electric motor/generator. A special elastic shaft joint governs the extremely
disharmonic force transmission of the mono-cylinder. The electric motor/generator
is in swivel bearings and has got a torque adaptor which is combined with
a force sensor. The electric engine governs the combustion engine and functions
as power absorber and engine starter.
The engine needs an additional piston cooling by an air ray similar to the
piston cooling with oil spray. This is automatically controlled by the test
stand depending on exhaust temperature and power. The exhaust gas is cleaned
by a special catalytic converter. A fan leads the exhaust gas through a
pipe and a flex hose to the outside.
3. Measured quantities
Force sensor at the swivel support
Encoder on the crankshaft
Directly calculated from the injection pump
stroke and the speed
Exhaust gas temperature
Thermocouple in the exhaust unit
Ox. probe voltage
Intake air flow
Differential pressure measurement on nozzle
Internal cylinder pressure
Cooled sensor on cylinder head
Encoder 100 Imp./rev. and UDC on the crankshaft
The data acquisition captures 40 samples of each non-indicated
measured quantity per revolution. The quantities value is equal to the
arithmetic average. The resolution for the indicator diagram is 200 values
per power cycle. The control timing actions are refreshed 400 times per
4. The measuring display
All measured quantities as well as the derivative
quantities power, specific fuel consumption and average internal pressure
are displayed by bargraphs. A fast refreshing table displays all quantities
as exact digitals. All values can be selected for plotting. An extraordinary
feature is the test stand's indicator mode which works simultanously to
all other functions. The data is displayed on a software-oscilloscope. Figure
3 shows a minimized p/alpha-diagram and an enlarged one in figure 5. The
indicator diagram can be configured as p/? or p/V diagram with optional
focus on the gas exchange phase ((Figure 7).
Not only the internal cylinder pressure is indexable, but also torque, intake
air flow and voltage of the oxygene probe. ((Figure 4 u. (Figure 6)
Indicator diagrams can be saved with the indicator diagram browser, presenting
the recently captured diagrams for further evaluation. Stored data files
includes the values of all quantities, especially the control timings. A
powerfull export function provides easy export to external software. The
software package includes powerfull functions for the post editing of recorded
data and preconfigured evaluation templates (Figure 8).
Finally The test stand is called „Engine technique
stand“ to demonstrate, that it presents the final modern technologies
on a small base of 1 m²: Fully variable valve actuation in combination
with extraordinary operation and data acquisition including indicating
Keywords: engine dynamometer, engine test
cell, engine tester, engine test stand, testcell, motor tester, engine
test software, power tester, transparent engine, 4-cycle engine, oil-free
engine, engine test stand,power absorber, internal combustion test bed,
4-cycle engine trainer, automotive education, Valvetronic, Transparent
Engine Technique Stand,fully variable valve actuator, monocylinder 4-stroke
Otto, transparent cylinder, crankshaft, piston, valves, ignition, combustion,
different fuels, intake injection,Injection volume, timing are fully variable
adjustable, intake, outlet, open,close, valve lift, time opening square,
electronic ignition, free variable, dwell, cathalyst, intake airvolume,
exhaust tubing, oxygene probe exhaust gas temperature, rendered torque,
force sensor, sviwel support, rollable stand, ignite, inject,air fuel
mixture, rich, poor, fuel injection, ignition and valves timing, ignition,
early, late, inlet outlet valve overcross, Indicating mode, internal cylinder
pressure, intake valve, outlet valve, compress, cold start, warm up, injection
quantity, Compression curve, long ignition delay, Late intake closure,inflammation,
Early intake closure, fluid condensation, specific fuel consumption, stoichiometric
mixture, variable valve actuator, throttle, Partial load, early inlet
valve, late inlet valve close, gas exchange phase, indicating aspirated
air flow, indicating torque, 4 stroke engine, effect of ignition, valve
lift, vva, VVA
First internal combustion engine to be operated as 4-stroke and 2-stroke
View of the engine with intake and tube leading to the accu volume for the flushing, valves actuator, there behind piezopump with inbuilt pressure sensor for the indicating, still ignition, -probe, thermocouple, cooling fan left, exhaust gas fan in background
The small engine for laboratory practice, which is already famous for its fully variable valves actuation , was redesigned so that it can be operated either in 4-stroke or in 2-stroke mode. This is possible, because all its functions are controlled completely electronically. The new direct injection, which was realized with the reinforced piezopump, allows injection into compression stroke after ending of the flushing phase. Flushing is made by the correct setting of the valves open phase around LDC and with flushing air which is taken from the pressed air supply, always used with the engine. Control and data acquisition is done from PC screen same like before. Also loading and saving of data sets of performance conditions like coldstart, fulload800, partialload800 etc. are done same way as before during running. So can be switched completely freely also between 2-stroke and 4-stroke data sets. Flushing air supply however should be disconnected in 4-stroke mode. Otherwise the engine would be overcharged.
Regarding this the new design provides not only the 2-stroke operation but also the overcharging of the engine.
Screen with: In headlines control diagram for IVO-IVC, Injection ON-OFF, Ignition ON-OFF, OVO-OVC etc. Bargrafhs for measures, plotter as small display.
Indicating as big display P/V 20 plots for saving selection
Hydrobrake 100 kW / 6000 rpm in
sectioned version is an engine test-
system for easy coupling of different engines.
Coupling by means of a plug-in flexible shaft
Frame connection by two bolts
Cooling water connection with thermostate of the brake
Fuel supply by TeLC fuel Consumption Meter
Load- and power control from brake panel or PC
Display in panel for direct indication of Torque,
Revs. and fuel consumption
Remote power and load control from PC
Control and data acquisition by serially connected
Indicating and other options
engines, which are only operated under idling conditions , can easily
for power- and consumption testing.
Modification of Functional
Water / water heat exchanger with tube connection
with water supply or brake
plug-in flywheel adaptor for flexible coupling shaft
power controller is connected with the remote control
drive of the brake
fuel supply tubes are connected with the TeLC fuel
test- and Control- Software
Serially connected external PC allows control and data acquisition (see
TeLC Engine-Test- and Control- Software)
Engine power is controlled with mouse shift with help of a positioning
drive. Setpoint of speed is also set with mouse shift and kept constant
with automatic controller.
Dissipating heat and power are transmitted to cooling water, controlled
by automatic thermostate.
Keywords: Engine test cell, Engine test stand,
Engine test bed, automotive education, 4-cycle engine, 4-stroke engine
Engine test cell "Tandem 100kW / 6000 Rpm" includes a Diesel and a Gasoline engine, the one or other connectible with the power absorber just on knob-turn, so providing fast and profund comparison of both engine types with no need of resetting work.
Measurement not only of power and fuel consumption but also:
Exhaust gas temperatures
Energy losses by engine cooling
Average indicated pressures
Indicating graph as p-alpha and p-V- form
Tandem is controlled by PC.
Specialties: The measuring devices are digitally connected to the
internal controller, sending data to an external PC. Stand control and data
acquisition is performed by Windows-software. Measured quantities are:
Hydraulik brake 200 Nm created at lowest speeds
Installed engines ready for use
Movability and changeability also after combination at place
Starting and connecting of resp. engine by ignition turnkey
Closed engine cooling by means of heat exchanger against fresh water
Fuel supply through TeLC Fuel Consumption Meters
Display on operator panel for direct reading of torque, speed and fuel consumption
Control values readable from the original car combi Instruments
air-cooled engine test stand providing high measuring accuracy, maximum
safety and clear build-up. It needs no supply like cooling water
and therefore allows fast and easy start-up. It is available with Diesel
and Gasoline engines, working in 2 or 4 stroke process. A special feature
is the inbuild indicating system. Data acquisition and processing will be
performed by our powerful engine software
The measuring devices are digitally connected to the
internal controller, sending serial data to an external PC. Stand control
and data acquisition is performed by Windows-software. Measured quantities
Engine test stand software
for the Windows operating systems 95/98/NT/2000/ME/XP
This software is made for the data acquisition on
TeLC engine test stands
The instruction manual is readable with the Internet
The simulation mode allows training on the software
without a connected test stan
Bars, plotter and tables display measured, derivated
quantities and filled in technological data
Different preconfigured test evaluation templates
Powerful functions for post data editing
Total view includes
plotter, bars and small oscilloscope to view the
p/V (alpha) -chart. The contol window for the fully variable valve actuator
is visible on top.
The following quantities are measured, recorded and displayed: Torque,
speed, fuel consumption, exhaust gas temperature, oxygene probe voltage,
inicated pressure optionally cooling water temperature and flows.
The following quantities are derivated, recorded and displayed: Averaged
indicated cylinder pressure, specific power and specific fuel conspumption,
with large oscilloscope, presenting the p/V,( p/alpha)-chart and small plotter
for other quantities.
The oscilloscope-presentation is fast refreshing, depending on computer-performance
up to 20 times per second. Each combustion-cycle is captured.
An indicator diagram browser allows confortable data storage to disk.
This test evaluation, shows multiple p/alpha-charts
with different ignition timings.
This universal fuel consumption meter
of high accuracy can be used with gasoline and diesel engines. Supply
systems having fore- and back flow are connected with quick connectors
and if needed supplied by the built-in fuelpump.
The unit includes the reservoir of 10L ( 20L ). Measuring
principle is precision time measurement of a down flowing volume.
The LC- display indicates the current and the average consumption in L/h.
Serial data interface with protocol description
Software for fuel consumption
Analog output 4-20mA
Connection with external tank
Measuring range: 0.01 - 1 L/h and 0.5 - 40 L/h;
Power supply: 12 V DC
Functional Engines are
the necessary training object for automotive service technicians. With
help of the test- equipment engine functions are verified, faults are
found and can be repaired. All components are close together and easy
Included systems are complete for engine operation.
Multifunctional instrument, ignition key, starter,
generator and battery
Water cooling with original radiator are installed,
charger intercooler and oilcooler mostly are not, while the sensors
belonging to the system do exist
Exhaust system and catalyst etc. in shorted form
Fuel supply as originally f.e. with tank pump
Accelerator pedal mostly direct or with ist electric
Faults insertion box:
Faults insertion box with 8 faults interrupt, short
break or shorten to body depending on well known disturbances of the
Better Training in Automotive Practice workshop to match the skill requests modern engine electronic equipment demand. TeLC developed FuMoControl a new scope on training engine control electronics.
Main features of FuMoControl are:
Trainee can use foremost his Windows-PC
Screen contains all he needs: Wiring scheme, oscilloscope, cable connections, faultgenerator, report
Working methods are virtually but on the loop which means really connected with the engine control circuits
OBD signals can be read all the usual procedures can be executed
Actions are possible: ignition on, start engine, operate accelerator
PC´s can be connected in a network, trainer has got interaction- and control rights
Engine electronics are protected optimally
Multiple workingplaces are installed on one single engine
Maximal 128 faults can be switched on commanding the unit on the engine
Multiple categories of faults are generated: cable break, cable miscontacting (resistance), unlogical value (defected sensor), hasardous misfunctions under vibrations, heat or current loads (cold junction)
Report: test steps of the trainee are documentated
On the engine support contains the control- , switching and communication unit with terminals(RS232, USB, Ethernet) as well as an LCD and a navigation- turnknob for the execution of basic functions.
Following pictures show screen displaying, saving actions and Scheme
Fault setup and trainee supervisor view of FuMoWin32 Software
Electrification of vehicle drives is coming up more and more. The battery is the most important object. Till today weight of the enery content is 10 times of that with gasoline. And the costs are a lot. Energy balance is only then ok if charging current is generated by regenerative means. All these developments are going on. If the battery is heavy then the vehicle itself must be eased, new material is being developped for that purpose.
Training of vehicle experts is needed for the fundamentals of this new technology. TeLC want to help here with ist new teststand.
Torque engines of any kind can be coupled to the receptor flange on the platform. One direct and one geared drive belong to the equipment. The flange is coupled with a three phase engine by means of a Poly-V-beltdrive
Three phase engine is equipped with variable speed control.and torque measurement. Power of that engine is as high to govern the speed.
LC display on the cabinet indicates measure values T, v, V, C, Pm, Pel, c , turning-increments, Vcontr.. Serially connected to computer, data acquisition can be made with TeLC software
One part of the cabinet can be opened from behind. This allows access to in- and outputs of the controller with help of external instruments like multimeter or oscilloscope.
Technical data of the teststand:
motor power up to 600W
torque max. 60 Nm
speed max 400 rpm
brushless test engines with external / inbuilt controller
Braking powers (recuperation)
The operational functions on the teststand:
Multifunctional control wheel for speed governing by the 3-ph.motor and switching drive / brake function and diagnosis
Battery discharging / charging
On/off controller torque-engine
3+5 socket motor connection
display clamp and power regulator
Braking with the torque engine
Torque characteristic versus speed
Current consumption / reach at different loads
Braking performance and recuperation
Charging performance of batteries
Discrete Measurement on in- and outputs of the controller
Part of the cabinet can be opened from behind. Controller, charger, battery and all connectors are visible and accessable. With help of external measure instruments status, voltages and currents can be measured.
TeLC software: Acquisition screen as process image or as plotter see below.
Included are remote control and switching functions.
Reports of some typical tests
Multiple data files can be plotted with predefined graphs..Data were concentrated (edited) Tableform data export f.e. to Excell is provided