Engine Emissions Heavy Duty Testing & CalibrationFor Heavy Duty certification only the engine is tested on an engine test bed. Two different test types exist - a stationary and a transient test.
For the European emission regulations both test types exist. Up to the Euro II regulation (inclusive) and for all diesel engines in Euro III a stationary test cycle is used. For advanced diesel engines (with De-NOx Cat and / or particulate traps) in addition a transient test must be performed (starting with Euro III). Gas powered engines will be tested only in a transient test for Euro III. For USA heavy duty applications a transient test type must be performed. For Japan heavy duty applications a stationary test type must be performed.
The test bed can also be used for advanced R&D tasks such as engine mapping and calibration of the engine control unit, where emissions measurements are needed.
Emissions Measurement Systems & Instruments
Optimization Tools
Demands on the Test BedThe complexity and demanded accuracy of heavy-duty emissions applications puts high demands on the test equipment. Such demands include:
 | High degree of automation e.g. for 24 hour tests | | For transient certification testing, highly precise control of the dyno and the unit under test | | Ability to generate a large amount of accurate test data based on many measurement points | | Automatic calibration of the emissions analysis systems – essential for accurate measurement | | Integration of a wide variety of instrumentation and peripheral equipment | | At least 2 interfaces to the engine electronics | | Particulate instrumentation for ECE-conform particulate measurement |
In addition, for certification testing, legislation defines certain measurement principles that must be used, such as Constant Volume Sampling.
The AVL SolutionThe highlight of AVL's solution for heavy-duty engine emissions testing is the emissions automation package GEM 301H, combined with PUMA Open – a proven solution that ensures a high level of test bed productivity by incorporating time-saving features specific to heavy duty emissions testing, such as
| online quality checks and report generation according to EPA standards | | pre-defined ECE test runs and regression analyses | | User-oriented GUI, which guides the operator according to the legislative test procedure or can be adapted for R&D applications |
With these features included, training is kept to a minimum and the test bed can be used productively immediately after commissioning.
For transient applications AVL offers the ideal dyno and control solution with the DynoExact APA in combination with the EMCON 400 Monitoring and control system, allowing exact control of the dyno and unit under test.
AVL's test solution is unique in that the automation is a homogeneous system, ensuring all data is acquired in synchrony and can be accessed/visualised via a central user interface. This saves a great deal of time – the data does not need to be synchronised in post-processing, less wiring is needed in the cell and a higher test quality can be achieved, in particular for transient tests.
AVL's complete range of emissions test systems means that solutions are provided not only for gaseous emissions – these are configured depending on the application. AVL is also the market leader in particulate measurement equipment, providing solutions for measuring particles and opacity that conform with ECE and US non-road regulations.
Emissions Analysis Equipment
| Steady-state certification |
The engine is operated at constant load and speed conditions (modes). The normal pattern of the engine operation is represented by weighting factors for each engine condition. All emission measurement is done by samples from the raw exhaust. As an option also systems for transient testing can be used.
| Transient Certification |
The engine is operated at transient load and speed conditions, which represents the normal pattern of the engine operation.
For certification tests the exhaust must be diluted with air by a CVS (constant volume sampling) system. HC, NOx and Particulate emissions are sampled continuously from the dilution tunnel. CO2, CO and all back ground concentrations are usually determined from the sample bags.
| Transient Engine Development Testing |
In principle the same equipment as for certification is used. In addition raw gas emission measurement is required in order to supply the development engineer with the required online time resolved result (Modal analysis). For modern engine concepts an EGR (exhaust gas recirculation) measurement option will be helpful. For engines with advanced exhaust aftertreatment systems (Euro V, US 2007) also not limited emission components might be required, like NH3, N2O,.... and a pre- and post cat raw gas measurement stream.
| AVL CEB II Combustion emission bench (Pre-Cat, Post-Cat, EGR) | | AVL CVS 4000 Constant Volume Sampling system | | AVL SPC Partial flow dilution particulate sampler (R&D) | | AVL Opacimeter 439 | | AVL 415S Smoke Meter |
Mechanical ComponentsAVL offers a wide range of mechanical equipment for test bed operation. Proven standard solutions cover many automotive applications. In addition AVL provides tailor-made systems.
Standard mechanical components for an engine test bed are:
| AVL Cable Boom and Boom Box FEM or Wallbox FEM | | AVL Drive Shaft System | | AVL Engine Mounting System | | AVL Intermediate Bearing | | AVL Intermediate Frame | | AVL Isolated Base Plate | | AVL Pallet System | | AVL Shaft Guard |
Dynamometer | For steady-state testing of heavy-duty engines AVL offers a range of hydraulic dynamometers, the AVL Omega Series. | | For transient testing AVL offers the AVL DynoExact APA Series of dynamometer and the AVL DynoRoad AFA Series. |
Data Acquisition, Automation and ControlFor heavy duty emissions testing AVL offers a flexible automation package, AVL PUMA Open Heavy duty testing. This package includes the functionality from AVL GEM, providing emissions-specific functionality.
For dynamometer and engine control required for transient emissions applications AVL offers the EMCON 400 system, integrated within the automation system PUMA Open.
The proven AVL Front End Modules (FEMs) have been developed for data acquisition because they can be positioned in the cell, close to the unit under test, maximising signal quality.
Product Description
AVL GEM Emission Automation Software
Actuators and SensorsThe following sensors can be provided as required:
| Ignition timing systems | | Temperature Sensors | | Air Mass Flow Meters | | Humidity measurement systems |
AVL offers a range of actuators for use on engine, transmission and powertrain test beds. Together with the automation System PUMA Open they allow fully automated test runs and simulations of driving conditions.
| AVL Throttle Actuator FVG 9400 – Adjustment of the throttle valve or injection pump | | AVL Throttle Actuator FVG 9400 EC – Adjustment of the throttle valve or injection pump for legal driving cycles | | AVL Throttle Actuator THA 100 - Adjustment of the throttle valve or injection pump for legal driving cycles |
Media Conditioning EquipmentAVL provides media conditioning equipment for the units under test and the media – coolant, oil, combustion air, fuel.
| AVL 553 Coolant Conditioning System | | AVL 554 Oil Conditioning System | | AVL Combustion Air Conditioning System | | AVL Dynamic Combustion Air Conditioning System | | AVL Fuel Temperature Control | | AVL Boost Air Conditioner | | AVL Exhaust Back Pressure Adjustment Kit |
Operating Panels and CabinetsDepending on the available space and the test equipment required, AVL offers a range of easily adaptable modular system cabinets and operating consoles. Where only limited space is available, special compact solutions are available.
| AVL Test Commander Operating and Control Desk | | AVL Test System Operating and Control Cabinet | | AVL Test System Operating and Control Desk | | AVL Compact Cabinet – wall mounted 19" cabinet | | AVL Console for the operating panel AVL P400 | | AVL Wallbox FEM |
Other InstrumentsServiceTo round off the AVL solution we offer a range of services to ensure reliability and availability of your AVL test cell.
| AVL eSpares online spare part procurement ensures rapid ordering and delivery of standard spare parts | | Hotline for fast and personal response to your queries | | Training, to ensure that you make the most of your AVL system | | Software Care Packages | | Full repair service |
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