Development and validation
Mechanical development of an engine is necessary to ensure that the engine will meet its deisgn targets, whilst the validation process provides a demonstration of the targets achieved.Our Approach
MAHLE Powertrain offers a complete service for the mechanical development of an engine including:
- In-depth investigation into problems which have been identified, leading to recommendations for problem resolution and verification of those recommendations
- The design of complete engine development programmes, from the building of first prototype engines to the conclusion of validation tests
- determination of the number and quantity of tests necessary to demonstrate a target level of reliability
Our Tools, Facilities and Services
A large library of test schedules, along with experience of their use in development programmes, are used in conjunction with design critiques and Failure Mode Effects Analysis (FMEA) to construct an efficient test matrix, whether at an individual problem, or an entire development project.
Engine dynamometers and rig tests are used, along with vehicle tests where appropriate.
Results of certain function tests may be used to correlate simulation models, such that efficient recommendations may then be generated to improve the air flow, oil flow or coolant systems for example. Specialist instrumentation is available to provide accurate assessments of engine parameters, whilst this can also be augmented by project-specific instrumentation requirements.
Durability and validation tests may be carried out using engines assembled to nominal (or special) design limits and with a high degree of components measurement before testing. Detailed examination of the same engine after durability testing allows an assessment of wear levels to be determined. Measurements of blowby, oil consumption, emission outputs, performance and elemental oil analysis allow the engine health to be determined during the progress of tests.
Customer Benefits
Testing can be precisely targeted against already-know failure conditions to better understand the cause of such a failure.
Test plans can be generated early in the design phase of a new engine, using the extensive engineering experience, design reviews and Failure Mode Effects Analysis (FMEA) as inputs to the process.
Project Examples
Friction assessments
Customer engines undergo a friction 'teardown' procedure, that allows the friction levels in the engine to be apportioned to the various engine systems. These results have then been compared against a benchmark data set. This allows design recommendations for the reduction in friction to be efficiently targeted at engine systems that perhaps show higher levels of friction than the norm.
Custom Rig Tests
The use of rolling element bearings is becoming more common but it was necessary to demonstrate that such bearings would not fail due to reasonable variations in oil quality, oil temperature, oil quality or assembly processes. A customised rig was designed and built to allow bearings to be tested with these various parameters altered in a controlled fashion.
Function Tests
A novel engine concept is tested for the first time and initial data collected to allow the lubrication system, friction, performance, cooling and other systems to be assessed against predicted performance levels. A comprehensive list of instrumentation is specified. In common with all prototype engines, it is necessary to gradually explore the operating envelope in a safe manner and confirm satisfactory operation, before exposing the engine to the risks associated with prolonged operation at high loads, high speeds or combustion knock for example.
Tilt Tests
The oil handling capability of an engine is determined using an engine mounted to a frame that can be tilted simultaneously in two axes. The level of tilt simulates the effect of dynamic cornering forces, braking and acceleration. The levels of tilt that the engine can accommodate is given by the limit at which satisfactory levels of oil aeration, oil carryover and oil pressure can be achieved.
