Simulate Real World Conditions with a Towing Dynamometer

Towing Dynamometer Test Applications

The towing dynamometer is an excellent tool for simulating real world conditions in a measurable and repeatable manner. Test engineers are able to quickly and effectively compare various tunings, parts and thermal conditions while driving in real world conditions.

Most towing dynamometers offer three simple modes of operation:

• Closed Loop Speed: The dynamometer controls the speed according to the speed input from the controller and the operator controls the load with the accelerator.
• Closed Loop Load: The dynamometer controls the load according to the load input from the controller and the operator controls the speed with the accelerator.
• Manual Load: The operator simply increases or decreases the load from the controller.

Advanced Hill Simulation

Some towing dynamometers have advanced features such as hill simulation (this is standard on Taylor’s DynCntrl II system. This allows the test engineer to create a hill profile and/or the ability to input pre-surveyed hill profile data into a test format.  From this profile, the test engineer is able to simulate the hill profile while going around a flat test track. For example, it is possible to make a vehicle react as if it is actually climbing Vail Pass in Colorado while going around a flat desert track in Dubai.

The hill simulation test is often used for thermal tests; transmission shift tests and fuel economy tests. It is extremely useful for simulating long mountain passes without being concerned about traffic or long distance travels to and from the mountain passes. Furthermore, it allows the test engineer to quickly conduct mountain pass tests when the weather conditions are ideal for testing.

Other more advanced hybrid towing dynamometer models also have the ability to push and therefore can simulate a negative or downward slope.

Variable Trailer Size/Weight Simulation

Another advanced feature is the ability to simulate larger, heavier trailers. Various trailer size simulation allows the test operator the ability to input the desired trailer weight and frontal area (or wind tunnel aero numbers) of a given trailer. Within the limitations of the towing dynamometer, it will then load according to the desired trailer data and thus simulate a trailer different than that of itself. Therefore, a test operator can quickly test the vehicle’s reaction to different trailer sizes and weights without the need for connecting and disconnecting multiple trailers.

Various Vehicle Weight Simulations

Pickup trucks and SUV’s commonly get filled with cargo and/or people, which weigh the vehicles down and thus change their performance characteristics. Another advanced feature of the towing dynamometer is the ability to simulate added vehicle weight. It is important to note that this does not change the actual weight of the vehicle but instead adds a pulling force to the vehicle thus simulating the performance needed to haul the desired load of cargo.

Real World Application

Towing Dynamometer customers are constantly discovering the great advantages that the towing dynamometer offers. The towing dynamometer, allows the test engineer to test in real world conditions with real wind speed, road friction, vehicle frictional and aero losses.

The following are some excellent ways in which towing dynamometers can be used:

Thermal Testing

• Compare various cooling parts (i.e. pumps, radiators, intakes, etc.) under measured loads or throughout a hill profile
• Program cooling system flow and fan triggers at measurable and repeatable thermal steps
• Compare various lubricants and coolants at measurable and repeatable thermal steps using constant or variable dyno loads
• Mechanical parts (such as bearings) temperature testing under various load conditions

Drive Train Testing

• Transmission performance and shift reactions under various load conditions
• Mechanical noise and vibration tests under various loads
• Comparing various gear selections in relation to power performance
• Calibrating and or measuring NOx sensors

Cruise Control Testing

• Programming cruise control and evaluating cruise control reactions under various load conditions

Fuel Economy and Emissions Testing

• Using a repeatable steady state load to measure and evaluate fuel consumption after making quick engine program, engine component, gearing and aero panel changes
• Ability to evaluate fuel economy in different weather conditions with the same hill profile
• Measuring emissions and emissions component changes under various measurable loads

There are many applications in which the towing dynamometer can be used. In general, it is an excellent and efficient tool, which saves money, eliminates un-needed travel and prototype exposure and gives reliable, repeatable data. Towing Dynamometers are very simple to use and easy to apply to a multitude of test applications. Contact Taylor for more information about Towing Dynamometers email: sales@taylordyno.com or call (414) 755-0040.