DYNATUNE-XL LONGITUDINAL DYNAMICS
DYNATUNE-XL does offers also "Longitudinal Dynamics Tools". Two highly efficient tools have been developed for those people that need to modify their gear ratio's and get the best acceleration package with their available engine or want to improve/design the braking system and verify it's performance. The tools have recently been added to the product portfolio and are focused - as all DYNATUNE-XL Tools - to deliver a maximum of information with a minimum of required input data.
Both tools are based on MS EXCEL ® workbooks and do only use standard workbook functions for all calculations (without any additional VBA code) and are therefore fully compatible with all Version of MS EXCEL ® from 2007 onward.
Both tools are based on MS EXCEL ® workbooks and do only use standard workbook functions for all calculations (without any additional VBA code) and are therefore fully compatible with all Version of MS EXCEL ® from 2007 onward.
DYNATUNE-XL BRAKE-SYSTEM DESIGN MODULE (BDM)
In the Brake System Module the most important data to be supplied are Brake Disc Dimensions, Caliper Piston Diameters and Master Cylinder / Brake Pedal Data . The tool allows to investigate two vehicles in two load conditions and compare their key performance characteristics. The Tool is designed for Caliper/Disc Systems, does NOT consider any Brake Boost Devices and is governed by a Brake Balance Bias Bar which defines the Brake Distribution between the Front and Rear Axle.
BRAKE-SYSTEM input data
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As to be expected, the main Brake System Data to be supplied are those of the Brake Calipers and Discs. The Calculation Algorithm is based on the principle of a 1 Piston Floating Caliper (piston located at the inside of the disc) and all data of Fixed (multi-piston) Calipers will be internally converted to that principle. Up to 3 different sizes of pistons can be used allowing maximum flexibility in geometric design.
Next to the data for Front & Rear Wheel Brakes, the Master Cylinders Dimensions have to be provided and some basic geometry data of the Brake Balance Bias Bar & Brake Pedal Dimensions. 
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And some Specific Data to consider the effects of Piston Friction and Brake Pad Deformation.
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In RELEASE 8.0 the user may select between a Standard OEM Tandem Brake Master Cylinder or the already available Brake Balance Bias Bar which is used in Racing Applications. All internal Calculations will be executed based on the Selection. This additional feature does make DYNATUNE BDM now fully applicable to most of all OEM Vehicle Hydraulic Brake System Layouts.
VEHICLE Data
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The most important vehicle data are of course Vehicle Mass, Weight Distribution, Center of Gravity Height and Wheelbase since these parameters define the longitudinal load transfer and wheel loads under Braking. Additionally the tool can consider two load conditions of the vehicle.
The Axle Loads are generated for the Imposed Vehicle Speed. It should be mentioned that the tool in RELEASE 8.0 is fully capable of simulating high down force vehicles and does especially consider the effect of High Drag Coefficients on overall Braking Performance. |
RESULTS
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NUMERICAL RESULTS show the most interesting metrics of the Braking System for 2 Load Conditions. Key Brake Operating Characteristics are Brake Line Pressure (& Ratio Front to Rear) and Brake Pedal Force % Travel. Based on the provided Vehicle & Tire Data the tool calculates automatically the Grip Saturation at each Axle for the given Brake Balance Distribution
In RELEASE 8.0 both Hydraulic & Aerodynamic Braking Performance are being presented in the Results Table. Beyond that all interesting details of the Braking System are available as intermediate results. A Brake Pressure Control Valve can limit the maximum Brake Line Pressure if needed. 
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And also all important details of the Brake Pedal for the Selected Master Cylinder Configuration.
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And the final Vehicle Result: Stopping Distance
GRAPHICAL RESULTS consist out of 3 Graphs from which the classical Axle Grip Saturation vs. Vehicle Deceleration Graph is the most important. The other Graphs show Brake System Actuation Forces and Displacements..All Graphs contain an indication of the Physical Limit of the Vehicle. Beyond that, some of the EU-Homologation requirements are considered in the first graph as a reference guide for street legal vehicles.
This workbook contains also a COMPARISON Sheet in which all key Parameters and Graphs for 2 Vehicles (and their 2 load conditions) are listed allowing an easy back to back comparison of variants. Have a look at the BDM PDF file to find out more about it.
