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Online Library

    KULI Online library
  • Calculation of Operating distance for electric vehicles
    03.07.2014
  • KULI-System

    The Subsystem can be used for the calculation of the operating distance of a vehicle. Basically it can directly be used for electric vehicles, but with slight modification also for conventional combustion engines.
    The calculation is done in every time step. Due to the fact that the Operating distance is based on averaged values, the accuracy of the result increases with the amount of simulation steps.

    Necessary input values are:

    • Current SOC (State of ChargeI
    • Initial SOC
    • Minimal SOC
    • Velocity of the vehicle

    Output:

    • Expected remaining range
    • Expected total range of vehicle
    • Driven distance (up to now)
    Usable from release: KULI 9.1-0.01
    Necessary modules: KULI base + KULI drive


    KULI File, 15 KB
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  • A Simple Transmission Cooling System
    10.06.2014
  • KULI-System

    The gearbox delivers a significant amount of heat to the gearbox oil, depending on the efficiency of the gearbox in the current operating conditions. This model demonstrates how the amount of heat can be calculated and put into the appropriate locations in the circuits.

    The central element is an efficiency map, based on gear, torque, rpm, and temperature. The conversion from mean eff. pressure to torque is included with the help of calculation controllers. The heat of the gearbox is put into a point mass in an oil circuit. The point mass is also connected to another point mass via a heat conduction component with which it is possible to consider the heat transfer to the ambient.

    Usable from release: KULI 8.0-1.04
    Necessary modules: KULI base + KULI drive


    KULI File, 19 KB
    Documentation, 151 KB
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  • Automatic Creation of Radiator Files from Excel
    10.06.2014
  • KULI-System

    The COM interface, developed by Microsoft®, provides a standardized interface for programs to communicate with each other. KULI components has a set of built-in COM commands, which allows external programs to create KULI component files.

    The part of KULI components that allows to save component files is implemented as a dynamic link library (DLL). This KuliCompInterface.dll can be called by any other application that supports COM. The current example is a simple demonstration of the KULI compinterface. An Excel datasheet for KULI input of a radiator component has an integrated button that allows to store the data directly as an *.kulirad-file.

    Usable from release: KULI 8.0-1.04
    Necessary modules: KULI CompInterface + KULI MediaX


    KULI File, 131 KB
    Documentation, 427 KB
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  • Engine Modeled with Point Masses
    10.06.2014
  • KULI-System

    Only transient simulation allows using the full potential of computer aided engineering regarding component sizing & packaging.
    For the simulation of realistic temperature profiles the thermal capacities of the engine should be considered.

    In this example the existing engine component from KULI drive is remodeled using the primitive components point mass and heat conduction. The engine can be modeled as two direct masses and two indirect masses.The direct masses are heated by combustion processes, and exchange heat with each other, the oil and the water circuit respectively, the ambient air and with the indirect masses. The indirect masses exchange heat via conduction with their respective direct mass only.

    Usable from release: KULI 8.0-1.04
    Necessary modules: KULI base + KULI drive


    KULI File, 17 KB
    Documentation, 146 KB
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  • Example of a Hybrid Passenger Car
    10.06.2014
  • KULI-System

    In this example we will investigate, how to model a hybrid passenger car with KULI. We will especially focus on the electric components and their integration into the overall cooling system.

    Focus on

    • Battery model (module level)
    • Module temperatures
    • Coolant temperatures
    • State of charge Simulation
    • Electric motor and power electronics
    • Cooling system integration
    Usable from release: KULI 8.0-1.04
    Necessary modules: KULI base + KULI drive


    KULI File, 111 KB
    Documentation, 3 MB
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  • Modelling a Fan Control
    10.06.2014
  • KULI-System

    The aim of a decent fan control strategy is to provide adequate air flow for the cooling system at minimum fan power and noise.

    The KULI controller objects enable to implement an arbitrary  control strategy for system optimization. 

    In the subsystem Fan control the controlling information is set up. For comfortable use you can change the values for the temperatures for changing the fan stage and the fan stages itself in the inner circuit window. 

    Based on the fan (electrical or mechanical fan) the fan stage or the fan speed can be used as the controlled parameter. In the provided model an electrical fan switches on as the air temperature rises above 60°C and switches off as the temperature falls below 55°C. The transient aspect of the example is the hysteresis which can be modeled using a delay controller. For better system overview the control strategy is packed into a KULI subsystem.

    Usable from release: KULI 9.1-0.01
    Necessary modules: KULI base


    KULI File, 160 KB
    Documentation, 174 KB
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  • Thermostat Modelling
    10.06.2014
  • KULI-System

    In the coolant circuit the thermostatic valve is one of the most important control units to maintain the system’s desired set point temperature. Due to its mechanical technology usually the thermostat has some delay in its reaction, which should be considered in transient cycle simulation. This example is based on the tutorial example ExEngine. The major modification is that it includes a more detailed model for the thermostat, placed in the subsystem “Thermostat”.

    The main idea is that a fluid point mass models the wax element including the metal housing of the thermostat. This point mass is responsible for the hysteresis of the thermostat. The mass of the point mass can be adjusted to fit the current application; moreover, also the heat transfer coefficient from the coolant to the mass can be adjusted, even depending on the flow rate. A corresponding characteristic line is prepared (but contains only a single value in this demo example). 

    The temperature of the mass (i.e., of the wax element) is then taken into a characteristic line in which the lift opening (between 0 and 100%) of the thermostat is calculated. Based on this lift opening two fluid resistances are calculated that have opposite behavior: If the temperature is still low, then the resistance of the bypass will be low, the resistance of the exit to the radiator branch will be high. If the temperature is high, then it is vice versa. 

    The example is given for a thermostat working as a branch; the method would work in the same way for a thermostat working as a confluence.

    Usable from release: KULI 8.0-1.04
    Necessary modules: KULI base + KULI drive


    KULI File, 24 KB
    Documentation, 224 KB
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  • Viscous Clutch
    09.06.2014
  • KULI-System

    This subsystem models a viscous clutch via a point mass.

    The warming up hystereses are defined via the following inputs:

    • Mass of the point mass (represents the housing + the fluid inside the viscous clutch)
    • Heat transfer coefficient: defined over a characteristic curve dependent on the air mass flow (the higher this value is, the lower is the difference between engaging- and disengaging temperature)
    • Engagement Ratio: defined over a 3D-map dependent on engine revolutions and the temperature of the point mass (the median of the hysteresis in the disengaged case is defined via the temperature of mass for 0% engagement and the median of the hysteresis in the engaged case is defined via the temperature of mass for 100% engagement, thus the slope of the hysteresis is defined as well, see the green curves in the picture below)

    Furthermore the transmission ratio from engine speed to the input speed of the viscous clutch is modeled via a constant factor. And the transmission from the clutch-input speed to the fan speed is modeled via a 3D-map (“fan_rpm”) dependent on the engagement Ratio.

    Usable from release: KULI 9.1-0.01
    Necessary modules: KULI base + KULI drive


    KULI File, 10 KB
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  • Modelling Tanks
    23.05.2014
  • KULI-System

    Charge air cooler tanks may have a big impact on the efficiency of the heat exchangers behind. A simple approach to model those effects in KULI is the use of area resistances to block the air flow in the area where the tanks of the charge air cooler are located.

    The area resistances correspond to the size of the real -life tanks.To consider the high air resistance typically caused by the tanks a high pressure loss coefficient has to be set. To model the local impact regarding the heat exchanger surfaces the area resistances simply can be integrated to the cooling package using the KULI block function.

    Usable from release: KULI 8.0-1.04
    Necessary modules: KULI base


    KULI File, 99 KB
    Documentation, 209 KB
    Please login for Download.
  • Adding a Heater Matrix to a Cooling System
    23.05.2014
  • KULI-System

    The heater matrix uses coolant to warm the air that enters the passenger cabin. Of course, this can influence the behavior of the complete coolant water circuit. This example illustrates how to add a heater matrix to a System. 

    To take care of an additional heater matrix in an existing KULI cooling system one has to add a radiator component to the KULI system. On the fluid side it is integrated to a normal coolant circuit using branch and confluence components. On the air side it is necessary to use two parallel branches to simulate separate air paths for the engine cooling part and for the HVAC part. The example is based on the basic example “Ex_Fluid.scs” from the KULI installation setup.

    Usable from release: KULI 8.0-1.04
    Necessary modules: KULI base


    Lectures, 197 KB
    Documentation, 189 KB
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