Week-4 Challenge WOT Condition Part-2
STUDENT FROM BATCH 16 ONLINE CLASS
1.What is the difference between mapped and dynamic model of engine, motor and generator? How can you change model type?
Mapped model
It is a model that is used when pre defined values are required for simulation. And it will be entered in the form of Lookup tables.
When there is detailed information available with us then the simulation will become easy.
Engine: Simulation of engine datas could be done from the array of datas in the system. Other parameters like engine torque etc can be determined accordingly.
Motor: Specifications of the motor like rpm, efficiency etc have to be enterd before simulation.
Generator: The internal specifications like current, voltage etc have to be given for simulation.
Thus mapped model simulates based on the array of datas that are already provided.
Mapped motor model
Mapped model parameters
In this block, parameters are given before simulation.
Dynamic Model
In this model, we have to give each parameters in each blocks instead of pre assigned values.
It provides us with detailed analysis of the variations that we have given.
It operates dynamically depending on the situation of the operation.
There will be vehicle feedbacks for comparing the output with the input.
Engine: The engine simulation will be done by taking the real time datas of the vehicle at the simulation time.
Motor:The actual details of the motor are taken into consideration.
Generator: Here also similar to above real time datas are taken into consideration for simulation.
Thus unlike mapped models the dynamic models take real time datas for simulation instead of pre designed array of values.
b) The model type of mapped engine can be changed as per the block diagram below.
By right click the engine subsystem. The click on the variant option and in that click on the label mode active choice. By clicking on it the engine variant can be changes to SIEngine, SiMappedEngine adn Simple Engine.
Similar proces can be done for electric motor and generator.
2.How does the model calculate miles per gallon? Which factors are considered to model fuel flow?
For calculating miles per gallon or the fuel efficiency, the model uses following parameters
1) Vehicle speed
2) Fuel volume flow
3) Battery power
Vehicel speed is used for calculating the distance travelled. For this the speed is converted to distance by integrator block. It is in miles/hr
Fuel volume flow is expressed in kg/sec. It is converted to mass of the fuel by integrating. By multiplying it with 1000 it is converted to Litres.
Battery power: Here the amount of power of battery is given in watt. It is convertd into kW by dividing by 1000.Then it is converted into energy. After that energy is converted into US gallon by dividing it with 33.7.Now inorder to find the gallons per sec then it is divided by 3600.After multiplying with 0.00378541 it is converted to volume.
These factors along with the US environmental codes the fuel efficiency is calculated.
Factors considered for model fuel flow
Fuel flow is here is expressed in kg/sec. It is then integrated by using integrator block and converted to volume. Later it is multiplied by 1000 in order to convert to litre. Also the volume of fuel is multiplied by 264.172 to convert it into US gallon.
