Founded in 1979 by the Society of Automotive Engineers (SAE) the Formula Student is an international engineering design competition for students. In only one year, students found a team, develop and build their race car to compete. This unique opportunity offers students to turn theoretical knowledge into a concrete practice. The growing popularity of the competition is proven by the fast rising number of teams and sponsors, such as Siemens PLM.
Today, the goal for Siemens PLM is to help students building more efficient, lightweight and reliable race cars from one year to the other. Modeling and simulate a race car cooling circuit using a system approach with LMS Imagine.Lab Amesim is a way to achieve their performance target.
This step by step demo is aimed at students who want to design a more efficient cooling system for their team race car.
Most teams consider the cooling circuit as an important part of the car but don’t really know about the real cooling demands of their race car. A simple cooling system in a race car consists of four components – heat sink, heart source, pump and catch can. Here, these parts are modeled in a way allowing an easy adaptation and change of the parameters.
The heat is generated either by the IC-Engine or the electrical drive. To model the heating behavior a thermal capacitance from the thermal library is used. With the material icon a typical material, e.g. iron, and its thermal properties can be associated. The thermal capacity is connected to heat flow input in Watt.
In LMS Imagine.Lab Amesim an ideal fixed displacement thermal-hydraulic pump from the thermal hydraulic library is used. Flow losses or mechanical losses are neglected. The pump is directly connected to a constant speed prime mover. Sensors before and after the pump are used to analyze the temperatures.
The catch can is represented by a model of thermal-hydraulic accumulator, which is composed of a liquid phase and a gas phase in pressure equilibrium. To connect the catch can to the rest of the system an orifice is used.
The heat sink represents the cooling component in the systemSimilar to the heat source, specific material and geometrical propertied, e.g. weight, can be associated. In order to take in account the geometry of the radiator, a thermo-hydraulic pipe with heat exchange is used. The geometrical characteristic of the radiators, e.g. diameter and length of the pipes are input data. Additionally, the coolant properties can be set using the fluid data component located in the sketch.
The pipes of the radiator are cooled using the ambient air. The users can either set directly the mass flow of the air or the velocity of the car. The calculation is done automatically within LMS Amesim. The air properties are defined using the pneumatic gas data icon placed in the sketch.
Creation of the cooling system:
To realize a complete cooling circuit, all the subsystems described above need to be connected together in order to get following system:
To find out the cooling demands of their racecar the teams only need the basic data given in the datasheets. To easily parametrize the model a user interface, called “App”, has been created using the Python capabilities of LMS Amesim. The teams can easily adjust the parameters to see how the cooling demands change e.g. when the temperature is higher or the diameter of the cooling hoses change.
The teams can simulate the different cooling demands for each race and make the cooling system more reliable by knowing how the different ambient temperatures effect their cooling.
Do you want to deploy LMS Imagine.Lab Amesim or other Siemens PLM Software tools in your team?
NB: the model will be provided to Siemens sponsored teams in order to encourage other teams to request such a sponsoring