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Stable release | 5.6.0 / December 2016 |
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Preview release | 5.4.19 / October 2015 |
Operating system | Microsoft Windows |
Website | www |
EcosimPro is a simulation tool developed by Empresarios Agrupados A.I.E for modelling simple and complex physical processes that can be expressed in terms of Differential algebraic equations or Ordinary differential equations and Discrete event simulation.
The application runs on the various Microsoft Windows platforms and uses its own graphic environment for model design.
The modelling of physical components is based on the EcosimPro language (EL) which is very similar to other conventional Object-oriented programming [1] languages but is powerful enough to model continuous and discrete processes.
This tool employs a set of libraries containing various types of components (mechanical, electrical, pneumatic, hydraulic, etc.) that can be reused to model any type of system.
It is used within ESA for propulsion systems analysis [2] and is the recommended ESA analysis tool for ECLS systems. [3] [4]
The EcosimPro Tool Project began in 1989 with funds from the European Space Agency (ESA) and with the goal of simulating environmental control and life support systems for crewed spacecraft, [4] such as the Hermes shuttle. The multidisciplinary nature of this modelling tool led to its use in many other disciplines, including fluid mechanics, chemical processing, control, energy, propulsion and flight dynamics. These complex applications have demonstrated that EcosimPro is very robust and ready for use in many other fields.
Differential equation
To familiarize yourself with the use of EcosimPro, first create a simple component to solve a differential equation. Although EcosimPro is designed to simulate complex systems, it can also be used independently of a physical system as if it were a pure equation solver. The example in this section illustrates this type of use. It solves the following differential equation to introduce a delay to variable x:
which is equivalent to
where x and y have a time dependence that will be defined in the experiment. Tau is datum provided given by the user; we will use a value of 0.6 seconds. This equation introduces a delay in the x variable with respect to y with value tau. To simulate this equation we will create an EcosimPro component with the equation in it.
The component to be simulated in EL is like thus:
COMPONENT equation_test DATA REAL tau = 0.6 "delay time (seconds)" DECLS REAL x, y CONTINUOUS y' = (x - y) / tau END COMPONENT
Pendulum
One example of applied calculus could be the movement of a perfect pendulum (no friction taken into account). We would have the following data: the force of gravity ‘g’; the length of the pendulum ‘L’; and the pendulum's mass ‘M’. As variables to be calculated we would have: the Cartesian position at each moment in time of the pendulum ‘x’ and ‘y’ and the tension on the wire of the pendulum ‘T’. The equations that define the model would be:
- Projecting the length of the cable on the Cartesian axes and applying Pythagoras’ theorem we get:
By decomposing force in Cartesians we get
and
To obtain the differential equations we can convert:
and
(note: is the first derivative of the position and equals the speed. is the second derivative of the position and equals the acceleration)
This example can be found in the DEFAULT_LIB library as “pendulum.el”:
COMPONENT pendulum "Pendulum example" DATA REAL g = 9.806 "Gravity (m/s^2)" REAL L = 1. "Pendulum longitude (m)" REAL M = 1. "Pendulum mass (kg)" DECLS REAL x "Pendulum X position (m)" REAL y "Pendulum Y position (m)" REAL T "Pendulum wire tension force (N)" CONTINUOUS x**2 + y**2 = L**2 M * x'' = - T * (x / L) M * y'' = - T * (y / L) - M * g END COMPONENT
The last two equations respectively express the accelerations, x’’ and y’’, on the X and Y axes
EcosimPro has been used in many fields and disciplines. The following paragraphs show several applications
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Numerical methods for ordinary differential equations are methods used to find numerical approximations to the solutions of ordinary differential equations (ODEs). Their use is also known as "numerical integration", although this term can also refer to the computation of integrals.
In mathematics, a linear differential equation is a differential equation that is defined by a linear polynomial in the unknown function and its derivatives, that is an equation of the form
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In mathematics, a differential equation is an equation that relates one or more unknown functions and their derivatives. In applications, the functions generally represent physical quantities, the derivatives represent their rates of change, and the differential equation defines a relationship between the two. Such relations are common; therefore, differential equations play a prominent role in many disciplines including engineering, physics, economics, and biology.
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In mathematics, delay differential equations (DDEs) are a type of differential equation in which the derivative of the unknown function at a certain time is given in terms of the values of the function at previous times. DDEs are also called time-delay systems, systems with aftereffect or dead-time, hereditary systems, equations with deviating argument, or differential-difference equations. They belong to the class of systems with the functional state, i.e. partial differential equations (PDEs) which are infinite dimensional, as opposed to ordinary differential equations (ODEs) having a finite dimensional state vector. Four points may give a possible explanation of the popularity of DDEs:
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