The engine simulators calculate the thermodynamic and gasdynamic of internal combustion engines. Such software have as input data all the geometry of the engines and give as output power, consumptrion, volumetric efficiency ecc.. The following software are released:
Forte4T V1.1: 4 Stroke Engines Simulator;
4TMono V1.0: Highly professional 4 Stroke Engines Simulator;
DiSim V1.0: Diesel engine Simulator.
The following softwares are in development phase:
VDin: Software for the OnRoad Dynamic behaviour of vehicles;
DCam: CamShaft Designer.
Forte4T
Forte4T is a 4 stroke spark ignition simulation software; it can estimate the performance of the abovementioned engines and is therefore an excellent tool in phase of design or tuning.
The usage of the software is very simple and allows the display of many motoristic variables of interest. There are more than 60 graphs for each simulation, so every part of the engine can be observed adequately: the advantages of Forte4T are therefore to be able to study and optimize the 4 stroke engines and to have many information that in experimental way are not simple to obtain.
Such results can be showed in graphs form, but can be printed like ‘Files’, then easily exported easily manipolable and printable.
The technical features of Forte4T are:
 “Two zone” combustion model: during the combustion phase, the gas is divided in two parts: the mixture and the combustion products. Such combustion products are hypothesized to be in chemical equilibrium, while the mixture is assumed to be in a frozen composition. The combustion law used is the Wiebe equation;
 Annand model for the heat transfer between the gas (subdivided in “two zones”) that works in the cylinder and cylinder walls;
 Model for the calculation of the blowby (mass that flow away from the cylynder via the piston rings) during the phases of compression, combustion and expansion;
 Calculation of the chemical equilibrium of the products of the combustion: it take in consideration 10 chemical elements:

 Monodimensional model for the inlet and exhaust ducts: the model used is “Two Step LaxWendroff “ + TVD, in which it takes account of the variation of section, friction, heat transfer and the variation of the thermodynamic properties of the gas and of its composition;
 Monodimensional model for the boundary ducts: it is used the “CIR” method, and the solution is calculated every instant with non linear systems of equations;
 Threedimensional maps of the discharge coefficients for inlet and exhaust valves; such coefficients, how is known, depend both from the valve lifting, and from the pressures ratio upstream and downstream of it;
 Perfect mixing during the overlap period of the valves (scavenging);
 Model for the calculation of knock.
In this version is possible to simulate the following typologies of engines:
 Monocylinder engines or engines with the cylinders fluidodinamically independent, i.e. there aren’t pipe junctions or connections between ducts of different cylinders;
 Engines with 2 or more valves for cylinder;
 Variable advance with the RPM;
 Vaiable airfuel ratio with the RPM;
 Variable inlet valve opening with the RPM;
 Variable exhaust valve opening with the RPM;
 Inlet box: assimilable to the “AIR BOX” or to the box in which is situated the air filter;
 Exhaust box;
 Partial loads;
 8 different typologies of fuel:
 Octane
 Leaded Gasoline
 Unleaded Gasoline
 Methane
 Propane
 Methanol
 Ethanol
 Hydrogen
Go to the Downloads section to download the Demo Version or the use manual
For further informations contact RTZ Soft : [email protected]
4TMono
4TMono is an evolution of Forte 4T with the following emprovements:
 Turbulent combustion model, taking account of the combustion chamber geometry (BlizardKeck model) with a turbulence model over the thermodinamic cycle;
 Emproved cylinder heat transfer model;
 Added further valve lift model (polinomial);
 Airbox (Ambient air not stagnant);
 Better model for the calculation for the thermodinamic properties of mixture and combustion products (13 combustion products);
 Better model for mechanical efficiency.
Below there are some results obtained with this software:
Example 1:
YZ400 engine presented in the SAE paper 2001011797/4218:
Example 2:
Monocylinder engine “G50” presented in the book “Design and Simulation of Four Stroke Engines” by Gordon P. Blair
Click here to go to the Download section to download the manual and the scientifical documentation
For further informations contact RTZ Soft : [email protected]
DiSim
DiSim V1.0 is a Diesel simulation software; it’s able to calculate the performances of such engines and it is therefore an excellent tool both in phase of planning and tuning. The use of the program is very simple and allows the display of many motoristic variables of internal combustion engines: more than 60 graphs for every simulation are available and every part of the engine can be observed adequately. The advantages of DiSim V1.0 are then, the possibility to study and optimize “Diesel engines” with the possibility to get information that can’t be easily obtained in experimental way.
Such results can be printed like ‘Files’ so they can be used as input data for other programs and also in text format ‘.txt’ ,easily printable.
The technical features of DiSim V1.0 are:
 “Watson” combustion model; after the ignition delay period (calculated by the simluator), the combustion is divided in two parts: the first is the premixed combustion and the second is the diffusive one;
 “Annand” model for the thermal exchange between the gas that works in the cylinder and his walls; also subdivided in “two zones”;
 Model for the calculation of the mass lost of mass across the piston rings during compression, combustion and expansion;
 Monodimensional model for inlet and exhaust ducts: the model used is “Two Step LaxWendroff “ + TVD, in which it takes account of the variation of section, friction losses, thermal exchange, variation of the thermodynamic properties of the gas and of its composition;
 Monodimensional model for the boundaries of the ducts; the method used is the “CIR”, and the solution is calculated every instant in non linear systems of equations;
 Threedimensional maps for the discharge coefficients of inlet and exhaust valves; such coefficients, how is known, depend both from the valve lifting, and from the pressures ratio upstream and downstream of it;
 Perfect mixing during the overlap period of the valves (scavenging);
In this version is possible to simulate the following typologies of engines:
 Monocylinder engines or engines with the cylinders fluidodinamically independent, i.e. there aren’t pipe junctions or connections between ducts of different cylinders;
 Engines with 2 or more valves for each cylinder;
 Variable advance timing with Rpm;
 Variable airfuel ratio with Rpm;
 Variable inlet valve timing with Rpm;
 Variable exhaust valve timing with Rpm;
 Inlet box: assimilable to the “AIR BOX” or to the box in which there is the air filter;
 Exhaust Box;
 Partial load.
Go to Downloads section to download the Demo version and the user manual
For further informations contact RTZ Soft : [email protected]
Coming Soon
VDin
RtzSoft VDin is a software for the simulation of the road dynamic behaviour of vehicles, motorcycles and Karts.
Knowing the values of the engine power and vehicle data, it gives:
 The power,torque, traction force graphs in function of the vehicle velocity for each gear ratio: it’s possible also to obtain the maximum possible velocity and the relative engine Rpm;
 Compatibility with all RtzSoft engine simulators so it’s possible to load the power curve from those softwares;
 Friction losses for tyres resistence, aerodinamic resistences, gear losses and road slope: in the software there are some correlations for the calculations of these losses(for example for the tyres resistence is sufficient specify the tyre type and its pressure);
 Drag tests and time needed to reach a certain velocity:it’s possible then to find the optimum gear ratios like the minimum, the maximum and all the intermediate ones;
 The maximum acceleration obtainable to avoid aderence limit and overturning (for motorcycles);
 Measurement of the engine power (for vehicles) with “DIAGNOSTIC OBDII CABLE” (see also the “Diagnostic” section) of the vehicle;it’s possible to have a dynamometer that measures the power in the real conditions.
DCam
DCam is a tool to design cams for four stroke engines. With it, knowing the geometric caracteristics of the system (mechanism type, valves distance,piston distance ecc.) and dynamics (contact pressure between cam and valve,spring force ecc.)
It’s possible to have a profile for the valve lift and for the cam.
The cam profile can be saved in a DXF file or in a ISO format to easily built with the CNC machine.
The supported camfollower mechanism types are:
 Direct acting (OHC);
 Push rod;
 Finger follower;
 Centre rocker.
The valve lift profiles developed are:
 Polydyne;
 Polinomial;
 Spline.