Manual mota

The DFCU screen lists the number of different types of port. It is always assumed that there is only one type of inlet port duct and one type of exhaust port duct. For each port type you are asked to enter the number of individual ports and say whether you will be providing profiled port data or not.

If you answer yes to the profiled data question you are asked for the number of ordinates you wish to use to describe the changing width of the port.

You can specify up to a maximum of 11 ordinates which corresponds to a maximum of 10 equispaced intervals. If you have two identical ports, you are asked whether they constitute a bridged pair as distinct from two separate ports. A bridged pair consists of two individual ports of identical geometries, separated by a relatively narrow "bridge" and being fed by, or feeding into a single duct. MOTA needs this information so that it can calculate the total effective port area accurately.

If you specify two or more unbridged ports, MOTA will assume that each port is fed by or feeds into a separate duct and that each of these ducts will be identical in geometry. For engines with separate exhaust booster ports the area of these ports needs to be included with that of the main exhaust port s.

In the case of a port which is not profiled, this can be approximated by increasing the effective arc width of the relevant main port so that the total area of that port includes that of the booster ports.

More accurately, the port may be considered as a profiled port so that the booster port areas can be included as part of the port profiling process see section 4. The exhaust port screen has a prompt for variable opening angle.

This is provided for engines with variable exhaust port timing, but you must know the relationship between the port opening angle and the engine speed. If you select this option, you are asked for the number of engine speeds at which the exhaust port opening angle will be specified. A "straight-line" relationship is assumed between adjacent points.

In the following sections, the data which needs to be entered on the piston controlled port screens is discussed. For each piston controlled port, the crankshaft angle at which the piston starts to open the port, the crankshaft angle at which the port is fully open and the port attitude angles are requested. If a port pair is defined as "bridged", the bridge width together with the top and bottom bridge radii must be provided for a rectangular port, but, for a profiled port, only the bridge width is required.

By definition a bridged pair shares a common duct and the projection of the bridge into this duct is relatively small. Figure 8a illustrates a section of a conventional rectangular bridged exhaust port.

OM represents a radius of the cylinder drawn to the mid-point M of the right hand port arc width. The radial attitude angle Ar is the angle made by OM and a line through M which is parallel to the port side wall close to the cylinder. An option provided on the Tools Menu can be used to calculate the value of the radial attitude angle of a bridged port pair. You will have to provide the values of the port arc width XY and the bridge arc width YZ.

An alternative construction is illustrated in Figure 8b. In this case the port wall close to the cylinder is parallel to the radius OM and experience suggests that a zero radial attitude angle should be used for such a port configuration.

For exhaust ports with variable opening timing, a table will be displayed for you to input the opening angle of the exhaust port at each of the engine speeds at which you have this information. This information is required when the port shape is rectangular with radiused corners see Figure 4. In addition to the values described above, the port arc width and the top and bottom corner radii must also be provided. Note that the value to be used for the port width is the arc width.

A facility to convert between chord width and arc width values is provided by clicking Tools on the Main MOTA Menu and then making the appropriate selection from the Tools Menu. Figure 8a Figure 8b. If you have chosen the profiled port option and have entered the number of ordinates in the profile data, you will need to fill in a table of ordinate port arc widths and the corresponding crankshaft angles.

Irregularly shaped ports should always be described by such a sequence of arc widths ordinates measured over a set of equispaced intervals spanning the full height of the port.

These ordinates should be submitted to the engine data file in the same order as that described by the port opening sequence. In the case of a profiled inlet port, particular care should be taken to submit the ordinates in the correct sequence of opening order, that is from the bottom of the cylinder upwards. A construction which divides one of the ports of an irregular shaped bridged port pair into six equispaced intervals, providing seven ordinates, is illustrated in Figure 5.

A pair of compasses, a pair of dividers, a rule, a set square and a fine pen or sharp pencil are minimum requirements for the performance of this work. Generally a suitable port outline can be obtained from a "rubbing" of the cylinder wall. Again note that ordinates representing arc width values should be provided. The construction illustrated in Figure 5 is completed as follows:. First draw parallel base and top lines at either extreme of the port height. Next, using a point O on the base line as centre, draw an arc which intersects the top line at point A.

The radius of this arc will exceed the port height and in particular, it should be easily divided into the required number of equal intervals , in this case six. Now mark the equispaced divisions of OA and finally draw the ordinates L1 to L5 as a sequence of lines parallel to the base and top lines.

The lengths L0 to L6 are best measured using a pair of dividers. Notice that the values of L0 and L6 have been adjusted in an attempt to provide realistic representations of the areas of the two extreme sections of the construction.

This screen is provided only if you selected the rotary valve inlet option on the Engine Configuration screen. Prompts on this screen ask you to enter the rotary valve data, a schematic of which is shown in Figure 9. You may have one duct or two identical ducts feeding one cylinder. The latter configuration is assumed to require two identical rotary valves.

Enter the number of rotary valves here. This is the crankshaft angle after top dead centre at which the port becomes completely closed. The port is assumed to be radially symmetric with respect to the crankshaft centre as in Figure 9. Any other geometry will have to be approximated within these bounds.

The radius to the bottom of the port is shown as Rv in Figure 9. This is the angle A in Figure 9. It is assumed that the port sides will lie along radial lines from the crankshaft centre, possibly with small radius corners. Any other geometry will have to be modified to fit this specification. This screen is provided only if you select the reed valve engine option on the Engine Configuration screen.

Prompts on this screen ask you to enter data for the reed valve. A typical reed valve is illustrated in Figure The latter configuration is assumed to require two identical reed valves.

Enter the number of reed valves here. Generally a reed block port is controlled by a single petal. However, in some cases two petals are clamped together with the length of the outer petal less than that of the inner petal. Such a configuration is referred to as a compound petal.

MOTA requires you to specify the type of petal, single or compound, contained in your reed valve. For compound petals, where one petal overlaps the other over part of the unclamped length, prompts appear for the combined thickness of both petals, and the unclamped length of the shorter petal.

Throughout this manual, "Duct" is the general term used to refer to any passage down which gas flows, for example, the carburettor, inlet manifold, exhaust pipe and the passages leading from the crankcase to the transfer port s. MOTA assumes that each duct comprises a sequence of linearly tapered sections.

Discontinuities in cross-section area at section junctions are allowed. Typically this may occur in an exhaust duct if the cross sections of the barrel section and the engine pipe are not perfectly matched at the barrel flange. Inlet and transfer ducts can also have more than one section.

The information required for all ducts is discussed in the following sections. The number of sections in each duct. The inlet duct must have a minimum of two sections even if each has the same cross-section area , the transfer duct and muffler duct must each have a minimum of one section and the expansion chamber duct must have a minimum of 4 sections. MOTA adds an extra section automatically for each of these last sections and prompts you for the relevant dimensions.

Notice that neither the part of the exhaust port duct which is contained in the cylinder barrel nor the tail pipe if one is present is considered to be an expansion chamber section for the purpose of data entry. The details of these duct sections are entered separately. Section numbering for each duct begins at the "inflow" end of the duct, that is, at the end of the duct into which fluid air, air fuel mix or the engine exhaust normally flows.

MOTA assumes that for the inlet duct, the first section starts immediately after any bellmouth present, so your first section measurements should not refer to any bellmouth. Once the number of duct sections is entered, a table is displayed with spaces set for the entry of the inlet diameter , the outlet diameter and the length of each section.

The table is scrollable if the duct comprises more than four sections. For some transfer ducts you may not be asked to enter the outlet diameter of the final section. This will be the case if you selected the option "Smooth Exit" for the transfer duct. This option forces MOTA to set the area of the last transfer duct section outlet to be the same as the corresponding transfer port effective area, thus fixing its equivalent diameter.

The correct identification of the property smooth entry to or smooth exit from the duct is important when completing most of the duct screens. As an illustration, consider Figure 11 which shows a schematic of a single section transfer duct. The inlet diameter D1 , crankcase end is usually very close in value to the outlet diameter D2 , transfer port end , so in many cases, an equivalent parallel duct of constant circular cross section can be assumed.

The dimensions D1 and D2 are the diameters of a circle of the same area as the port openings. For D1 this may be most easily determined by using a rubbing of the inlet to the duct onto 1 mm square graph paper. Counting the squares gives an area which can be converted to a circle whose diameter is D1 using the formula:.

Notice that if the port is close to rectangular in shape with radiused corners the Tools Menu provides an option for evaluating the diameter of the circular section having the same area. If the end of a duct at the join with a piston port flares out markedly before it mates with the port, the duct should be marked as having a non smooth entry or exit, as appropriate, on the relevant duct screen.

Figure 11 depicts such a situation for a single section transfer duct. In addition to the dimensions D1 and LT , you will be asked for the equivalent diameter D2 immediately before the flaring occurs. For a single section transfer duct the corresponding length is the length of the transfer duct along its centreline from its beginning in the crankcase to its end at the piston face. The extension of this procedure to deal with inlet and exhaust ducts and with multiple section ducts follows naturally.

The need to divide a transfer duct into more than one section should rarely arise. The carburettor, any reed or rotary valve present, and associated ducting into the cylinder head or crankcase forms the inlet duct. It is assumed that the inlet duct consists of:. On the Engine Configuration screen, you indicate whether or not your engine contains an induction duct in addition to the normal inlet duct. Such a duct leads from the atmosphere to a still air box from which the normal inlet duct feeds.

If your engine has an induction duct, you need to indicate on the Induction Duct screen whether or not this duct contains an entry bellmouth.

You will also be asked to enter the volume of the induction still air box on this same screen. For all types of induction, you must specify whether or not there is an entry bellmouth. For piston port induction, there is an additional option box labelled smooth exit. A smooth exit prevails when the outlet area of the section of inlet duct in the cylinder barrel is the same as the inlet port area, that is, when the duct section is not flared into the port.

For reed valve and rotary valve induction, it is assumed that a smooth exit occurs and so the option box for this property is not displayed. Information regarding this last inlet duct section, referred to under the second bullet point above, must be entered here. For each type of induction, this comprises the duct diameter at the mounting flange and the length of the duct from its entry to the piston face piston port or to the reed valve petal tips reed valve or to the rotary valve disk face rotary valve.

In addition, for a piston port controlled engine, if you have specified a non-smooth exit into the inlet port the diameter at port input box will be active. This means that due to flaring, the duct area adjacent to the inlet port is different from that of the inlet port itself, and so you need to specify the equivalent diameter of the duct close to the port but immediately before the flaring.

For a rotary valve inlet port, the final section is the section between the mounting flange and the rotary valve disc face. For a piston ported engine, the final section is the section between the mounting flange on the cylinder barrel and the piston face. The assembly to the left of the mounting flange contains the Carburettor which may be fitted with a bellmouth at its intake end. Another duct section may exist between the carburettor and the barrel piston port induction or the crankcase flange reed valve or rotary valve induction.

For the configuration illustrated, the number of sections to be entered on the Inlet Duct screen is "3" and not "4" because details of the section adjacent to the reed or rotary or piston port are entered separately on this screen as previously described. The smooth entry option required for this screen has the same meaning as the smooth exit option on the piston port induction Inlet Duct screen and on the Transfer Duct screen s. Your choice will determine whether or not the Diameter at Port input box within the Exhaust Duct Section in Cylinder Barrel frame needs to be entered see Figure If the box is not dulled, you will need to enter the equivalent diameter of the exhaust duct at its entry from the cylinder but beyond the flaring at the port in the cylinder barrel.

You will always need to enter the diameter of this section at the cylinder barrel flange and the length of the section between this flange and the piston face. Although the MOTA engine simulator treats this section as an exhaust duct section, it must not be included in the Number of Duct Sections entered lower down the screen. If your engine is of the Box Muffler type, there will be only one section by default in the exhaust duct and you will not be asked for the number of sections in the exhaust system.

There will also be a tail pipe diameter and length to be provided, as well as a muffler volume. If you have chosen to model your engine with either an Integrated Muffler Box or Duct Model or with a Single Piece Expansion Chamber , you will be asked for the tail pipe length and diameter in addition to the details common to all exhaust systems.

The muffler volume will also be required for the Integrated Muffler Box Model. The Expansion Chamber screen will require the same details as for a Single Piece Expansion Chambe r engine, less the tail pipe details.

The Duct Muffler screen requires details of the muffler can and the protruding tail pipe. The muffler can may comprise several conical sections, just like the expansion chamber, so the relevant prompts are identical, as are those for the tail pipe which is assumed to pass through the rear face of the muffler can.

The screen contains a frame labelled Protrusions within the Muffler which provides two prompts. If the tail pipe length is zero, the corresponding input box will be inoperative dull , signifying just a hole in the rear of the muffler can, equal in diameter to the specified tail pipe diameter. However, if the tail pipe length is non-zero you are required to enter how far it protrudes into the muffler can.

When an Expansion Chamber Duct screen is displayed, the additional button Display Profile appears on the screen. Clicking this button displays a schematic of the expansion chamber and a table of dimensions which includes the cone angle and volume of each section.

The content of this screen can be sent to the printer. If this menu item is selected, you are asked to select a valid file such files will have the extension ".

The file selection procedure is identical to that for selecting a data file to edit section 4 , except that only Engine Performance Files will be listed. In MOTA this is defined on the basis of the trapped gas volume rather than the swept volume. V2 be the cylinder clearance volume, that is, the volume above the piston at TDC. V2 be the crankcase clearance volume, that is, the volume below the piston crown at BDC excluding the volume of the transfer duct s. By power output is meant the brake power output of the engine.

It is the power which is delivered at the crankshaft and represents the power available for the performance of useful work. Practically, values of engine power over a range of engine speeds are obtained by running the engine on a dynamometer.

By torque is meant the turning effect provided at the engine crankshaft. The units used are Nm metric and ft lbf imperial. In MOTA , the units used for the display of pressure is atmospheres atm.

Conversion factors to other metric and imperial measures of pressure are provided at the end of this manual. The brake mean effective pressure bmep is defined in terms of the brake power output. For metric units with V in c. This is referred to as the pumping power loss.

This value can be determined using sensitive equipment. The associated loss of power may then be calculated as. Friction losses occur in the engine bearings and during the motion of the piston in the cylinder. This friction power loss represents a reduction in the power available for the performance of useful work. The power developed in the engine cylinder is referred to as the indicated power output.

It can be determined using sensitive equipment. The associated indicated power output may then be calculated as. This is the amount of fuel consumed by the engine in an hour per unit of brake power output. The engine speed should be given when quoting this value. In MOTA, the inlet end of a duct is defined as the end of the duct into which the gas passing through the duct generally flows. For example, the inlet end of a transfer duct is the end in the crankcase.

Sometimes there is a small reversal of the flow at this end but most of the gas flowing in this duct enters from the crankcase. The outlet end of a duct is defined similarly. For example, the outlet end of a transfer duct is the end at the cylinder which is controlled by the piston.

During steady operation of an engine, for each duct, the net amount of gas flowing into the inlet end of the duct should be identical to that flowing from the outlet end of the duct over an engine cycle.

The property of a mathematical model of gas flow through a duct to reproduce this equality of inflow and outflow is known as mass conservation. There are several different models of gas flow which can be used in an engine simulation. The duct flow model in MOTA is one of a new generation of models which guarantees mass conservation. However, in order to achieve this conservation the model must be run for a sufficient number of revolutions see section 4.

If insufficient revolutions are performed during the simulation, mass conservation will not be achieved. In practice, mass conservation errors below 0. This error is negligible and is due to the fact that most simulations are run for only revolutions at each speed. The higher the number of revolutions, the better the mass conservation, but the longer the simulation will take to run.

Mr be the mass of air occupying the cylinder swept volume at atmospheric conditions. The delivery and exhaust flow ratios are provided in the MOTA output so that the user can check that sufficient revolutions have been completed to achieve mass conservation throughout the engine.

The delivery flow ratio is the flow ratio for gas flowing from the inlet duct into the engine. The exhaust flow ratio is the flow ratio for gas flowing out of the cylinder into the exhaust duct. In most cases these should differ by less than 0. In such cases, the simulations do not need to be re-run. The differences at these low speeds are caused by other factors and do not affect the integrity of the model.

In most cases this value is identical to the sum of the flow ratio s at the outlet end s of the transfer duct s. Mc be the mass of air occupying the cylinder swept volume at atmospheric conditions. In a two-stroke engine with piston controlled transfer and exhaust ports these ports are simultaneously open during a major part of the engine cycle.

A number of slightly different definitions of Scavenge Efficiency exists. That used by MOTA is based upon the contents, by mass, of the cylinder at the point when the exhaust port becomes fully closed. M2 be the mass of burnt gas remaining in the cylinder when the exhaust port closes. The smaller the value of M2 relative to M1 the greater the amount of fuel which is available for combustion and the higher the power output of the engine. The flow of gas within the engine is a dynamic process subject to changing pressures, velocities and temperatures.

In a well designed engine the exhaust gas will be extracted rapidly from the cylinder and the fresh charge from the crankcase will flow rapidly into the cylinder. There will be little mixing of the burnt gases with the fresh charge and the exhaust gas flow dynamics will prevent excessive loss of fresh charge into the exhaust system.

The Charging Efficiency provides a measure of the effectiveness of this process. M2 be the mass of air that would occupy the swept volume of the engine cylinder at atmospheric conditions. Whilst the amount of gas entering an engine duct over an engine cycle must be equal to that leaving it, the same is not true of the energy content heat energy plus kinetic energy of the gas.

As the gas travels through a duct, friction occurs when kinetic energy is converted to heat energy and heat energy is lost through the surface of the duct to the atmosphere and to any other cooling medium such as water which is present. Let E1 be the total energy of the gases passing from the engine cylinder to the exhaust system per cycle. E2 be the total energy of the exhaust gases passing to the atmosphere per cycle. The relevant data for each piston port type is displayed under this heading.

First, the port name, the number of ports, the port angular, arc and chord widths, the port height and for non profiled ports the top and bottom corner radii are displayed. Also, for a port pair, the bridge status is displayed. Next, for any bridged port pair, the bridge width, the radii at the top and bottom of the bridge and the effective maximum chord width are displayed. Finally, for each port type, the total area and the two attitude angles are displayed.

Output under this heading is provided only where at least one port type is defined by means of a sequence of equispaced arc width ordinates. For each such port the sequence of arc width ordinates are tabulated together with the corresponding chord widths and values of total cumulative port area.

The crank angle and the corresponding piston displacement from top dead centre at which each port starts to open and is fully open. If your engine contains a variably timed exhaust port, the timing details are listed. The number, length, inlet and outlet diameters, inlet and outlet cross section areas of each duct section in the engine. Note that each duct section is assumed to be uniformly tapered between its inlet and outlet diameters.

The cone angles and volumes are also listed for each expansion chamber section if your engine is of this type. When you select this option you will be asked to choose the name of a Graphics Output File these have the extension ".

The graphical information will then be read into MOTA from the selected file. Down the left hand side of your MOTA screen a number of buttons will be displayed. However, in the case of animated waves, you have to stop the animation by clicking the Wave Stop button before the two print buttons are made operative. If you have a colour printer the colour print option is particularly useful when printing power and torque curves where one or more overlays see section 6.

This is because the colour coding of the different curves is preserved. If the simulation run which produced the Graphics Output File involved four or more engine speeds the engine power and torque achieved at these speeds can be exhibited graphically and in such case these power curves are immediately displayed as the default.

If you run your engine simulations at four or more engine speeds, this option button is made operative. It allows you to display graphs of engine power and torque plotted against engine speed. The solid lines on the graph represent engine power and the dotted lines represent engine torque. When you select this option and also, when it is initially shown as the default display see above , four frames are added beneath the buttons at the left hand side of the MOTA environment.

The first Units frame allows you to change the units in which the graphs are displayed, that is either kW for the power and nm for the torque or hp for the power and ft lbf for the torque. The default display will correspond with the Output Units selection made on the Run Parameters screen when the corresponding Engine Data File was prepared. The second Display frame allows you to choose whether to display both power and torque, or either one singly.

The single display of torque curve s uses solid and not dotted lines. The third Overlay frame allows you to add and remove overlays from the graph. Adding an overlay displays a Windows dialogue box asking you to select a file for overlaying. Although only Graphics Output Files. The fourth Scales frame allows you to change the scales which were chosen by MOTA and, once such a change has been made you can make further changes or choose to restore the default scales to the display.

You may select up to 5 overlay files. You may remove an overlay at any time by clicking the Remove button. On doing this, a list of overlaid files is displayed and clicking a member of the list removes it from the display. Note: When you add an overlay file the current scales choice is not changed , even if this means that the newly displayed curve is clipped.

Of course you can change the scales at any time by clicking on Change in the Scales frame and then entering replacement scale limits of your choice. Alternatively you may elect to use the scales provided as the default by MOTA by clicking on Restore Default in the Scales frame, the scales so provided will display each of the selected curves in full. Also displayed within the plotting area of the power and torque curves is a black vertical bar which extends over the entire height of this area.

Where the bar intersects each curve a horizontal cursor is drawn and, to the right of the plotting area, the corresponding power and torque values and the engine speed are displayed. The position of this cursor bar can be controlled by the mouse left button, enabling the display of power and torque values at any chosen engine speed within the plotting range. Both click to move and drag mode control of the cursor bar are provided. Selecting this option allows you to view the propagation of Pressure, Velocity, Temperature, Density and Purity waves in each engine duct.

The display is animated in the sense that it displays the change in the relationship between the chosen variable and the distance down the selected duct several hundreds of times throughout an engine revolution. It repeats this display continuously for as long you wish.

You may alter the animation speed by changing the frame speed setting of the horizontal scroll bar displayed towards the bottom of the screen. When the waves button is clicked, a frame listing of all of the engine ducts appears. Selecting a duct displays another frame listing the various types of wave pressure, velocity, etc. Selecting a wave type results in the animation described above. You can change the wave type simply by selecting another one.

If you change the duct, the wave type frame initialises itself and you must again select a wave type to display the animation. After the still frame has been printed, you can click on Wave Start and the animation will continue. Because of the huge range and quality of VGA video adapters, it is impossible to ensure that the animated graphics will produce smooth and continuous images on all screens.

When images flicker and jump, adjusting the frame speed control on the display screen should rectify the problem. The difference between the pressure in the cylinder and the pressure at the cylinder end of the exhaust duct determines whether gas flows from the cylinder into the exhaust duct or into the cylinder from the exhaust duct.

In designing a two-stroke engine, you want to extract the combustion gases as quickly as possible and then plug the exhaust port with high pressure exhaust gas to prevent the in-coming fresh charge from the transfer port flowing out through the exhaust port before it is ignited. If your engine is fitted with an induction reed valve, this will display the variation of the reed petal tip lift with crankshaft angle. At any crankshaft angle, this is the sum of the delivery ratios see section 6.

Over one complete engine revolution, the amount of gas flowing into each engine duct should be identical to that flowing out of the duct at its other end. However, within an engine cycle, the variation with crankshaft angle of the gas flow into one end of a duct will be different from the variation of gas flow out of the duct at the other end. The delivery ratio at any point in time is just the mass of gas which has flowed through a particular duct end from the start of the engine revolution, divided by the mass of gas in the cylinder at ambient conditions with the piston at bottom dead centre.

Selecting this item provides a sub-menu list of the engine ducts. By clicking on a duct name you obtain the display of both the inflow and outflow delivery ratio curves for the selected duct. Note that for an engine with multiple transfer duct types, each duct will contribute to the total flow into the engine cylinder, so the Scavenge Ratio see section 6.

Selecting this item allows you to display, on the same screen, the variation of Pressure, Temperature, Purity and Density with crankshaft angle for the box you select from the sub-menu list. This sub-menu will always contain the choices Cylinder and Crankcase. Muffler for an engine with an Integrated Muffler and where the Box Model has been selected.

The choice Induction is also provided for an engine with an Induction Box. This selection provides a sub-menu which lists the engine ducts. Clicking on a duct name provides, on the same screen, plots of the variation in duct Pressure, Temperature, Velocity and Purity with crankshaft angle, at either end of the selected duct.

The functionality of this box is the same as the Windows example, but it has one additional feature. By holding down the control key , you can select up to a maximum of twelve Engine Data Files in the chosen folder by clicking the mouse over them. When you click the OK button, all of the Engine Data Files you have selected will be processed consecutively by the engine simulator.

Once the dialogue box disappears, the Engine Simulation screen should soon appear although on some lower speed computers this may take up to 20 seconds. You will notice that the title bar at the top of the screen is empty of all controls, so you are forced to interact with the simulator through the MOTA control buttons only. This is to prevent you from inadvertently shutting down the graphical environment whilst the simulation continues to run.

If something should go wrong, you can close the simulation by clicking the right mouse button over the vbsim icon in the bottom tool bar and selecting "close". During a simulation run, the name of the Engine Data File being processed is displayed beneath the various control buttons at the left hand side of the screen. Where more than one file has been selected for processing, the status of the entire selection is displayed under the headers Runs Completed, Current Run and Runs Queued.

Upon completion of a simulation run a message box is displayed at the top left hand side of the screen. This lists the names of the Engine Data Files which have been processed. During an engine simulation three control buttons are displayed which allow you to interact with the simulation. These are:. During the simulation, a number of key engine performance indicators is displayed numerically. Do you have a sports website?

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