The engine models, designed with various packages, have been validated by comparing the results computed with reference results presented in [23]. Comparing the results obtained with the reference results of [23], calculations give delay in the maximum pressure point (this shift is about 10 degrees for RW and LESoft calculations, and it is about 8 degrees for MESC calculations), although the maximum pressure level, predicted with various packages, is close to reference data (discrepancy is about 3% for all packages). Varying the 50% burn point simply shifts the entire curve forward or backward. Resultant the energy needed does not locate in the designed position push the piston. the effective compression ratio does. Valve overlap contributes to the intake Both the piston and head surface area are assumed to be equivalent to the area derived from the bore diameter with multipliers of this area allowed in the Woschni heat transfer model. In the course of the work, the scientists identified general principles of creating digital twins of engines, created unique software, and patented it. have seen the AFR lean out (increase) with RPM, which would indicate a deficiency. engine file and save it with your own name. This is needed for piston In MESC calculations, the fraction of blow-by is specified with initial value of 0.8. Negative valve overlapping (NVO) consists of closing both valves for a period of time [5–8]. These results are shown in Table 7. At present, we are up to version 5 of the engine modelling software, with version 6 in the works. finite element Newtonian flow dynamics, with friction and flow momentum. Masses in grams are also Additonal Features over Basic and Plus * Calculation of data every .1 to .4 crank … height, head gasket thickness, piston valve relief's, etc., so it should be quite Current variable valve timing systems (VVT) are limited to designed valve profile due to the dimension of lobe. Simulation duration sets the number of cycles for the engine to run before settling on a solution. The combustion duration is defined as the number of crank degrees between 10% and 90% of mass fraction burnt. Detailed verification and validation of submodels describing chemical composition of combustion products, heat transfer, friction and combustion processes, and gas dynamics of intake and exhaust systems have been performed. it runs. The new fuel injection strategy by injecting a portion of fuel during the negative valve closing interval and inject the rest in the intake stroke was also examined in [15]. The starter cranks the engine over a few revolutions to determine the test By considering the engine control in real driving condition, the in-house engine simulation package is the only one that allows running simulations with changing speed and other operating parameters throughout a simulation period that is required. The results, computed with three packages, are presented in Figure 15. The most frequent differences are the presence of water vapour, carbon dioxide, and argon in the atmospheric air. Not all the details of the LS7 engine could be obtained, such as the actual piston GUI shows up with various performance and analysis plots to display. to 1972 this was the standard to rate engines called “SAE Gross.”  After 1972, automakers Calculations in the unburned zone continue without addition of heat due to combustion. The pressure distributions are started with crank angle of −180 degrees when the piston is at BDC. Unlike static and dynamic compression ratios, which don’t change with RPM, Max Boost Pressure”, and “Intercooler Temp Reduction.”  A supercharged example, the This is also takes into account when sub-model calculates the enthalpy. Reducing the lobe separation, Exhaust Efficiency shows how effectively the engine is able to expel the spent exhaust 2013, Article ID 401643, 21 pages, 2013. https://doi.org/10.1155/2013/401643, 1School of Mechanical and Automotive Engineering, Faculty of Science, Engineering and Computing, Kingston University, Friars Avenue, Roehampton, London SW15 3DW, UK. The piston is connected to a crank by way of a connecting rod that protrudes out the opposite open end of the cylinder and connects to a crank. These inputs are port flow coefficients, valve lift per crankshaft rotation, combustion and heat transfer modeling (types of models to be used for representing the combustion and heat transfer processes and the surface areas and temperatures of various components within the cylinder, phasing of cylinder firing with respect to TDC). The heat transfer coefficient for each surface is obtained from the Colburn analogy of heat and momentum transfer and is directly linked to the effective velocities. The idea behind LIVC is to burn the mixture in a lower combustion temperature and hence to reduce nitrogen oxide (NOx). The pressure peaks, predicted with RW and MESC calculations, are in a good agreement. using clay for the final assessment. Engine Analyzer Pro Engine Analyzer Pro v3.9 Our Top of the line Engine Simulation Software, with advanced Finite-Difference, wave tuning intake and exhaust simulation. In term of engine control, spark plug can be controlled by ECU to decide whether the mixture needs to be ignited by spark. simplicity, a sample timing ramp was used here with a total advance of 30 degrees Some intuition is used to determine the parameters due to the large difference in engine operating speed and difference in engine type. The simulation is set up with default “acceptable” clearance of The pressure increases when the piston moves up to compress the air and fuel mixture. Cylinder connects to multiple flow elements via valves and usually require numerous submodels in order to correctly represent the desired system. Software package for numerical simulation of gasdynamics phenomena in pipelined systems. This way allows the user to enter a cylinder pressure profile obtained from testing, internally derive a heat release profile using the applied heat transfer model and thermodynamic properties, and output a fuel mass burn profile for combustion calculations. Other types of sensors, such as lambda sensor, engine temperature sensor, or knock sensor are used on closed loop control configuration. complete engine cycle. Combustion products are a mixture of some gases. The “flow” model, implemented in RW, predicts convective heat transfer from gases to combustion chamber walls, and its spatial and cyclic temporal variations are driven by the instantaneous mean and turbulent gas motions [3]. Lotus Engineering Software user menu, Lotus Group plc, 2011. Intake and Exhaust Valve Lashes were included to ECU computes the new set of parameters to make fine adjustments to actuators providing better engine performance. As this version of the software is offered as freeware Lotus Engineering will not guarantee that they are able to respond to users support inquiries. A portion of exhaust gas will suck back to the combustion chamber while the exhaust valve is opening, and hence increase the mixture pressure and temperature. There are some researches dedicated to modifications of cylinder geometries by the aid of mechanical parts to vary the compression ratio when needed [4, 5]. The pressure distributions, predicted with three packages, are presented in Figure 11. The geometric parameters and operating parameters of engine are shown in Table 2, and some other input parameters, which are specific for this test, are presented in Table 5. Main differences Instantaneous and mean levels of heat radiation are functions of the volume and distribution of burning gas, amount of soot present in the burning gas, combustion chamber geometry, and surface emissivity and temperature. The simulation was validated using several engine configurations, by comparing with GT-POWER Engine Simulation Software GT-POWER is the industry standard engine performance simulation, used by all major engine manufacturers and vehicle OEMs . The effective compression ratio can be affected by the valves timing. Ideally, you want the average RPM throughout the shifts to match the RPM The intake port is connected with the intake valve (“PVAL1” element). Calculations with LESoft are based on one-zone model allowing prediction of averaged temperature in the engine cylinder. The conditions within these elements are calculated at each crank angle by solving the mass equation and the energy equation derived from the first law of thermodynamics. The knock control system consists of knock sensor, signal processing unit, and the knock controller, which is integrated in ECU. The flexibility of the different packages is investigated, and the accuracy of ICE models is compared. This one is 8 degrees advanced, Also entered is engine setup information, such as head time. Advance RPM”, and remaining constant from then on. one of those things like piston to valve clearance that can destroy an engine if The time displayed is the simulation or engine time in seconds at full throttle The profiles of averaged temperature are shown in Figure 12. The first GUI that comes Supercharged 427 engine, to help with the validation and to show how typical values Blow-by occurs when a portion of gas escapes through the gap between piston and cylinder wall into the crankcase [22]. The intake temperature and pressure are 300 K and 1 bar. determined by weighing the front and rear separately at your local truck stop weigh Length of the connecting rod located between the engine piston and the crankshaft. The engine model consists of the cylinder (“CYL1” element), and intake and exhaust networks each of which is designed using three elements representing connector, port, and valve. Engines fitted with electronic control provide flexibility to adjust the engine parameters to achieve certain performance. If all the plots are selected, then the following plots are displayed: Since the intake and exhaust lobe profiles are the same for this particular cam, either vacuum or mechanical. The heat transfer coefficients of coolant and cylinder head are constant value, and conductivity of material is specified by choosing material used. The pressure rises due to the heat added to the compressed gas. In any case, to reasonably Engine cycle simulation model follows the changing thermodynamic and chemical state of the working fluid through the engine’s intake, compression, combustion, expansion, and exhaust processes.