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To meet stringent reduction in exhaust emission and improving internal combustion engine fuel efficiency, have forced the designer to optimize auxiliary systems like lubrication and cooling. This paper describes the experimental and simulation verification of a 1.3 litre water cooled engine lubrication system. The lubrication circuit model is built in Ricardo Ignite software. The simulation model preparation steps using 3D-CAD model is explained in paper. Engine main bearing and connecting big-end bearing leakage maps are evaluated using Ricardo Valdyn software which is capable of simulation engine crank-train multi body dynamics along with bearing oil behavior. The pressure and flow distribution at various locations are predicted using simulation model. These simulation predictions are experimentally verified. It is observed acceptable correlation between simulation and experimental values.

Aluminium alloy material cylinder head is a popular choice for any air-cooled internal combustion engine. But when it is exposed to higher temperature, it is vulnerable for its loss in strength. It becomes imperative to maintain cylinder head temperature well below acceptable temperature limit. Efficient cooling system play a vital role to achieve this objective. In the present work, an air-cooled diesel engine is converted into compressed natural gas (CNG) engine configuration for 25kVA genset configuration. A 1D gas-exchange model is created to generate the thermal boundary conditions required for Computational Fluid Dynamics (CFD) analysis. A steady-state 3D Conjugate Heat Transfer (CHT) model, that uses the predicted in-cylinder temperatures as a spatially varying boundary condition, is created to predict the convective heat transfer between engine fins and cooling air. A Blower Fan is modelled using the Moving Reference Frame (MRF) approach.

This paper presents a one-dimensional (1-D)/three-dimensional (3-D) simulation methodology for uprating a diesel engine to reduce production costs and improve fuel economy. The case study is carried out for a baseline multicylinder direct injection (DI) naturally aspirated (NA) diesel engine of 2945 cc, which meets the Central Pollution Control Board (CPCB)-II emission regulations and is used in a 25 kVA genset application. An uprated version of this NA engine is designed to replace a 30 kVA genset turbocharged engine, eliminating the expense of the turbocharger while reducing fuel consumption. The 1-D computational model was calibrated on the 25 kVA base engine and produced a good agreement with the airflow rate, power, brake-specific fuel consumption (BSFC), cylinder pressure, and oxides of nitrogen (NOx) emission levels.

EGR flow within individual cylinder as per requirement has a great importance which controls the performance and emissions of the diesel engine. The work presented here, elaborates the mixing process of EGR in the manifold with the fresh charge entering into intake manifold and then into cylinder. The study is carried on our three-cylinder diesel engine. For the simulation of such highly pulsating flow, the boundary conditions were generated from 1D model & in the back end the 3D CFD is used to solve the EGR mixing in a transient phase. The mixing at each cylinder port is evaluated using the Air and CO2 mass fraction at outlet of each intake port. Being a transient nature of valve operation, the EGR distribution within the manifold observed stabilized in 9 cycles. It was observed that the flow pulsations at the EGR inlet have large influence on the EGR distribution.

In this work, the ignitjion delay of bio-diesel and its blends with diesel at atmospheric pressure and temperature 8500C has been studied. The results are compared to those for diesel oil. Specifically, the suspended fuel droplet is inserted into a hot combustion chamber containing atmospheric air at temperatures which varied from 6250 - 8500C. The fuel droplet is suspended on the fine silica fibre wire of diameter 550 micron. It is mounted on rod and inserted in the hot combustion chamber at atmospheric condition. The ignition of the droplet is observed by optical circuit (optical sensor) and recorded by CRO. The ignition time is determined for calculating ignition delay. The results are plotted on the ignition delay ln(t) - 1/Temperature, K-1 coordinates to obtain the value of Activation Energy, EA. It has been found that the value of Activation Energy, EA is 44.3kJ for bio-diesel and 53.4kJ for diesel.

Laminar burning velocity is a fundamental measurement describing how a flame propagates into quiescent unburned mixture ahead of the flame at a specified pressure and temperature. Laminar burning velocity of bio-diesel air mixture has been studied in a spherical bomb, using the pressure - time records. Initial pressure, temperature is varied to cover a range from 1 bar - 4 bar and 443K-523K respectively. The range of measurements covered the equivalence ratio from 0.8 to 1.2. Pressure-time records have been used to calculate the flame velocity, burned gas fraction, flame position etc., using a simplified, two zone thermodynamic model, assuming equilibrium composition and homogenous mixture for the burned gases. It is also assumed frozen composition and isentropic compression for the unburned mixture.

The advent of new non-road transient cycle for upcoming off-road emission norms in India requires attention on engine thermal management also. A simulation prediction capability is evaluated assessing engine coolant circuit behavior in 3.3 liter turbocharged engine. The cylinder head and block jackets are modeled in Ricardo Vectis for generating pressure drop and flow distribution study. A complete engine cooling circuit is modeled using Ricardo Ignite software and calibrated with experimental results for steady state as well as transient modes on various engine speeds. Once model calibration is established within acceptable correlation limit of maximum 10% deviation, it is coupled with non-road transient cycle simulated in Ricardo Ignite. The whole drive cycle simulated flow conditions line coolant temperature, flow rate and radiator heat dissipation is compared with experimental measured values. The correlation is also very below acceptable limit.

The paper presents the investigation on the Engine fuel efficiency improvement using one-dimensional (1-D) simulation software Ricardo WAVE. The study is carried out for a baseline multicylinder direct-injection turbocharged diesel engine of 2945 cc displacement, meeting the Central Pollution Control Board (CPCB)-II emission norms. Initially, the base simulation model is calibrated and observed for a good correlation between the experimental and simulation results for parameters like airflow rate, engine power, brake-specific fuel consumption (BSFC), and cylinder pressure. There is also an acceptable agreement between the predicted and actual measurement values for nitrogen oxides (NOx) emission. Now different combinations of turbochargers and combustion-related hardware are optimized in 1-D simulation, and the best combination is also verified experimentally.

It is easy to identify flow induced noise on a flow bench or engine testing, but it is also equally essential to understand the fundamental mechanisms of fan noise generations. A methodology for optimizing cooling fan noise using 3-D CFD technique is presented in this paper. This work is an extension of Reference Nain, A. [2], where cooling fan dimensions like blade shape, number of blades, blade diameter etc. are optimized for achieving fuel efficiency targets. Any design modification in a fan should also be validated for any cause of noise generation. Initially engine noise sources are identified experimentally in anechoic chamber. Each noise source is categorized in order of their dominance on overall noise level. The cooling fan system impact is also extracted from overall noise spectrum.

Hybridization of off road vehicles is in its early phase but it is likely to increase in coming years. In order to improve fuel economy and overall emission of the 3.3 litre tractor model, various kinds of engine hybridization is studied. This paper presents a methodology to predict vehicle fuel consumption and emission using 1-D software by coupling Ricardo Wave and Ricardo Ignite. Initially, An acceptable agreement within 5% deviation between simulation and experimental is established for engine steady state points, both for engine performance and NOx emission parameters. Engine fuel consumption and emission maps are predicted using Ricardo WAVE model. These maps are used as an input to IGNITE model for predicting cumulative fuel consumption. Same calibrated model is used further for studying idle start stop and fully hybrid P0 type hybrid architecture. The hybrid P0 type involves idle start stop, e-boost and regeneration.

In order to reduce engine development timing and cost, a numerical calculation used to evaluate valve train systems. This paper discusses the work done on kinematic and dynamic analysis of Valve Train (VT) system of a diesel engine by using 1-D Ricardo Valdyn software. The goal is to meet optimum intake, exhaust valve timing requirement, maximize, valve open area and 30% over-speed requirement. Valve train model is prepared and inputs like mass and stiffness are estimated from 3-D model and finite element analysis, respectively. Simulation model is used for predicting valve bounce speed, valve displacement, cam-follower contact stress and strain in the rocker arm. Initially, Kinematic analysis is carried out to study the change in valve motion characteristics such as cam contour radius, tappet contact eccentricity etc. Further to this, dynamic analysis is carried out to assess forces and stresses on valve train components.

The paper presents the investigation of the engine fuel efficiency improvement using one-dimensional (1D) simulation software Ricardo Wave. The study is carried out for a baseline multicylinder direct-injection naturally aspirated diesel engine of 2945 cc meeting CPCB-II emission norms. Initially base simulation model is calibrated and good correlation is observed between experimental and simulation results for parameters like airflow rate and engine power cylinder pressure. Engine breathing capability, i.e. volumetric efficiency, is improved by optimizing intake pipes, intake ports and cam events. Cam-lobe profile is optimized keeping consideration of gen-set/tractor application. Optimum hardware improved engine pumping losses which results in better fuel efficiency on various load points. It meets CPCB-II emission norms.

In the present work, a 4 cylinder, 5.3 liter, Direct Injection Diesel engine producing 140 kW rated power was upgraded to a higher power rating of 170 kW complying with Euro V emission norm. The exhaust after treatment strategy was changed from Exhaust Gas Recirculation (EGR) to Selective Catalytic Reduction (SCR). 1-D thermodynamic simulation was used to simulate the performance. The simulation model was calibrated for performance parameters with the test results available from the 140 kW engine. This model was used to carry out the turbocharger matching for the 170 kW engine using the Simplified and Full Turbocharger model. A parametric study was carried out for the variables like Compression ratio, Start of Combustion shift and Compressor pressure ratio in view of the target Brake Specific Fuel Consumption (BSFC) and Peak firing pressure limits. The finalized model parameters were used for carrying out a Full throttle and Part throttle performance at selected operating points.

Emission norms are introduced to limit exhaust pollutants from vehicular engines to improve and control ambient air quality. Thermodynamic simulation results showed the possibility of upgradation from Euro-2 to Euro-3 emission norms using a low pressure inline fuel injection pump. Geometric parameters of piston bowl, injection nozzle were adjusted and the combustion parameters like swirl start of injection, controlled injection and jet penetration were fine tuned to achieve the emission norms using the cost effective inline fuel injection pump. This fuel injection system is tolerant to indifferent fuel quality as it is lubricated by engine oil and the clearances within the pump do not demand exceptional lubricity or cleanliness of the fuel. The exhaust is polished off soluble organic fractions, carbon monoxide and hydrocarbons using a lightly loaded diesel oxidation catalyst that is tolerant to 500 ppm sulphur in fuel. Data from 20 engines showed emission is consistent.