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Hydrogen is considered as one of the potential alternate fuel and when compared to other alternate fuels like CNG, LPG, Ethanol etc., it has unique properties due to absence of carbon. In the current work, Hydrogen engine of 2.5 L, four cylinder, spark ignited Turbocharged-Intercooled engine is developed for Mini Bus application. Multi-point fuel injection system is used for injecting the hydrogen in the intake manifold. Initially, boost simulation is performed to select the optimum compression ratio and turbocharger. The literature review has shown that in-order to get the minimum NOx emissions Hydrogen engines must be operated between equivalence ratios ranging from 0.5 to 0.6. In the present study, full throttle performance is conducted mainly with the above equivalence ratio range with minimum advance for Maximum Brake Torque (MBT) ignition timing. At each operating point, the performance, emissions and combustion parameters are recorded and analyzed in detail.

This report describes work performed jointly by Mahindra & Mahindra and IIT Delhi, including both simulations and single-cylinder engine development for three wheeler application, to quantify the effects of various parameters on the performance and NOx emission of an internal combustion engine fuelled by hydrogen. AVL Boost software was used to simulate the experimental conditions, by using Vibe 2-Zone combustion and Woschni heat models, together with kinetic equations for emission calculations. Developed AVL Boost Model was validated against the test result from a modified single cylinder CNG engine for three wheeler application fuelled with Hydrogen by comparing the performance and NOx emission at the same operating conditions. A good agreement was obtained between the results of the Boost Model and Experimental results.

DC/DC converters are switching regulator specially used for voltage level conversion application, and one of crucial entity for fuel cell. In absence of which fuel cell real world application is difficult to conceive. Numerous works have been contributed using PID controller to regulate the output voltage and improve DC/DC converter dynamic performance. Due to switching operation, nonlinearity causes complexity in DC/DC converter control. In present article, PID controller optimization for a DC/DC buck converter is devised specifically for fuel cell application. Linearization and averaging technique is employed to generate State Space Average Model (SSAM) of DC/DC buck converter. PID controller weight factor's reference value i.e. Kp, Ki and Kd are selected based on values obtained by traditional Ziegler-Nichols method. Fine-tuning of PID weight factors are accomplished using Genetic Algorithm.

The main objective of the project is to develop the hydrogen-fuelled vehicles for transport application. Exhaustive lab tests on engine & vehicle was done to access the hydrogen (H₂) behavior at varying operating conditions. Fifteen such hydrogen-fuelled vehicles were developed by Mahindra with integration of the optimized engine, fuel storage system, fuelling system and safety features to demonstrate these hydrogen vehicles. These vehicles are refueled at a dedicated hydrogen-refueling facility. Detailed calibration was done with hydrogen for meeting the performance and emissions characteristics of the engine. In this experimental investigation Electronic Control Unit (ECU)-based timed manifold injection system was developed. Hydrogen is injected before the intake manifold and the quantity of hydrogen injection is depending on the load, speed and operating conditions.

This article is focused on the development of hydrogen fuelled engine with detailed exposure on its derivation from base Compressed Natural Gas (CNG) engine to discuss the phenomenon on backfiring, control strategies (to avoid knocking and backfiring) and its performance, emission characteristics. In this work, timed manifold injection system was developed to have efficient control over the fuel supply. To achieve the best performance and emission out of the engine, governing parameter like injector pulse width and ignition timing were optimized at full load, part load and idling. For comparison of the results with the same engine experiments were also conducted with base fuel CNG and gasoline using the conventional fuel supply system. It was experimentally observed that engine when fuelled with Hydrogen (H2) produces less maximum power compared to CNG and gasoline.

The present study is to evaluate the performance & emission characteristics of biodiesel on a 2.6L turbocharged common rail direct injection engine powered on Sports utility vehicle (SUV). The effect of neat biodiesel and its blends with diesel at various ratios was evaluated. The study was extended to analyze combustion characteristics using pressure time history with various blends. This paper elaborate the effect of biodiesel on both engine & vehicle level. Impact on fuel economy, noise level and drivability was also discussed. Experimental results revealed significant reduction of power throughout the operating range while running with biodiesel. So the engine injection strategy was optimized specially for biodiesel to obtain the desired performance & emission. Engine performance results were discussed based on the analysis of heat release, which made it possible to give more precise information about the combustion process.

Biodiesel is a nontoxic, biodegradable and renewable fuel with a potential to reduce engine exhaust emissions. Biodiesel used for the current work is jatropha methyl ester (JME). Earlier research, when biodiesel used in neat form, showed deterioration of performance when compared with diesel. The scope of current work is to match the existing diesel performance in all aspects, when the vehicle is fuelled by neat biodiesel (Jatropha). Matching diesel performance with biodiesel was done by remapping electronic control module. This results in power increase, but the vehicle emissions and noise level tends to increase. So tradeoff between performance and emission is achieved by optimizing the engine parameters. Comparative performance was taken with normal diesel and biodiesel in neat form. Different engine characteristics like torque, power, thermal efficiency, exhaust temperature and noise along with emission such as HC, CO, NOx, and Smoke were studied.

The methyl esters of vegetable oils known as biodiesel, are receiving increasing interests because of their potential for low environmental impact as an alternative fuel to diesel vehicles. There is not much data collected on engine and vehicles using biodiesel from non-edible oils, particularly on new generation Common Rail Diesel Engines (CRDe).The present experimental study reports the performance and exhaust emissions of a CRDe engine using 10% & 20% (by vol.) blends of Jatropha and Karanja oil methyl ester (JCME & KOME) with conventional diesel fuel. To begin with studies were conducted on a SUV, powered by Euro III / BSIII optimized ECU controlled 2.6 l Common Rail Diesel engine (CRDe) configured with a diesel oxidation catcon and exhaust gas recirculation system. The impact of using biodiesel blends was studied in terms of cold startability, drivability, acceleration, max speed, gradeability, fuel economy and exhaust emissions.

Biodiesel is being explored as a sustainable renewable fuel for vehicles in India due to mounting foreign exchange expenditure to import crude petroleum. Significant amount of research and development work is being undertaken in India to investigate various aspects of biodiesel utilisation in different types of engines. This study is an effort to jointly investigate the use of biodiesel (B100) in an unmodified BS-III compliant sports utility vehicle (SUV) by a consortium of academia (IIT Kanpur) and Industry (M&M) to realistically assess whether biodiesel is compatible with modern engine technology vehicles. Two identical vehicles were operated in tandem using biodiesel (B100) and mineral diesel (B00) respectively for 30,000 kilometers in field conditions. The lubricating oil samples were collected and detailed analysis for assessing the comparative effect of new fuel (B100) vis-à-vis mineral diesel was carried out.

The role of transfer port geometry in improving scavenging near the spark plug with consequent improvement in cyclic variations and irregular combustion have been studied through engine tests by recording the pressure-time data of many cycles with the original and modified ports on a 150cc crankcase compressed shnurle loop scavenged two stroke engine under various operating conditions. The results show that there is an optimum upsweep angle which gives reduction in cyclic variations and lowering of delivery ratio at which irregular combustion starts. The side sweep angle does not seem to affect much. The improvement seems to be closely related to the reduction in the duration of the initial phase of combustion and its variations.

Causes leading to cyclic variations and resulting in misfiring in a two-stroke cycle spark-ignited engine are explained through analytical validation of experimentally observed behaviour. Experimental observation of pressure-time (P-t) histories of individual cycles suggests that cyclic variations are dependent on combustion delay and initial flame development and that local factors near the spark plug are mainly responsible for this. This has been used to build a hypothesis to explain the behaviour of poor cycles and to predict theoretically, using a quasi-dimensional thermodynamic model, the P-t histories of the individual cycles for comparison with the experimental results. It is observed that the gross mixture quality of each cycle is not an important factor for initial flame development, which depends mainly on the local conditions around the spark plug. For the engine under study, the reasons for the behaviour of poor cycles was attributed to poor scavenging near the spark plug.

Two-stroke cycle engines have excessive speed fluctuations and poor part-throttle fuel economy as a consequence of cyclic combustion variations and irregular combustion, leading to misfiring. This study is to identify the nature of cyclic variations and the regime of irregular combustion in order to understand the possible causes for this phenomena. Studies were carried out on a 150 cc two-stroke cycle S.I. engine. Statistical evaluations of peak pressure(Pmax) and indicated mean effective pressure (imep) were used to characterize cyclic variations and irregular combustion. A parametric study on the effect of air fuel ratios, spark timing, engine speed, spark plug locations, throttle setting, and cylinder head shape on cyclic variations were carried out. The study has identified the regimes of stable combustion, irregular combustion and misfiring.

Methanol (90% methanol + 10% gasoline) when used as a fuel in a 2-stroke spark ignition (SI) engine gave rise to abnormal combustion even at a low compression ratio. The regime of engine operation in which abnormal combustion occurs was identified and the effects of engine parameters such as mixture strength, compression ratio, ignition timing, combustion chamber geometry etc. were studied. Analysis of pressure-time histories of engine cycles when abnormal combustion occurred revealed that abnormal combustion at higher loads is similar to knocking in four-stroke engines. At light loads the nature of abnormal combustion was different. The CFR octane rating of methanol does not correlate with actual anti-knock quality in two-stroke engine combustion. Comparison with primary reference fuels indicated that the two-stroke engine has a very high severity. The hot residual gases seem to have a major role on onset of abnormal combustion.