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Diesel engine can be run with biodiesel which has the potential to supplement the receding supply of crude oil. As biodiesel possess similar physiochemical properties to diesel, most diesel engines can run with biodiesel with minimum modifications. However, the viscosity of biodiesel is higher, and the calorific value is lower than diesel. Therefore, when biodiesel is used in diesel engines, it is usually blended with diesel at different proportions. Use of 100% biodiesel in diesel engines shows inferior performance of having lower power and torque. Improving in-cylinder airflow characteristic to break down higher viscous biodiesel and to improve air-fuel mixing are the aims of this research. Therefore, guide vanes in the intake runner were used in this research to improve the performance of diesel engine run with biodiesel.

Exhaust gases from diesel engines can be an adequate source of energy to run a bottoming Rankine cycle to increase the overall efficiency of the engine as it contains a significant portion of input energy. In this research, an automotive diesel engine was tested to estimate the available energy in the exhaust gas. Shell and tube heat exchangers were used to extract the heat from the exhaust gas and the performance of the two shell and tube heat exchangers were investigated with parallel and counter flow arrangements using water as the working fluid. The results obtained were below satisfactory as these heat exchangers were purchased from the marketplace and not optimized for this particular application. Thus attempts were made to optimize the design of the heat exchanger by computer simulation using the available experimental data.

Due to depletion of crude oil and exhaust emissions associated with internal combustion engine, biodiesel, neat vegetable oil and waste cooking oil are identified as potential alternative fuels to run on diesel engines. However, the viscosities of these fuels are higher than diesel and can be grouped as higher viscous fuel (HVF). Currently, diesel engines fuelled by HVF experience problems of reduced power and torque besides increased fuel consumption and in-cylinder carbon deposit. These are mainly due to poor combustion as HVF is less prone to evaporate and mix with air. To reduce these problems, a technique to improve the air-fuel mixing in diesel engine fuelled by HVF using Guide Vane Swirl and Tumble Device (GVSTD) is presented in this paper. Validated simulation model for a diesel engine was developed using Solidworks and ANSYS-CFX before 12 GVSTD models were imposed in front of the intake runner with the vane twist angle varied from 3° to 60°.

This paper focuses on waste heat recovery (WHR) system, which is an efficient technology to reduce fuel and vehicle carbon dioxide (CO2) emissions per kW of power produced. Wide variations of power of a vehicle make it difficult to design a WHR system which can operate optimally at all powers. The exhaust temperature from the engine is critical to design a WHR system. Higher the temperature higher will be the gain from the WHR system. However, as power drops the exhaust temperature drops which makes the WHR system perform poorly at lower powers. In this research, a small diesel truck engine was used to design a WHR system to produce additional power using a Rankine cycle (RC). The WHR system was designed at the rated power and speed of 42.8 kW and 2600 rpm, respectively. At this design point, around 15% additional power improvement was achieved resulting around 13% break specific fuel consumption reduction.

The performance of a compression ignition (CI) engine run with alternative fuel is inferior to when it is run with petro-diesel resulting in lower power, higher fuel consumption and higher carbon deposits. This is due to the poorer properties of the alternative fuel for the CI engine compared to petro-diesel, for instance, higher viscosity. Due to this factor, this research has grouped these fuels as higher viscous fuels (HVFs). In order to solve or reduce the problem of higher viscosity, this paper presents research that has sought to improve the in-cylinder airflow characteristics by using a guide vane so that the evaporation, diffusion, mixing and combustion processes can be stimulated eventually improving or at least reducing the problem. The in-cylinder airflow was studied using ANSYS-CFX with the help of SolidWorks. Firstly, the validated base model replicated from the generator of a CI engine was prepared.

Fast consumption of fossil fuels is demanding researchers to find few potential alternative fuels that meet sustainable energy demand in the near future with least environmental impact. Future energy system needs to be cost-efficient, renewable, and safe to handle. Biodiesel is expected to be the future energy source that meets all the environmental norms. The use of biodiesel in Internal Combustion (IC) engines represents an alternative clean energy source compared to hydrocarbon fuels that generate emissions such as carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOX), Sulfur Oxides (SO) and particulate matters (PM). This paper describes the importance of Palm Oil Diesel (POD) as an alternative fuel source for diesel engines. Simulations are carried out with ANSYS FORTE software with POD. The engine chosen is a 26-kW diesel-gen-set. The engine geometry is drawn in SOLIDWORKS using dimensions of the actual diesel engine.

The waste heat recovery (WHR) system appears to lower overall fuel consumption of the engine by producing additional power and curtailing greenhouse emissions per unit of power produced. In this project, a 25.5 kW diesel engine is used and simulated, which has an exhaust temperature of about 470°C. During optimization of the heat exchangers, the overall weight of the heat exchangers is kept low to reduce the final cost. Additionally, the overall pressure drops across the superheater, boiler, and economiser are kept at around 200 kPa to expel the exhaust gas into the atmosphere easily. To accomplish high heat-transfer across the heat exchangers, the pinch temperature of the hot and cold fluids is kept above 20°C. In this project, under the design constraints and available heat at the exhaust gases, the WHR system has enhanced the power and reduced the break specific fuel consumption by around 6.2% and 5.8%, respectively at 40 bar pressure.

To comply with the new Corporate Average Fuel Economy (CAFE) standards, automakers are expected to increase the average fuel economy of their vehicles to 54.5 miles per gallon from the current 24.8 miles per gallon by 2025. This research aims at proposing a feasible solution to narrow down the gap between the current and expected fuel economy of the vehicles, yet maintaining the engine’s original performance. A standard model of the KTM 510 cc single cylinder, fuel injected, internal combustion engine (IC) engine is modelled and simulated in Ricardo Wave software package to map the stock engine performance and specific fuel consumption at wide open throttle (WOT). The baseline simulation model is validated against the experimental readings with 98% accuracy.