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Alcohols are potential blending agents for diesel that can be effectively used in compression ignition engines. This work investigates the use of n-butanol as a blending component for diesel fuel using experiments and simulations. Dodecane was selected as a surrogate for diesel fuel and various concentrations of n-butanol were added to study ignition characteristics. Ignition delay times for different n-butanol/dodecane blends were measured using the ignition quality tester at KAUST (KR-IQT). The experiments were conducted at pressure of 21 and 18 bar, temperature ranging from 703-843 K and global equivalence ratio of 0.85. A skeletal mechanism for n-dodecane and n-butanol blends with 203 species was developed for numerical simulations. The mechanism was developed by combining n-dodecane skeletal mechanism containing 106 species and a detailed mechanism for all the butanol isomers.

Fuel injection is one of the most important processes in the GDI engine operation. Depending when the fuel is injected in the GDI engine, it can either work in homogeneous or stratified charge mode. In case of real engine operation, fuel injector gets heated due to heat transfer from the in-cylinder hot burnt gases. This can significantly affect the spray characteristics and ultimately the engine performance. In the present work, engine like hot injector body conditions have been created in a constant volume spray chamber. Five different temperatures conditions (23 °C, 100 °C, 150 °C, 200 °C and 250 °C) were created to study the effect of hot fuel conditions. Schlieren and Shadowgraph techniques were used to capture the vapor and the liquid phase of Isooctane, whereas droplet size information was measured using the Phase Doppler Particle Analyzer (PDPA). Results showed that with increase in fuel temperature, spray collapsed towards the injector axis due to flash boiling of the fuel.

Liquid sloshing noise from an automotive fuel tank is becoming increasingly important during frequent accelerating/decelerating driving conditions. It is becoming more apparent due to significant decrease in other noise sources in a vehicle, particularly in hybrid vehicles. As a step toward understanding the dynamics of liquid sloshing and noise generation mechanism, an experimental study was performed in a partially filled rectangular tank. A systematic study was performed to understand the effects of critical parameters like fill level and acceleration/deceleration magnitude. Response parameters like dynamic pressure, dynamic force, dynamic acceleration and sound pressure levels along with high speed video images were recorded. The proposed experimental setup was able to demonstrate major events leading to sloshing noise generation. These events in the sloshing mechanism have been analysed from the dynamic sensor data and correlated with high speed video images.

Use of bio fuels in a regular spark ignition engine is becoming common in several countries to reduce the dependence on fossil fuels and overall generation of green house emissions. Alcohols such as methanol and ethanol are blended with gasoline when SI engines are considered. Advanced direct injection stratified charge engine technology has gained lot of interest due to its merits over conventional port fuel injection engine. Since the technology is significantly spray controlled, fuel injection and spray behavior under different thermodynamic conditions plays a very important role in successful engine operation. Present work was carried out to understand the spray behavior of isooctane and three alcohols under engine-like pressure and temperature conditions. Selected alcohols were ethanol, isobutanol and n-butanol. A six holes solenoid injector was used for this study.

With significant decrease in the background noise in present day automobiles, liquid slosh noise from an automotive fuel tank is considered as a major irritant during acceleration and deceleration. All major international OEMs and their suppliers try to reduce sloshing noise by various design modifications in the fuel tank. However, most major activities reported in open literature are primarily based on performing various CAE and experimental studies in isolation. However, noise generation and its propagation is a multiphysics phenomenon, where fluid mechanics due to liquid sloshing affects structural behaviour of the fuel tank and its mountings which in turn affects noise generation and propagation. In the present study a multiphysics approach to noise generation has been used to predict liquid sloshing noise from a rectangular tank.