Weihua Zhao

• Beijing Institute of Technology

Experiments were conducted to investigate the effects of different alcohol additives on the combustion and emission characteristics of a diesel engine. Diesel was blended with four higher alcohols (propanol, butanol, pentanol, and hexanol) with a blend ratio of 40% by volume. To evaluate the engine performance at different engine loads, four loads...

The main purpose of this work is to conduct detailed comparisons of spray behavior among four important components of gasoline and to investigate the effects of fuel properties and aerodynamic breakup on spray behavior under flash boiling conditions. Isooctane, hexane, pentane, and ethanol were used as test fuels. Pressure ratio (Rp) was used as an...

Due to their excellent fuel properties, butanol and hexanol are considered as two promising renewable fuels for diesel engine applications. The objective of this work is to investigate and compare the spray and combustion characteristics of butanol-diesel and hexanol-diesel blends under high-altitude conditions. A constant volume combustion chamber...

Due to the expansion of the global population and rapid economic growth, human activities at high-altitude regions are expected to grow. However, diesel engines are the main power sources for heavy-duty machinery, which can experience low combustion efficiency and high emissions due to the reduction of intake air mass. Adopting oxygenated fuels, su...

This work investigated the behaviors of single-component and multi-component sprays under different flash boiling intensities. Isooctane, hexane, ethanol, isooctane-hexane, and isooctane-ethanol mixtures were used as test fuels. The pressure ratio of the ambient pressure over saturation pressure (Rp) was used as the indicator of the superheated deg...

A significant number of landmasses on earth are above sea level where the ambient pressure is below 1 atm. With economy and population growth, the rapid expansion of human activities at these high-altitude regions is expected. However, the research on diesel engine combustion and emissions under low intake pressure conditions are limited, especiall...

A lateral swirl combustion system (LSCS) was designed to promote the spatial spray distribution through the spray wall impingement, and previous studies have established its combustion performance improvement in direct injection (DI) diesel engines. To verify that the improvement in combustion performance is due to the optimal wall-flow-guidance un...

In this study, wall-flow-guided combustion systems (WFGCS) were analyzed with the view to improve air use efficiency, fuel economy and emission performance in direct injection (DI) diesel engines. The results of previous study show that WFGCS facilitate favorable combustion and emission performance at low excess air coefficients. To quantitatively...

The lateral swirl combustion system (LSCS) can improve the air-use, fuel and emission performance of direct injection (DI) diesel engines. In this study, the differences in energy distributions between the LSCS and the double swirl combustion system (DSCS) were analyzed under different working conditions using a single-cylinder test system. A simul...

The lateral swirl combustion system was designed based on and to improve upon the traditional ω-type combustion system. Previous research has verified the outstanding combustion performance of the lateral swirl combustion system. In this study, to reveal the interaction mechanisms between the lateral swirl combustion chamber and spray jets, experim...

The direct injection (DI) diesel engines are the main power source in modern society. They are widely used in the fields of transportation, construction machinery, agricultural machinery, ships and small machinery. In the face of the challenges of energy saving and environment protection, high-efficient and low-pollution combustion mode has become...

Lateral-swirl combustion system(LSCS) can improve the fuel/air mixture formation and then decrease the fuel consumption and emissions in diesel engines.The mechanism of fuel/air mixing in a diesel engine with LSCS was analyzed through CFD simulation.The influences of fuel jet orientation angle and fuel spray angle on the LSCS combustion and perform...