Kavita Gupta
Independent Researcher
India
Abstract
Variable Valve Timing (VVT) technology plays a crucial role in improving the thermal efficiency and performance of Internal Combustion (IC) engines by optimizing valve operation timing according to engine load and speed. This paper reviews the principles of VVT, its types, and its impact on engine thermal efficiency. A detailed experimental study using a VVT-equipped single-cylinder IC engine is presented, focusing on combustion characteristics and thermal efficiency improvements compared to a conventional fixed-timing engine. Statistical analysis illustrates significant gains in brake thermal efficiency and fuel economy. The results affirm that VVT mechanisms contribute to substantial enhancements in IC engine thermal performance, reducing fuel consumption and emissions without compromising power output. The study concludes by highlighting the potential of VVT technology in meeting stricter environmental regulations and fuel economy standards prevalent until 2020.
Keywords
Variable Valve Timing, Thermal Efficiency, Internal Combustion Engine, Brake Thermal Efficiency, Combustion Optimization
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