Experimental investigation and RSM-based optimization of combustion characteristics in an ABE-fueled HCCI engine
FUEL, cilt.430, 2027 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 430
- Basım Tarihi: 2027
- Doi Numarası: 10.1016/j.fuel.2026.141625
- Dergi Adı: FUEL
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Gazi Üniversitesi Adresli: Evet
Özet
Homogeneous charge compression ignition (HCCI) combustion is an advanced low-temperature combustion (LTC) strategy that combines the high thermal efficiency of compression ignition (CI) engines with the low nitrogen oxide (NOx) and soot emission advantages of spark ignition (SI) engines. However, difficulties in controlling self-ignition timing and a narrow operating range are among the main issues that limit the practical application of HCCI engines. In this study, the effects of n-heptane and acetone-butanol-ethanol (ABE) blends on the combustion, performance, and emission characteristics of an HCCI engine were investigated both experimentally and statistically. In the experiments, ABE mixtures at 20%, 40%, and 60% ratios were added to nheptane fuel, and engine tests were conducted at engine speeds ranging from 800 to 1200 rpm and lambda values ranging from 2.5 to 3.5. In the experimental design and analysis processes, response surface methodology (RSM) based on the central composite design (CCD) was employed, and a total of 15 experimental combinations were conducted. The variable response parameters evaluated were engine torque, brake specific fuel consumption (BSFC), exhaust temperature, maximum pressure rise rate (MPRR), start of combustion (CA10), combustion phase (CA50), combustion duration (CD), indicated thermal efficiency (ITE), as well as carbon monoxide (CO) and hydrocarbon (HC) emissions. As a result of RSM optimization, the optimal operating conditions were determined to be an ABE ratio of 51.64%, an engine speed of 800 rpm, and a lambda value of 2.65. Based on the validation tests conducted under optimal conditions, the maximum deviation for the response parameters was found to be 2.63%. The findings indicate that n-heptane/ABE blends increase combustion stability in HCCI engines, reducing fuel consumption and providing highly efficient combustion behavior.