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A combustion pressure measurement system is a major unit used to study combustion characteristics of an alternative fuel compared to a baseline fossil fuel. Many previous studies have used a Kistler make transducer connected to a Kistler charge amplifier to detect the combustion pressure inside the cylinder, but the prices are very high, more than 5,000 US$. Consequently, this technical paper provides some tips to properly assemble a combustion pressure measurement system with a much lower price and apply theoretical functions to convert raw data into combustion output variables. An AutoPSI pressure sensor connected with a charge amplifier and a PicoLog 1012 data logger was chosen, and the total cost was 2,250 US$. The pressure measurement unit was used to detect the combustion pressure of producer gas in a diesel engine operated in dual fuel mode. A venturi and a U-tube manometer were designed and fabricated to read producer gas flow rates based on the Bernoulli principle. Three different engine loads (i.e., 35%, 53%, and 70%) with gas flow rates (i.e., no gas, 10 kg/h, and 20 kg/h) were controlled to test the combustion pressure measurement system and the gas flow reader. The results highlighted that the combustion characteristics of the present study are in the same trends as those of existing studies. The combustion peak occurs lower and later with a higher gas flow rate, but an increase in engine load raises the peak pressure. This study contributes to offering technical tips to design a low-cost research facility. [ABSTRACT FROM AUTHOR]

Jatropha seed cake is a byproduct of biodiesel production. The seed cake can be used to make a producer gas that can be fumigated into a diesel engine operated on dual fuel mode without major modification. This paper intends to investigate the impact of Jatropha seed cake-derived producer gas mass flow rate on the performance and emission characteristics of a diesel engine operated on a dual fuel mode at a high engine speed of 3,000 rpm. The results highlight that the maximum diesel replacement rate reached 60% at a 20 kg/h gas flow rate when the engine was operated at medium engine load. An increase in gas flow rate augments the diesel substitution rate but decreases the electrical-thermal efficiency (ETE). At 70% of the full engine load, the specific diesel consumption declined from 0.337 to 0.185 kg/kWh when the gas was increased from zero to 20 kg/h. At this engine load, the ETE sharply fell off from 25% to 10.6% and 6.6% when the gas flow rate increased from zero to 10 kg/h and 20 kg/h, respectively. The electrical specific fuel consumption and electrical specific energy consumption, exhaust hydrocarbon (HC), carbon monoxide (CO), and carbon dioxide (CO2) emissions were found to be higher with an increase in gas flow rate. Unlike dual fuel engine operation at medium speed, the nitrogen oxides (NOX) emissions were consistent with an increase in gas flow rate. Based on the empirical findings, the dual producer gas-diesel engine should be operated at high engine load but not at a high engine speed of 3,000 rpm with a maximum gas flow rate of 20 kg/h. [ABSTRACT FROM AUTHOR]

Producer gas is a low energy density gaseous fuel converted from carbonaceous materials through a thermochemical process. The gas can be exploited to operate a diesel engine on a dual-fuel mode to partially reduce diesel fuel use. The present study intends to investigate the impacts of gas flow rate and diesel injection timing (DIT) on a diesel engine operated on a dual-fuel mode at a high engine speed of 3,000 rpm. The findings highlight that the peak pressure occurred later and was lower at a higher gas flow rate. The peak pressure was higher and advanced when the DIT was advanced and the engine load was increased. Large increases in CO2, HC, and CO concentrations were found in the dual-fuel mode, specifically at low loads. Unlike the findings using a medium engine speed, the specific NOX emissions were higher for the dual-fuel mode operation. Based on these empirical results, a dual-fuel engine should be operated at a high engine load and a gas flow rate of 10 kg/h. A slightly advanced DIT is required - roughly 3 degrees of crank angle. Furthermore, a dual producer gas-diesel engine should not be operated at the maximum gas flow rate. [ABSTRACT FROM AUTHOR]

A combustible gas converted from carbonaceous material through gasification technology can be used to operate the internal combustion engine. Dual fueling of the diesel engine to run on the gasified biomass has been extensively investigated; however, optimization of control factors to offset operating cost and diesel and biomass consumption has remained largely unexplored. This study aims to optimize operating settings, i.e., diesel injection timing, gas flow rate, and engine load to maximize the overall desirability of specific diesel consumption, specific Jatropha seed consumption, and operating cost. The finding highlighted that the maximum desirability of 82.29% for the sampling design was obtained at the injection timing of 9° before top dead center (BTDC), the gas flow rate of roughly 9 kg/h, and the high engine load. The concept of this study can also be applied to other bioenergy types. [ABSTRACT FROM AUTHOR]