• Energy Research

One of the factors that affect the performance of the value‐regulated lead acid (VRLA) battery is gel electrolyte. To address this, a gel polymer electrolyte comprising halloysite nano‐clay in a poly(vinyl alcohol) matrix is formulated and the electrochemical performance is studied. Interaction between halloysite nano‐clay and poly(vinyl alcohol) is confirmed by Fourier transform infrared spectroscopy (FTIR). To optimize the concentration of gel electrolytes, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) are utilized. Galvanostatic charge‐discharge (GCD) tests are performed on a prototype battery comprising of an optimized gel electrolyte. The battery shows the highest discharge capacity of 6.858 μAh at 7.5 μA cm−2 current density and achieves admirable discharge capacity retention of 87.5% after 500 cycles. Hydrogen‐bonded halloysite nano‐clay and poly(vinyl alcohol) can be employed as gel electrolytes in VRLA batteries.

The present work aims to investigate the consequences of pilot fuel (PF) multiple injections and hydrogen manifold injection (HMI) on the combustion and tailpipe gas characteristics of a common rail direct injection (CRDI) compression ignition (CI) engine operated on dual fuel (DF) mode. The CI engine can perform on a wide variety of fuels and under high pilot fuel (PF) pressure. Pilot fuel injection (PFI) is achieved at TDC, 5, 10, and 15ºCA before the top dead center (bTDC), and divided injection consists of injecting fuel in three different magnitudes on a time basis and PF is injected into the engine cylinder at a pressure of 600 bar. In this work, the hydrogen flow rate (HFR) was fixed at 8 lpm constant and producer gas was inducted without any restriction. The investigational engine setup has the ability to deliver a PF and hydrogen (H2) precisely in all operating circumstances using a separate electronic control unit (ECU). Results showed that diesel-hydrogen enriched producer gas (HPG) operation at maximum operating conditions provided amplified thermal efficiency by 4.01% with reduced emissions, except NOx levels, compared to biodiesel-HPG operation. Further, DiSOME with the multi-injection strategy of 60 + 20+20 and 50 + 25+25, lowered thermal efficiency by 4.8% and 9.12%, respectively compared to identical fuel combinations under a single injection scheme. However, reductions in NOx levels, cylinder pressure, and HRR were observed with a multi-injection scheme. It is concluded that multi-injection results in lower BTE, changes carbon-based emissions marginally, and decreases cylinder pressure and heat release rate than the traditional fuel injection method.

During recent decades, considerable effort has been expended world-wide to reduce dependency on petroleum fuels for power generation and transportation through the search for suitable alternative fuels that are environmentally friendly. In this respect, vegetable oils are a promising alternative to diesel fuel. However, the high viscosity, poor volatility and cold flow characteristics of vegetable oils can cause some problems such as injector coking, severe engine deposits, filter gumming and piston ring sticking and thickening of lubrication from long-term use in diesel engines. These problems can be eliminated or minimised by transesterification of the vegetable oils to form monoesters. Although transesterification improves the fuel properties of vegetable oil, the viscosity and volatility of biodiesel are still worse than those of petroleum diesel fuel. The performance of a diesel engine with such biodiesel operation can be improved further with the concept of the low heat rejection (LHR) engine. In th...

This paper reports an investigation of the use of biodiesel in a common rail direct injection (CRDI) engine.

Abstract This present work highlights the influence of injection timing (IT), injector opening pressure (IOP) and compression ratio (CR) on the combustion characteristics of a diesel engine operated on renewable and sustainable fuels. In this research work an effort has been made to enhance the combustion of fuel combination in a diesel engine with addition of carbon free hydrogen and in the direction of lowering the exhaust emission levels. Experimental investigations have been carried out to study the combustion and exhaust characteristics of a single cylinder, four stroke, direct injection (DI) diesel engine operated on Tri-fuel mode using Honge seed oil methyl ester (HsOME) as the injected fuel and producer gas-hydrogen mixture as the inducted fuel. . To minimize the number of experiments full factorial design (FFD) has been adopted. The response surface methodology (RSM) based quadratic models obtained through FFD have been established between the parameters and proposed characteristics. With hydrogen addition, response surface analysis showed that increasing CR, IOP with advanced IT significantly improves the combustion of HsOME-producer gas fueled diesel engine in terms of the enhanced brake thermal efficiency (BTE) and reduced carbon based emission levels (Smoke opacity, Carbon monoxide, Hydrocarbon) except the nitric oxide (NOx) emissions. Further combustion parameters such as Ignition delay (ID), and combustion duration were lowered with hydrogen addition, advanced IT, increased IOP and CR. In addition peak pressure and heat release rate (HRR) were found to be higher compared to base fuel combination.

Polyelectrolyte complex membranes (PECMs) were prepared by combining sodium carboxymethyl cellulose (NaCMC) and gelatin (Ge) with variations in the Ge content in the NaCMC matrix. Characterization methods, such as infrared spectroscopy (FTIR), wide-angle X-ray diffraction (WAXD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), contact angle analysis (CA), and universal testing machines (UTM) were used to investigate the physicochemical studies of the prepared membranes. The pervaporation characteristics of membranes with Ge content were investigated using an azeotropic mixture of water and bioethanol. The obtained data revealed that the membrane with 15 mass% of Ge (M-3) showed a maximum flux of 7.8403 × 10−2 kg/m2·h with separation selectivity of 2917 at 30 °C. In particular, the total and water flux of PECMs are shown as very close to each other indicating that the fabricated membranes could be employed to successfully break the azeotropic point of water–bioethanol mixtures. Using temperature-dependent permeation and diffusion data, the Arrhenius activation parameters were calculated, and the obtained values of water permeation (Epw) were considerably smaller than bioethanol permeation (EpE). Developed membranes showed the positive heat of sorption (ΔHs), suggesting that Henry’s sorption mode is predominant.

Abstract In the present work, effect injection timing (IT) on the modified dual fuel (DF) engine performance with effective utilization of biodiesel and gaseous fuel combinations is reported. Biodiesel prepared Ceiba Pentandra oil called Ceiba Pentandra oil methyl ester (CPNTOME) and its B20 blend (CPNTOME B20) are used as pilot injected fuels while the biogas (raw and purified) is used as the inducted fuel in the modified DF engine. Hence, the present research focus on the study of DF engine performance fuelled with liquid and gaseous fuel combinations. Meanwhile, the effect of IT on modified DF engine performance is investigated. Brake thermal efficiency (BTE), carbon monoxide (CO), hydrocarbon (HC) and smoke emissions were found to be less besides higher emissions of NOx were observed. Combustion parameters such as ignition delay (ID), and peak pressure (PP) are analysed. The DF engine operated on renewable fuel combinations in DF mode can cover the way for partial substitution of fossil fuel along with reduction in greenhouse gas emissions. Advancing the IT improves the DF engine performance and reduces the smoke, CO and NOx emissions.

Abstract Energy is an essential requirement for economic and social development of any country. Sky rocketing of petroleum fuel costs in present day has led to growing interest in alternative fuels like vegetable oils, alcoholic fuels, CNG, LPG, Producer gas, biogas in order to provide a suitable substitute to diesel for a compression ignition (CI) engine. The vegetable oils present a very promising alternative fuel to diesel oil since they are renewable, biodegradable and clean burning fuel having similar properties as that of diesel. They offer almost same power output with slightly lower thermal efficiency due to their lower energy content compared to diesel. Utilization of producer gas in CI engine on dual fuel mode provides an effective approach towards conservation of diesel fuel. Gasification involves conversion of solid biomass into combustible gases which completes combustion in a CI engines. Hence the producer gas can act as promising alternative fuel and it has high octane number (100–105) and calorific value (5–6 MJ/Nm 3 ). Because of its simpler structure with low carbon content results in substantial reduction of exhaust emission. Downdraft moving bed gasifier coupled with compression ignition engine are a good choice for moderate quantities of available mass up to 500 kW of electrical power. Hence bio-derived gas and vegetable liquids appear more attractive in view of their friendly environmental nature. Experiments have been conducted on a single cylinder, four-stroke, direct injection, water-cooled CI engine operated in single fuel mode using Honge, Neem and Rice Bran oils. In dual fuel mode combinations of Producer gas and three oils were used at different injection timings and injection pressures. Dual fuel mode of operation resulted in poor performance at all the loads when compared with single fuel mode at all injection timings tested. However, the brake thermal efficiency is improved marginally when the injection timing was advanced. Decreased smoke, NO x emissions and increased CO emissions were observed for dual fuel mode for all the fuel combinations compared to single fuel operation.

In the current study, an effort is carried out to study the influence of pentanol as low reactive fuel (LRF) along with diesel and Thevetia peruviana methyl ester (TPME) as high reactive fuels (HRF) in reactivity controlled compression ignition (RCCI) engine. The experiments are conducted on dual fuel engine at 50% load for RCCI mode of operation by varying pentanol percentage in injected fuels. The results revealed that RCCI mode of operation at 10% of pentanol in injected fuels exhibited higher brake thermal efficiency (BTE) of 22.15% for diesel and pentanol fuel combination, which is about 9.1% and 27.3% higher than other B20 and pentanol, B100 and pentanol fuel combinations respectively. As the percentage of pentanol increased in injected fuels, hydrocarbon (HC) and carbon monoxide (CO) emissions are increased while nitrogen oxide (NOx) and smoke emissions are decreased. Among various fuel combinations tested diesel and pentanol fuel combination gives lower HC, CO and smoke emissions and higher NOx emissions. At 10% pentanol in injected fuels, the highest heat release rate (HRR) and in-cylinder pressure are found for diesel and pentanol fuel combinations compared with other fuels.