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Abstract Dynamic stresses exist in parts of a catalyst muffler caused by the vibration of a moving vehicle, and it is important to clarify and predict the vibration response properties for preventing fatigue failures. Assuming a vibration isolating installation in the vehicle frame, the vibration transmissibility and local dynamic stress of the catalyst muffler were examined through a vibration machine. Based on the measured data and by systematically taking vibration theories into consideration, a new prediction method of the vibration modes and parameters was proposed that takes account of vibration isolating and damping. A lumped vibration model with the six-element and one mass point was set up, and the vibration response parameters were analyzed accurately from equations of motion. In the vibration test, resonance peaks from the hanging bracket, rubber bush, and muffler parts were confirmed in three excitation drives, and local stress peaks were coordinate with them as well.

Abstract The paper presents a complete description of the design and manufacturing of a Carbon Fiber/epoxy mold with an embedded Carbon Fiber resistor heater, and the mold performances in terms of its surface temperature distribution and thermal deformations resulting from the heating. The mold was designed for manufacturing aileron skins from Vacuum Bag Only prepreg cured at 135°C. The glass transition temperature of the used resin-hardener system was about 175°C. To ensure homogenous temperature of the mold working surface in the course of curing, the Carbon Fiber heater was embedded in a layer of a highly heat-conductive cristobalite/epoxy composite, forming the core of the mold shell. Because the cristobalite/epoxy composite displayed much higher thermal expansion than CF/epoxy did, thermal stresses could arise due to this discrepancy in the course of heating.

Mechanical and thermal properties of the rubber compounds of a tire play an important role in the overall performance of the tire when it is in contact with the terrain. Although there are many studies conducted on the properties of the rubber compounds of the tire to improve some of the tire characteristics, such as the wear of the tread, there are a limited number of studies that focused on the performance of the tire when it is in contact with ice. This study is a part of a more comprehensive project looking into the tire-ice performance and modeling. In this study, to understand the effect of different rubber compounds on the tire performance, three identical tires from the same company have been chosen. The tires’ only difference is the material properties of the rubber. Two approaches have been implemented in this study.

Abstract Addition of hydrogen to hydrocarbons in premixed turbulent combustion is of technological interest due to their increased reactivity, flame stability and extended lean extinction limits. However, such flames are a challenge to reaction modelling, especially as the strong preferential diffusion effects modify the physical processes, which are of importance even for highly turbulent high-pressure conditions. In the present work, Reynolds-averaged Navier-Stokes (RANS) modelling is carried out to investigate pressure and hydrogen content on methane/hydrogen/air flames.

Abstract The rapid utilization of fossil fuels has triggered the finding of alternative renewable fuel that replaces or reduces the consumption by alternative fuels for fueling compression ignition (CI) engines. One such renewable fuel is ethanol which can be manufactured from biomass. The present study details the utilization of an optimum amount of ethanol in CI engine by modifying the operating parameters. It was already published in the previous paper that 45% ethanol can be utilized along with diesel using 10% butanol as cosolvent. This fuel is also meeting the minimum requirement with respect to properties as per ASTM standards. This experimental study was performed to investigate the influence of modifying the engine operating parameters on the performance, combustion, and emission parameters fueled with the blend containing 45% ethanol under various load conditions.

Abstract In the last few years, reactivity-controlled compression ignition (RCCI) mode combustion has gained researchers’ attention due to its superior performance, combustion, and emission characteristics compared to other low-temperature combustion (LTC) strategies. In this study, RCCI mode combustion investigations were carried out to explore the effects of exhaust gas recirculation (EGR) and intake charge temperature (ICT) on combustion, performance, and emission characteristics of a mineral diesel/methanol-fueled engine. In this study, constant engine speed (1500 rpm) and load (3 bar brake mean effective pressure [BMEP]) were used to perform engine experiments. The premixed ratio (rp) of methanol was varied from rp = 0 to rp = 0.75, where rp = 0 represents the baseline compression ignition (CI) mode combustion. At all rp, EGR rate and ICT were varied from 0 to 30% and 40° to 80°C, respectively.

Abstract Combustion engines and liquid fuels are likely to continue playing a central role in freight transportation with renewable fuels reducing carbon emissions. Ethanol and methanol are future renewable fuels with a knock resistance that make them suitable for heavy-duty (HD) spark ignition (SI) engines. This simulation work focuses on the potential for improving the efficiency of an ethanol- and methanol-fueled HD SI engine using early intake valve closing Miller valve timing. With Miller valve timing, the expansion ratio and thermodynamic efficiency can be increased while maintaining the same effective compression ratio. However, Miller timing requires increased boost pressure to retain the same trapped air mass and also suffers from reduced in-cylinder turbulence.

Abstract In this experimental study, a novel combustion technique, “reactivity-controlled compression ignition” (RCCI), has been investigated using alcohols acting as low-reactivity fuel (LRF) and mineral diesel acting as high-reactivity fuel (HRF). Combustion experiments were performed in a single-cylinder research engine at a constant engine speed of 1500 rpm and a low engine load of 3 bar brake mean effective pressure (BMEP). RCCI combustion is a practical low-temperature combustion (LTC) concept, which was achieved using three primary alcohols: Methanol, Ethanol, and Butanol in different premixed ratios (rp = 0.25, 0.50, and 0.75) with mineral diesel. Results showed a relatively superior performance and emissions characteristics of RCCI combustion compared to conventional compression ignition (CI) combustion. The influence of LRF was visible in RCCI combustion, which exhibited a more stable combustion compared to the baseline CI combustion.

Corrigendum - The word "Differ" in the title should be corrected to "Different". The correct title is: Rapid Methodology to Simultaneous Quantification of Different Antioxidants in Biodiesel Using Infrared Spectrometry and Multivariate Calibration.

Abstract The aim of this work is to quantify three different antioxidants in biodiesel - Santoflex, baynox, and tocopherol-using Middle Infrared (MIR) spectroscopy and chemometrics. For the construction of the models, 28 samples containing an antioxidant in the range of 0.1 to 500 mg/kg in biodiesel were used. We developed three models based on PLS 1 multivariate calibration method to quantify each of the three antioxidants separately and a model based on PLS 2 method to quantify simultaneously all the antioxidants. All models were compared to the values of root mean square error of calibration (RMSEC) and validation (RMSEP). For the baynox, santoflex, and tocopherol antioxidants quantification using PLS 1, the values of RMSEC and RMSEP were 37.2, 18.8, 9.0 mg/kg, and 26.7, 21.1, 68.6 mg/kg, respectively.

Abstract In this article, a comparative study of hydrogenated vegetable oil (HVO) and Diesel was performed in two constant volume combustion rigs and an optical accessible compression-ignited chamber (OACIC). Ignition, combustion, and nitric oxide (NO) emissions were studied under constant ambient gas density of 16.4 kg/m3, 21% vol oxygen concentration, and two different injection pressures of 800 and 1000 bar. Emission of NO was measured only in the OACIC, while a line-of-sight soot temperature distribution by applying two-color pyrometry was investigated in both setups. In general, the HVO as alternative fuel showed shorter ignition delay and less NO emission than Diesel for both injection pressures. Due to difference in the molecular structure, soot temperature of biofuel flames had narrower temperature spectrum than conventional fuel. Moreover, this study reveals the significance of wall-jet interaction for utilization of the biofuel.

Abstract The transportation industry is currently in a transition toward the use of zero-emission vehicles; however, reaching it will take a considerable amount of time. In the meantime, a diesel powertrain will remain the workhorse for most heavy-duty transportation. In order to reduce the engine’s environmental impact, biofuels, such as biodiesel, are used as drop-in fuels or fuel blends. The use of drop-in fuels may create challenges for the fuel system since sticky deposits can precipitate and cause injector malfunctioning or premature fuel filter plugging. It has been concluded in the past that these deposits have been caused by soft particles. In this article, soft particles created through the degradation of biodiesel and their effect on filters are studied. The article aims to analyze fuel filters and investigate the materials responsible for soft particle separation. The study includes three pre filters and three main filters that are commercially available truck filters.

Abstract In modern diesel fuel a proportion of biodiesel is blended with petro-diesel to reduce environmental impacts. However, it can adversely affect the operation of nonwoven coalescing filter media when separating emulsified water from diesel fuel. This can be due to factors such as increasing water content in the fuel, a reduction in interfacial tension (IFT) between the water and diesel, the formation of more stable emulsions, and the generation of smaller water droplets. Standard water/diesel separation test methods such as SAE J1488 and ISO 16332 use monoolein, a universal surface-active agent, to simulate the effects of biodiesel on the fuel properties as part of water separation efficiency studies. However, the extent to which diesel/monoolein and diesel/biodiesel blends are comparable needs to be elucidated if the underlying mechanisms affecting coalescence of very small water droplets in diesel fuel with a low IFT are to be understood.

Abstract Rubber elements present highly nonlinear mechanical properties affected by frequency and amplitude of excitation, prestrain and temperature, etc. Finite element (FE) models and lumped parameter models can be distinguished in the development of constitutive models of rubbers. Based on the concept of overlay model, different kinds of viscoelastic, or frequency-dependent models, and elastoplastic/friction, or amplitude-dependent models, are compared in terms of their modelling approach, parameters identification process and applications. Prestrain-dependent models and temperature-dependent thermo-mechanical models are also reviewed, including some special models which are not based on the concept of the overlay model. Experimental and computational studies of cylindrical bushings subjected to coupled deformation modes are analyzed and discussed.

Abstract To protect ship equipment of river and sea transport, it is suggested to use polymeric protective coatings based on epoxy diane oligomer ED-20, polyethylene polyamine (PEPA) curing agent and filler, which is a departure from industrial production. Thus the purpose of the work is analysis of major dependency of the properties on the content of fillers that allowed to revealed the critical filler content (furnace black) in composites to form a protective coating with the required set of characteristics. The infrared (IR) spectral analysis was used to investigate the presence of bonds on the surface of particles of the PM-75 furnace black, which allows us to assess the degree of cross-linking of the polymer. The influence of the content of dispersed furnace black on the physicomechanical and thermophysical properties and the structure of the protective coating is investigated.

Abstract A non-pneumatic tire (NPT) has a lot of applications and is a viable option for the future, as they do not possess the problem of blowouts and air pressure maintenance. In these NPTs, the air-filled part is replaced by a flexible structure capable of withstanding the weight of the vehicle and delivering optimum performance. In the present study, endeavors have been made to analyze the rolling performance of NPTs by considering a light commercial vehicle as an application. The NPTs with three different configurations are studied by considering three hyperelastic material models for the hexagonal spoke structure and shear band under various loading conditions. Initially, static analysis for the models is conducted in two dimension (2D) and three dimension (3D) to validate the results, and these models were further extended to rolling analysis. The rolling resistance and slip ratios are obtained and compared in both 2D and 3D analyses.

Abstract Nylon polymer with an optimal blend of Kevlar, fiberglass, and high-speed, high temperature (HSHT) Fiberglass offers improved characteristics such as flexural strength, wear resistance, electrical insulation, shock absorption, and a low friction coefficient. For this reason, the polymer composite manufactured by combining HSHT, Kevlar, and fiberglass with nylon as base material will expand the uses of nylon in the aerospace, automotive, and other industrial applications related to ergonomic tools, assembly trays, and so forth. The proposed work was carried out to investigate the continuous fiber reinforcement (CFR) in nylon polymer using a dual extrusion system. Twenty experimental runs were designed using a face-centered central composite design (FCCD) approach to analyze the influence of significant factors such as reinforcement material, infill pattern, and fiber angle on the fabricated specimen as per American Society for Testing Materials (ASTM) standards.

Abstract Driving schedule of every vehicle involves transient operation in the form of changing engine speed and load conditions, which are relatively unchanged during steady-state conditions. As well, the results from transient conditions are more likely to reflect the reality. So, the current research article is focused on analyzing the biofuel-like lemon peel oil (LPO) behavior under real-world transient conditions with fuel injection parameter MAP developed from steady-state experiments. At first, engine parameters and response MAPs are developed by using a response surface methodology (RSM)-based multi-objective optimization technique. Then, the vehicle model has been developed by incorporating real-world transient operating conditions. Finally, the developed injection parameters and response MAPs are embedded in the vehicle model to analyze the biofuel behavior under transient operating conditions.

Abstract This study demonstrates the defossilized operation of a heavy-duty port-fuel-injected dual-fuel engine and highlights its potential benefits with minimal retrofitting effort. The investigation focuses on the optical characterization of the in-cylinder processes, ranging from mixture formation, ignition, and combustion, on a fully optically accessible single-cylinder research engine. The article revisits selected operating conditions in a thermodynamic configuration combined with Fourier transform infrared spectroscopy. One approach is to quickly diminish fossil fuel use by retrofitting present engines with decarbonized or defossilized alternatives. As both fuels are oxygenated, a considerable change in the overall ignition limits, air–fuel equivalence ratio, burning rate, and resistance against undesired pre-ignition or knocking is expected, with dire need of characterization.