One-dimensional numerical investigation on multicylinder gasoline engine fueled by micro-emulsions,CNG,and hydrogen in dual fuel mode

This research work is the novel state-of-the-art technology performed on multi-cylinder SI engine fueled compressed natural gas,emulsified fuel,and hydrogen as dual fuel.This work predicts the overall features of performance,combustion,and exhaust emissions of individual fuels based on AVL Boost simulation technology.Three types of alternative fuels have been compared and analyzed.The results show that hydrogen produces 20%more brake power than CNG and 25%more power than micro-emulsion fuel at 1500 r/min,which further increases the brake power of hydrogen,CNG,and micro-emulsions in the range of 25%,20%,and 15%at higher engine speeds of 2500-4000 r/min,respectively.In addition,the brake-specific fuel consumption is the lowest for 100%hydrogen,followed by CNG 100%and then micro-emulsions at 1500 r/min.At 2500-5000 r/min,there is a significant drop in brake-specific fuel consumption due to a lean mixture at higher engine speeds.The CO,HC,and NOx emissions significantly improve for hydrogen,CNG,and micro-emulsion fuel.Hydrogen fuel shows zero CO and HC emissions and is the main objective of this research to produce 0%carbon-based emissions with a slight increase in NOx emissions,and CNG shows 30%lower CO emissions than micro-emulsions and 21.5%less hydrocarbon emissions than micro-emulsion fuel at stoichiometric air/fuel ratio.

Darcy-Forchheimer mangetized flow based on differential type nanoliquid capturing Ohmic dissipation effects

Hydromagnetic nanoliquid establish an extraordinary category of nanoliquids that unveil both liquid and magnetic attributes.The interest in the utilization of hydromagnetic nanoliquids as a heat transporting medium stem from a likelihood of regulating its flow along with heat transportation process subjected to an externally imposed magnetic field.This analysis reports the hydromagnetic nanoliquid impact on differential type(second-grade)liquid from a convectively heated extending surface.The well-known Darcy-Forchheimer aspect capturing porosity characteristics is introduced for nonlinear analysis.Robin conditions elaborating heat-mass transportation effect are considered.In addition,Ohmic dissipation and suction/injection aspects are also a part of this research.Mathematical analysis is done by implementing the basic relations of fluid mechanics.The modeled physical problem is simplified through order analysis.The resulting systems(partial differential expressions)are rendered to the ordinary ones by utilizing the apposite variables.Convergent solutions are constructed employing homotopy algorithm.Pictorial and numeric result are addressed comprehensively to elaborate the nature of sundry parameters against physical quantities.The velocity profile is suppressed with increasing Hartmann number(magnetic parameter)whereas it is enhanced with increment in material parameter(second-grade).With the elevation in thermophoresis parameter,temperature and concentration of nanoparticles are accelerated.

Numerical investigation to evaluate the effects of gravity and pressure on flame structure and soot formation of turbulent non-premixed methaneair flame

In this study,a turbulent non-premixed(diffusion)methane-air flame has been investigated computationally to analyze the influences of pressure and gravity on flame structure and sooting characteristics between 1 and 10 atm.The simulation has been conducted in a 2-D axisymmetric computational domain using the finite volume-based computational fluid dynamics(CFD)code.The interaction of turbulence and chemistry is modeled by considering the steady laminar flamelet model(SLFM)and the GRI Mech 3.0 chemical mechanism.The radiative heat transfer calculation is carried out by considering the discrete ordinate(DO)method and the weighted sum grey gas model(WSGGM).The semi-empirical Moss-Brookes model is considered to calculate soot.The impact of gravity on flame and sooting characteristics are evaluated by comparing the normal-gravity flames with the zero-gravity flames.The effect of soot and radiation on flame temperature is also examined.The results show a close agreement with the measurement when both soot and radiation are included in the numerical modeling.The rates of soot formation,surface growth,and oxidation increase with increased operating pressure,regardless of gravity.Zero-gravity flames have a higher soot volume fraction,a wider soot-containing zone,a higher CO mass fraction,and a lower flame temperature than normal-gravity flames while maintaining constant pressure.In normal-gravity flames,the CO mass fraction decreases with pressure,whereas it increases with pressure rise in flames of zero gravity.Flames of zero gravity appear taller and broader compared to the flames of normalgravity for a fixed pressure.An increase in pressure significantly reduces the flame length and width in normal-gravity flames.However,the pressure elevation has little effect on the shape of a zero-gravity flame.The outcomes of the present study will assist in fully understanding the combustion and sooting characteristics of turbulent diffusion flames that will help design and develop high-efficiency,pollutant-free combustion devices and fire suppression systems for space application.