IRREVERSIBILITY ANALYSIS IN Al2O3-WATER NANOFLUID FLOW WITH VARIABLE PROPERTY

The present numerical work deals with the optimization of the micro-channel heat sink using irreversibility analysis. The nanofluid of Al2O3-water with the different nanoparticles concentration and the temperature-dependent property is chosen as a coolant. The flow is considered as fully developed, steady, and laminar in the constant cross-section of circular channels. Navier-Stokes and energy equations are solved for a single-phase flow with total mass flow rate and heat flow rate as constant. The objective functions related to the frictional and heat transfer irreversibilities are framed to assess the performance of the micro-channel heat sink. The optimum channel diameter corresponding to the optimum number of channels is determined at the lowest total irreversibility for both constant property solution and variable property solution. Designed optimum diameter is observed maximum for 2.5% Al2O3-water nanofluid with μ(T) variation followed by 1% Al2O3-water nanofluid with μ(T) variation, 2.5% Al2O3-water nanofluid with constant property solution, and 1% Al2O3-water nanofluid with constant property solution

Experimental Investigation on Engine Performance and Emission Parameters by Using Different Additives in Diesel Engine

The present work is mainly concerned with an experimental investigation to study the diesel engine performance, combustion, noise and emission characteristics using different combination of blends with diesel to solve both the energy and environmental concerns. All relevant information was analyzed to construct a precise summary of background information which included the history of different additives, advantages and limitations, physical and chemicalproperties of additives and their emissions. The emissions from the tailpipe of the engine such as nitrogen oxide (NOx), unburnt hydrocarbon (HC), carbon dioxide (CO2) and carbon monoxide (CO) were recorded and explained. The experiments were conducted using different loads to collect the emission data. The outcome of this study reveals that no single blend can satisfy all of the requirements. Achievement of one aspect can only be achieved at the expense of other. As far as emissions are concerned two major contributors of NOx and HC are found to be inversely proportional. To reduce one aspect, a compromise of other is required. Results were classified into two major categories i.e., the trends shown by oxygenated and non-oxygenated blended fuel

Experimental study on compressive strength of cement-CNT composite paste

35-38The role of carbon nanotubes (CNTs) on the compressive strength characteristics of hydrated Portland IS 1489 cement paste has been studied. Standard specimens (40 mm × 40 mm × 160 mm) as per IS: 516-2004 were prepared by mixing 0.1% CNTs by weight to cement for determining the compressive strength of composites. The specimens were tested after 7, 14, 28 and 35 days of curing. Results show an increase in compressive strengths in Cement–CNTs composites having CNT content of 0.1% by weight of cement. The increase in compressive strengths with both techniques; mixture of CNTs with cement in powder form and mixture of CNTs with cement in hydrated form were 8.5% and 22%, respectively by holding the specimen for 28 days of curing. Increase in curing time by 7 days from 28 to 35 days did not bring any appreciable increase in compressive strength because of the complete absorption of all the ingredients into the mixture due to saturation

Numerical investigation on performance and emission characteristics of a diesel engine fired with methanol blended diesel fuel / Gurkamal Nain Singh...[et al.]

The effects of methanol and oleic acid blended diesel fuel on the performance and emissions of the diesel engine are evaluated numerically by commercial software Diesel-RK to simulate a single cylinder, naturally aspirated, direct injection, four-stroke diesel engine. The present study also resolves the problem of the immiscibility of methanol in diesel fuel, as to avoid immiscible nature an optimum percentage of oleic acid and n-butanol is added to make blends stable. The methanol blended diesel fuels are 7%, 12%, and 17% methanol in volume basis (D85M7NB1O7, D75M12NB1O12, and D65M17NB1O17). A drastic reduction in NOx emission is observed due to low combustion temperature however the PM emissions increases which can be controlled by using exhaust after-treatment techniques. The results indicate that: the brake specific fuel consumption increases and brake thermal efficiency decreases with an increase of methanol, oleic acid and n-butanol contents in the blended fuel whereas maximum heat release rate increases and exhaust temperature decreases

Optimization of LPG Diffusion Flame Synthesis of CNT Structures using Statistical Design of Experiments (SDOE)

A statistical designed experimental approach was followed to investigate the various diffusion flame conditions for the synthesis of carbon nanotubed structures utilizing domestic Liquefied petroleum gas (IS – 4576) as the fuel carbon source. LPG flow rate, Oxygen flow rate, Height above burner (HAB) and Exposure time have been identified to generate different flame conditions based on varying One factor at a time (OFAT) approach. Two–level ‘full factorial’ design model in “Minitab12” software has been used for design of experiments. The 16 samples of soot with different flame conditions were collected on the surface of stainless steel plate. The output parameters i.e. weight of soot and substrate surface temperature were analyzed by Analysis of variance (ANOVA) to ensure that the experimentation is following the physics of the diffusion flame.Transmission electron microscope (TEM) images showed the growth of well aligned single walled carbon nanotubed structures with high aspect ratio as 220nm – 650nm diameter and 534nm – 1803nm length. In the present studythe parametric range for producing the single walled carbon–nanotubed structures through LPG diffusion flame have been found for optimization

Design and development of the front wheel hub for All-Terrain Vehicle (ATV) / Himanshu Verma...[et al.]

An all-terrain vehicle (ATV) is a single seat, open cockpit, and open wheel off-road vehicle in which the engine is located behind the driver. The present paper discusses the important aspects of designing and development of the front wheel hub of ATV. This study discusses the design of the front wheel hub while considering that it should be of light weight and high strength. This paper discusses the material selection for the hub from the two different types of material. This study includes the improvement in the design of the hub with the help of various analyses of the hub. The hub is analyzed in the various loading conditions to obtain the appropriate factor of safety with the help of a static structural module of ANSYS software