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In the present investigation, non-edible toxic oils from marine macroalgae Caulerpa racemosa species, richly available in India and composed of high calorific value and high FFA, have been selected as a feedstock for the making of biodiesel. Initially, oil extraction was carried out from the macroalgae biomass with different types of solvent syst ems and extraction steps. The algal oil was extracted with a solvent system consisting of 1 % diethyl ether and 10 % methylene chloride in nhexane using ultrasonic pre-treatment technique. The algal oils were characterized by Gas Chromatography-Mass Spectrometry for composition analysis. The biodiesel was produced by transesterification method. The produced biodiesel was characterized and the conversion was calculated by Fourier-transform infrared spectroscopy (FTIR) analysis and Response Surface Methods. The fuel properties of obtained biodiesel were examined as per the American Standard Test Methods specifications in order to assess the potential of proposed biodiesel as an alternative fuel. Thus, marine macroalgae serve as a potential renewable raw-material for biodiesel production. [ABSTRACT FROM AUTHOR]

Abstract: The Method of search algorithms or optimisation algorithms is one of the most important parameters which will strongly influence the fidelity of the solution during an aerodynamic shape optimisation problem. Nowadays various optimisation methods such as Genetic Algorithm (GA), Simulated Annealing (SA), Particle Swarm Optimisation (PSO) etc., are more widely employed to solve the aerodynamic shape optimisation problems. In addition to the optimisation method, the geometry parameterisation becomes an important factor to be considered during the aerodynamic shape optimisation process. Since the reduction in the number of design parameters is one of the most important requirements for the aerodynamic shape optimisation problem, it becomes important to mathematically describe the airfoil geometry with minimum number of design parameters. The objective of this work is to introduce the knowledge of describing general airfoil geometry using twelve parameters by representing its shape as a polynomial function and coupling this approach with flow solution and optimisation algorithms. It is also demonstrated that the estimation of a suitable optimisation scheme for a given optimisation problem. An aerodynamic shape optimisation problem is formulated for NACA 0012 airfoil and solved using the methods of Particle Swarm Optimisation and Genetic Algorithm for 5.0 deg angle of attack. The results show that the particle swarm optimisation scheme is more effective in finding the optimum solution among the various possible solutions. It is also found that the PSO shows more exploitation characteristics as compared to the GA which is considered to be more effective explorer. [Copyright &y& Elsevier]