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This paper introduces the design, construction, and static testing of a solid rocket motor. The design was based on the solid rocket motor design methodology (SRM). The rocket motor included the igniter system, the combustion chamber, the solid propellant, and the nozzle. The internal diameter of the combustion chamber and the total length of the rocket motor were 27,67 mm and 230 mm, respectively. The rocket motor nozzle was of the convergent-divergent Laval type. The propellant was based on the mixture of potassium nitrate (KNO3) (oxidant) and high purity sugar (or sucrose: C12H22O11) (fuel), whose synthesis was achieved through a thermal fusion process (150-170 °C for 20-25 min). The performance of the rocket motor was evaluated using a static combustion test; resulting in a maximum thrust force (load) of 227 N, a total impulse of 98,69 Ns and a specific impulse of 65,8 s, thus allowing its classification as a class G rocket motor. The results obtained are considered of great importance in the development and characterization of solid rocket motors, necessary to promote the experimental rocketry in Colombia. [ABSTRACT FROM AUTHOR]

Internal combustion engines are complex machines that constitute an object of design, and in which diverse processes and variables encounter. In the industrial field, the design of a new engine begins with the conception of a wellestablished solution with consideration on the experience of the designers. To perform the structural design of an engine, it is needed to determine the forces and moments acting on its components, derived from the processes along the cycles of work, with observation of the variations of the pressures and the temperatures in the cylinder and of the forces and moments of inertia in the components of the mechanisms and the structure. It is the purpose of the present paper to introduce the development of a series of procedures to obtain the preliminary dimensions of the main components of an engine (power mechanism, engine block and cylinder head dimensions), applying the machine design fundamentals and the thermodynamic and dynamic characterization of a generic engine of combustion, using the minimum information (power, torque, engine speed, and conditions of exploitation). To systematize the engine preliminary design, a spreadsheet based on Microsoft Excel was developed. To use this spreadsheet, the user must specify composition of the fuel, the type of ignition, and the wished characteristics of the engine. The outputs of the spreadsheet are the global stoichiometric balance of fuel-air chemical reactions, the heat release rate, the indicator diagram, the forces and moments acting on the main components of the crank-train mechanism, such a valuable information required to conduct the dimensioning of the engine components making use of the fundamentals of strength of materials. [ABSTRACT FROM AUTHOR]

Gasoline internal combustion engines have known issues related to thermal efficiency and high emission of polluting gases. On the other hand, there are chemical and electrical processes that have provided sources of clean energy from water. Electrolysis allows the production of hydrogen and oxygen gas by means of an electrochemical process, from which HHO is obtained. The molecular characteristics of HHO allow the reduction of toxic gases to the environment and the saving of hydrocarbon fuels in internal combustion engines. In this paper, we investigate the potential benefits of HHO mixtures as an additive to fossil fuels, in particular, commercial gasoline. We describe the design of a system with an electrolytic cell and evaluate the performance of a 110 cm3 engine in terms of brake specific fuel consumption, brake power, brake torque and gas emissions. [ABSTRACT FROM AUTHOR]