DESIGN SCENARIO AND ANALYSIS FOR PRELIMINARY SPECIFICATION OF STEAM GENERATOR IN THE PELUIT-40

The helical steam generator is connected to an HTGR-type nuclear reactor called PeLUIt-40 for steam production. Steam is used to generate electricity and hydrogen. A once-through helical tube bundle was employed because of its ability to endure mechanical stress due to thermal expansion, high resistance to flow-induced vibrations, and better thermal performance compared to a straight tube one. To produce the targeted steam, a design analysis of the once-through helical steam generator needs to be conducted. A quick evaluation method was used to predict the preliminary specifications required for steam production. Simple thermodynamic calculations combined with empirical heat transfer coefficients covering convective and boiling processes at constant pressure were used to carry out the analysis. Two scenarios were conducted to evaluate the design choice based on the previous design of RDE-10

Peningkatan Produktivitas Pengusaha Kerupuk Mlarat melalui Perancangan Mesin Pengulen dan Pemotong Adonan

Kerupuk Mlarat is one of the traditional snacks of Cirebon, a regency in West Java province, Indonesia. This snack is mostly produced by the small medium enterprises (SMEs) through conventional, old-style procedures. That is why, although this snack has abundant potentials, the improvement is still minimum. Most SMEs employ human-powered tools, especially in the process of dough kneading and shaping. Besides the not yet optimum process, the food hygiene of also becomes an issue. In order to optimize the production and maintain product hygiene, a human empowerment program is conducted to provide on of the SMEs with the Kerupuk Mlarat dough kneading and shaping machine. The machine capacity is 20 kilograms and was proven effective to knead, shape, and cut the dough within an hour, a lot less duration compared to the conventional procedures. This machine is expected to efficiently improve the Kerupuk Mlarat SMEs productivity as well as hygiene

Spark ignition engine modeling for in-cylinder pressure and temperature prediction using simulink

Mathematical model for four-stroke gasoline engines based on a cylinder-by-cylinder engine modeling method that incorporates physical formulas such as engine geometry and empirical formulas such as combustion duration are applied in this study. In-cylinder pressure and temperature can be calculated for gasoline four-cycle engine. Modeling is done by treating each step in the cylinder as a volume control, solving the conservation equations of energy with submodules for combustion, heat transfer and dynamic analysis. Calculations in cycles are performed at each crank angle, so that the correct angle of ignition, variations in velocity, amount of intake mass and fuel burning speed can be predicted. Adjustment for the combustion parameter such as burn duration and form factor of the Wiebe function to increase the model accuracy was performed. It is shown that the optimization of the Wiebe function parameters able to improve the sum squared error of the engine pressure estimation by 58.17% compared to the result from generalized parameter functions, and the parameter of form factor and burn duration are influential by around twice of (1.86 and 2.55 times, respectively) the efficiency factor