Raldi A. Koestoer

Zero method heat flux sensor

Abstract For measuring the heat flux on a cylindrical or plane wall, a heat flux sensor was especially designed for surfaces with small dimensions (5 cm × 5 cm). Chromel—constantan thermocouples with a diameter of 50 μm and a teledeltos paper were used to make a prototype. This sensor is based on compensation measuring methods so it needs no calibration. Two experimentals results obtained are comparable to within 8% and 5% to those obtained by the direct method. Using microelectronic technology, the experimental sensor was investigated further to identify possible fields of application, and to reduce its size.

The Utilization of Heat Pipe on Cold Surface of Thermoelectric with Low-Temperature Waste Heat

Thermoelectric (TE) modules are a thermo-element device that can harness the heat and convert it into electrical energy. As an electrical generator system, TE has several advantages i.e not noisy, easy maintenance, relatively small, lightweight and environmentally friendly because it does not produce pollution. In this paper, the research about the performance of TE modules that used for electric generator has been done. TE modules utilize low temperature waste-heat from a solar cell that simulated with a combination of a bulb and a collector plate. TE modules which tested are single and double modules, in which for double modules, connectivity Thermal-Series was used. Parameters of performance such as output power generated are determined by measuring the temperatures difference and the voltages difference at the test module as well as using several equations. The results show that the distance of heat source and load applied will greatly affect the performance of thermoelectric generator (TEG) modules. The results showed that the number of modules and loading will greatly affect the performance of TEG modules. The use of heat pipes generate a far greater power 4-6 times on the single TE Module (0.84 mW) than without heat pipe (0.14 mW), and a double TE modules that uses heat pipe will became 4 times larger (1.48mW) than without heat pipe (0.37mW).

POTENSI PEMBANGKIT DAYA TERMOELEKTRIK UNTUK KENDARAAN HIBRID

Potency of Thermoelectric Generator for Hybrid Vehicle. Thermoelectric Generator (TEG) has been known as electricity generation for many years. If the temperature difference occurred between two difference semi conductor materials, the current will flow in the material and produced difference voltage. This principle is known as Seebeck effect that is the opposite of Peltier effect Thermoelectric Cooling (TEC). This research was conducted to test the potential of electric source from twelve peltier modules. Then, these thermoelectric generators were applied in hybrid car by using waste heat from the combustion engine. The experiment has been conducted with variations of peltier module arrangements (series and parallels) and heater as heat source for the thermoelectric generator, with variations of heater voltage input (110V and 220V) applied. The experimental result showed that twelve of peltier modules arranged in series and heater voltage of 220V generated power output of 8.11 Watts with average temperature difference of 42.82°C. This result shows that TEG has a bright prospect as alternative electric source.

Two-phase Frictional Pressure Drop of Propane with Prediction Methods of Viscosity and Density in 500 μm Diameter Tube

The experimental study of frictional pressure drop of two-phase flow with propane on the microchannel has been done. The aim of the present research is to characterize pressure drop of evaporative propane in microchannel with 500 μm diameter and 0.5 m length. The experimental apparatus used heating process in the test section with closed loop process system. Variable of research are mass flux of 360 to 915 kg/m2s and vapor quality of 0 to unity. The homogeneous and separated model used to determine the two-phase flow frictional pressure drop. Some existing correlations of two-phase flow viscosity and density used to predict frictional pressure drop, including parameter C that used non-dimensional parameter of two-phase viscosity number Nμtp which developed as a function of two-phase viscosity and density. The comparison of prediction frictional pressure drop showed that the Hibiki, Xuejiao and Pamitran correlation from separated model.

Influence of temperature on conversion of plastics waste (polystyrene) to liquid oil using pyrolysis process

Plastic waste has been a problem in waste treatment.The growth of plastic waste is increasing especially in Jakarta and needs more serious attention in waste processing. To convert polystyrene to be liquid much heat energy is needed. In this research, pyrolysis is used as the method to process polystyrene to be aliquid product. The objective of this research is to obtain the characteristics of the heating process, and the properties of the liquid product. This liquid can be used as a fuel. Fixed-bed reactor with SUS 316L as the base material was constructed to decompose the polystyrene using an electric heater, which was controlled using Digital PID controller. Power sensor was mounted in the electrical circuit to monitor the power that entered to the heater and recorded using data acquisition. The reaction temperature was varied from 350 °C – 550 °C. No sweep gas injected into the system. The vapor flows naturally based on their partial pressure. The temperature of cooling water was varied into two conditions, water ambient temperature, and cold water. To condense pyrolysis vapor to be liquid oil, the double-pipe condenser was constructed. The thermocouples were installed at many points of the system to monitor temperature change in the system. The maximum liquid yield was obtained at reaction temperature 500 °C with cooling water temperature at 16.59°C.The operating temperature Below 500 °C will produce more wax, and above 500 °C will produce much gas. The liquid can be applied as fuel with heating value 43.83 mJ/kg, density 0.89 g/ml and0.78 cSt of kinematic viscosity.