Parametric Study of an Organic Rankine Cycle Using Different Fluids

This work is an energy study of an organic Rankine cycle (ORC) for the recovery of thermal energy by comparing three organic fluids. This cycle is considered to be a promising cycle for the conversion of heat into mechanical energy suitable for low temperature heat sources; it uses more volatile organic fluids than water, which generally has high molecular weights, thus allowing operating pressures at temperatures lower than those of the traditional Rankine cycle. A thermodynamic model was developed using the Engineering Equation Solver (EES) software to determine its performance using different working fluids (toluene, R245fa and R123) under the same operating conditions, taking into account the effect of certain operating parameters and the selection of organic fluids on cycle performance. The results obtained show that the toluene organic fluid has the best thermal efficiency of the cycle compared to the other fluids; 14.38% for toluene, 13.68% for R123 and 13.19 for R245fa

Prandtl Number Effects on the Entropy Generation During the Transient Mixed Convection in a Square Cavity Heated from Below

This numerical study considers the mixed convection, heat transfer and the entropy generation within a square cavity partially heated from below with moving cooled vertical sidewalls. All the other horizontal sides of the cavity are assumed adiabatic. The governing equations, in stream function–vorticity form, are discretized and solved using the finite difference method. Numerical simulations are carried out, by varying the Richardson number, to show the impact of the Prandtl number on the thermal, flow fields, and more particularly on the entropy generation. Three working fluid, generally used in practice, namely mercury (Pr = 0.0251), air (Pr = 0.7296) and water (Pr = 6.263) are investigated and compared. Predicted streamlines, isotherms, entropy generation, as well as average Nusselt numbers are presented. The obtained results reveal that the impact of the Prandtl number is relatively significant both on the heat transfer performance and on the entropy generation. The average Nusselt number increase with increasing Prandtl number. Its value varies thereabouts from 3.7 to 3.8 for mercury, from 5.5 to 13 for air and, from 12.5 to 15 for water. In addition, it is found that the total average entropy generation is significantly higher in the case of mercury (Pr«1) and water (Pr»1) than in the case of air (Pr~1). Its value varies approximately from 700 to 1100 W/m3 K for mercury, from 200 to 500 W/m3 K for water and, from 0.03 to 5 W/m3 K for air

Designing and analyzing park sensor system for efficient and sustainable car park area management

Many problems have been seen in cities because of increasing vehicle density. One of these problems is vehicle density in parking lots. People look for empty parking areas and they spend too much time. While people look for empty parking areas, CO2 (carbon dioxide) emission and energy consumption increase due to density in parking lots. We worked to solve these problems by doing Magnetic Car Park Sensor. Magnetic Car Park Sensor is the system which detects cars in car parks. After cars detected with the system, the system sends information to center server and we can see information data in the system interface. The system helps people to find empty parking lots. As people find empty car park areas fastly, energy consumption and CO2 emission are decreased significantly

Penentuan Hubungan Antara Defleksi Lateral dan Radial Poros Baja Pada Berbagai Jenis Tumpuan Secara Teoritik

Defleksi lateral dan radial memiliki persamaan tersendiri karena selain memiliki arah defleksi yang berbeda juga memiliki turunan persamaan yang berbeda. Oleh karena itu perhitungan untuk kedua jenis defleksi ini masih dilakukan secara terpisah. Penelitian ini bertujuan untuk mengetahui hubungan antara defleksi radial dan lateral pada jenis tumpuan jepit-bebas, jepit-roll, dan jepit-jepit secara teoritik; sebuah hubungan yang memungkinkan penentuan defleksi lateral dan radial dilakukan secara bersamaan. Metode penentuan defleksi radial dan lateral serta hubungannya dilakukan berdasarkan kajian pada berbagai literatur. Hasil penelitan menunjukan bahwa adanya hubungan yang diperoleh antara defleksi radial dan lateral berupa beberapa persamaan. Konstanta Kotten ini memiliki nilai sebesar 1,93 untuk jenis tumpuan jepit-bebas, 35,39 untuk tumpuan jepit-roll, dan 61,93 untuk jenis tumpuan jepit-jepit.

An Energy Investigation of An Organic Rankine Cycle Utilizing Three Organic Fluids

This study presents an energy study of an Organic Rankine Cycle ORC by comparing three organic fluids. The latter is considered as a promising cycle for the conversion of heat into mechanical energy adapted to low-temperature heat sources; it uses more volatile organic fluids than water, which generally has high molecular weights, thus allowing operating pressures at temperatures lower than those of the traditional Rankine cycle. This study devoted to the energy analysis of the ORC cycle, taking into account the effect of the operating temperatures and the choice of the organic fluid on the cycle performance. The utilized three fluids were Toluene, R245fa and R123. The results obtained show that the Toluene organic fluid has the best energy efficiency of the cycle with 7.45%

Autoignition behavior and emission of biodiesel from palm oil, waste cooking oil, tyre pyrolysis oil, algae and jatropha

Alternative fuels have recently been researched on diesel substitution, with the target of reducing dependence on petroleum-based fuel in addition to reducing environmental pollution. Thanks to its regenerability and ability to absorb emissions, the opted biofuel tends to be advantageous. The present study explored the autoignition behaviour, in particular the ignition delay and process of combustion that strongly influence exhaust emissions. The analysis used biodiesel blends obtained from palm oil, waste cooking oil, algae, jatropha and tyre pyrolysis oil at various blending ratio from 2% to 20%. These blending ratios were achieved independently through a specific blending technique with pure diesel at different volumetric concentrations. The ignition delay was assessed by means of a rapid compression machine (RCM) under variant injection pressure at an elevated ambient temperature of the reaction chamber. This study discovered significant differences in ignition delays and combustion efficiency when different biodiesel blends were operated under higher injection pressures and higher ambient temperatures. The shortest ignition delay of biodiesel blend fuels is achieved at low blending concentrations, implying that lower concentrations of biodiesel encapsulate a lower fuels viscosity, preceded by excellent spray atomization, premixing, and ignitability. In addition to these implications, the shortest ignition delay was undoubtedly influenced by higher injection pressure and higher temperature conditions in which the expansion of the fuel’s molecular bound to the C–H bonding deteriorates and bonding energy dissociates. Emissions are lower than pure diesel with an increased concentration of blends; waste cooking oil-biodiesel blends experienced positive effects on the CO, HC and nitrogen oxides (NOx) via variant injection pressure; while significant improvements in HC were noticed for most fuels, corresponding to the elevated ambient temperature circumstances

The effect of 48V mild hybrid technology on fuel consumption of a passenger car by using simulation cycle

The ASEAN's legislation has become more regulatory towards electric vehicles for automotive manufacturers to ensure the environment is preserved better for future generations. The ASEAN roadmap 2025 requirement in optimizing a conventional vehicle's fuel consumption is implemented with hybrid technology in targeting the automotive industry worldwide to achieve energy-efficient vehicles. This research aims to develop a vehicle model via 1D simulation cycle and implement the 48V mild hybrid to lower vehicle fuel consumption considering perspective in drive cycles data. The vehicle model used in this research is a D-segment vehicle powered by a 1.8L TGDI engine. The base model will be created using a GT Suite software where data is compared and analyzed with actual vehicle measurement. There will be two models produced; with and without Belt-Alternator-Starter (BAS) system. They will be further investigated for their functions based on NEDC and RDC drive cycles for fuel consumption. However, implementing the add-on technology from this simulation improved overall vehicle fuel consumption by 7.7% in NEDC and 1.7% in RDC. The results obtained for the optimization of the vehicle have shown difference by the results of each engine characteristics such as engine fuel flow rate, speed, torque, the BAS functions, and state of charge. The research proposes its findings to understand the practical usage of 48V mild hybrid system in fuel reduction and provide reliable proof to use as a reference for initiative studies