• Transactions of the Korean Society of Automotive Engineers
• /
• v.7 no.7
• /
• pp.86-93
• /
• 1999

Turbocharger has been used to increase the performance of diesel engine, especially ship engine , for years. Recently, the turbocharger is being adopted not only for an agricultural engine but also for an automobile engine. To improve the performance of diesel engine , the problem of the reduction of A/F ratio in high speed should be solved. Turbocharger is well known for its cost effectiveness, reliability and duration . In this study, an experiment was conducted to verify simulation program . The results for natural aspiration engine and turbocharged engine were compared. In order to estimate the characteristics of exhaust gas, D-13 mode was selected. Power, torque and BSFC of turbocharged engine were increased than those of natural aspiration engine by about 48%, 46% and 5%, respectively . The components in exhaust gas except NOx from turbocharger engine were less than the amount set up for 2000-year regulation.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.10 no.5
• /
• pp.79-84
• /
• 2011

Air pollutants from a small marine diesel engine are increasing and the IMO(International Marine Organization) regulation asked for its reduction. In this study, NOx reduction technologies such as improvement of various cooling systems are applied to the small marine diesel engine. The various cooling systems are a intercooler, a heat exchanger for engine coolant, and an exhaust manifold by water cooling. These systems are tested on an engine dynamometer and a exhaust gas analyzer by a marine diesel engine test regulation. Test results are shows that the small marine engine are satisfied the IMO NOx regulations; Tire II.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.22 no.9
• /
• pp.837-844
• /
• 2012

We considered an approach in terms of materials for improvement of insulation performance of vehicle rubber hoses. Ethylene propylene rubber(EPDM) for heater hoses in cooling system and acrylic rubber(AR) for intercooler hose in intake system were chosen for mixing for the vibration and noise performance. We modified EPDM and AR through changing compound of base polymer, reinforcement fillers and additives. Dynamic mechanical analysis(DMA) was used to measure viscoelastic properties such as shear modulus and loss factor($tan{\delta}$). Vehicle acceleration test was also conducted to observe indoor changes in insulation performance of hoses.

• Proceedings of the SAREK Conference
• /
• 2009.06a
• /
• pp.533-538
• /
• 2009

The present study has been conducted to an analysis of two stage refrigeration cycle with alternative refrigerant R410A. In the analysis, single stage cycle (R22 and R410A) compared to COP changing with supercooling degree. Secondly, two stage refrigeration cycle is investigated to the existence of intercooler or supercooler. At results, supercooler contributes to the increase of cooling capacity and the decrease of COP.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.27 no.2
• /
• pp.81-86
• /
• 2015

Performance of freezing and refrigeration systems in supermarket, which utilized $CO_2$ as a refrigerant, was investigated by using the Pack Calculation II. The configuration of simulated systems was basic parallel refrigeration system, cascade system, and two-stage system. The $CO_2$ cascade system showed higher COP than basic parallel R404A system by 13% for MT and 62% for LT, respectively. Among the $CO_2$ cascade systems, R717(MT)-$CO_2$(LT) showed the highest performance. Open-type intercooler method showed higher performance than liquid injection for the two-stage $CO_2$ systems.

• Journal of Aerospace System Engineering
• /
• v.17 no.5
• /
• pp.58-62
• /
• 2023

In this work, the structural integrity was investigated of the structural design results of internal components for the aircraft engine. The radiator and intercooler were combined with the internal components of the engine. Therefore, the safety of the radiator and intercooler was investigated during flight conditions. The structural integrity was evaluated through structural analysis, using the finite element analysis method. The acceleration load for structural design and analysis was considered. The structural safety evaluation found the structural design results to be valid.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.36 no.1
• /
• pp.17-24
• /
• 2012

There has been little study on the performance characteristics of the effective heat pump systems in the cooling mode using the two-stage compression cycles have hardly performed. In this study, the performance of the two-stage compression $CO_2$ cycle with an FI (flash intercooler) and the FGB (flash gas bypass) was investigated by using a theoretical method. The performance analysis was carried out with aby varyingiation (the indoor temperature, outdoor temperature, and 1st- and 2nd-stage EEV openings. As of a result, the coefficients of performance (COPs) of the Bbasic, FI, and FGB cycles were decreased by 28.5%, 22.1%, and 24.5%, respectively, for various outdoor temperature conditions. In addition to, the performance variation of the two-stage compression cycle was smaller than that of the single-stage compression cycle. The performance of the FI and FGB cycles was improved by 13.5%, and 6.9%, respectively, when the 1st-stage EEV opening was increased from 32% to 48%, and by 0.9%, and 2.6%, respectively, when the 1st- andthe 2nd-stage EEV opening was increased from 32% to 48%, andwas increased from 42% to 58%, respectively. The FI cycle showed anthe most improved performance for any given operating conditions.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.2
• /
• pp.153-161
• /
• 2009

Three-dimensional finite-element methods(FEM) have been used to analyze the thermal stress of an exhaust gas recirculation(EGR) cooler due to thermal and pressure load. Since efficiency and capability of the heat exchanger are mainly dependent on net heat transferring area of the EGR cooler system, the tube inside the system has a numerous dimples on the surface. Thus for finite element analysis, firstly the dimple-typed tube is modeled as a plain element without the dimple, and then the equivalent thermal conductivities and elastic modulus are calculated. This work describes the numerical homogenization procedure of the dimple-typed tube and verifies the equivalent material properties by comparison of a single unit and the actual full model. Finally, the homogenization scheme presented in this study can be efficiently applied to finite element analyses for the thermal stress and deformation behavior of the EGR cooler system with the dimple-typed tube.

• Journal of Power System Engineering
• /
• v.15 no.6
• /
• pp.11-15
• /
• 2011

This study investigated the symptoms of the a reduction in output while driving on the road, or increasing of fumer out exhaust gas on inclined road while working air-conditioner in summer. Notice how the experiment in 2010, the Ministry of Environment(Chapter No. 2010-46), and how the vehicle emissions inspection was carried out. 2500cc Diesel cars used in the study were used and compare to output of engine, exhaust gas, inhalation temperature measurement Inhalation of cold air has not been supplied to all agencies when comparing the results when cold air intake temperature of the supply air-conditioning switch range control from 1 to 4, the temperature drops $98^{\circ}C$ to $78^{\circ}C$. At the momentum of switch level 4, output from 63ps to 66ps after the connection has increased 9.6 percent, the highest concentration of exhaust emissions were reduced by 42.8%. This research can contribute in part to the reduction of exhaust directly supply into the cooling air intake line, doing the output of diesel cars in the summer. In addition, construction equipment and machinery that are currently being used excluding the engine's intercooler cooling of the supply line via a separate output in the summer and help reduce exhaust emissions is expected.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.11a
• /
• pp.223-224
• /
• 2008