With global warming leading to abnormal weather phenomena and increasing carbon emissions, countries are implementing carbon emission reduction policies. Europe’s Carbon Border Adjustment Mechanism (CBAM) aims to promote environmentally responsible practices while maintaining industrial competitiveness. To avoid potential tariffs in the European market, Korea must vigorously pursue carbon emission reduction. Emphasizing renewable energy adoption is crucial for achieving eco-friendly and sustainable energy production. This study conducted an economic feasibility assessment for constructing small hydroelectric power plants using discharged energy from Goseong Green Power Plant. By evaluating economic viability, decision-makers could assess potential benefits and costs to support effective planning and implementation. Findings of this study could encourage investments in renewable energy projects, fostering a greener and more sustainable energy landscape for the future.
As the Paris Agreement on Climate Change came into effect in 2021, the Korean government set a target of 63.8 GW new renewable power generation until 2030 and announced “The 3020 Implementation Plan of Renewable Energy”, which was a policy to supply more than 95% of the new generation capacity as solar power and wind power. Continuous investment in new renewable energy will be required to reduce the greenhouse effect and to achieve sustainable growth. In particular, offshore wind power is advantageous for the construction of a large-scale power complex. This paper evaluates the suitability of the jacket-type substructure by analyzing the weather environment, marine environment, water depth survey, ground survey, and major equipment selection data. When the new offshore wind power complex is planned, it can be useful for selecting the suitable substructure and determining the turbine capacity to achieve good performance.
The ball screw can be included in steering systems, the brake system, seat moving devices, and transmission systems of vehicles. Performance of the ball screw in these systems plays a key role in delivering agile and accurate power transmission. The purpose of this study is to improve performance by focusing on performance of the ball screw, by applying various conditions based on a design factor in the circulation system. The selected single design factor is to apply the cycloid curve to a circulation area. The circulation part to obtain a cycloid curve with highest performance, can have the smoothest ball flow. In addition, based on results, we intend to reduce failure cost that may be incurred in developing future ball screws for automobiles, and to establish databases that can be applied to developed products by deriving optimal shape.
A gas turbine is the main equipment used in a combined heat and power plant. It generates a high sound pressure noise level. To reduce the noise level, an enclosure is installed around the turbine. The sound insulation performance of the enclosure affects the amount of external noise reduction. In this study, a sound transmission loss analysis is performed using the boundary element method to predict sound insulation performance according to the numbers and shapes of the supporter. Radiated noise analysis is also performed for the main external points of the enclosure using ray-acoustics. The results of these analyses are presented and a design plan is proposed that reduces the sound pressure noise level of the enclosure.
Planetary gear systems have several advantages over traditional gearboxes with parallel axis gear shafts. The planetary gearbox arrangement also creates greater stability due to the even distribution of mass and increased rotational stiffness. However, gears in planetary gear systems occasionally have a short-life due to wear and breakage by repetitive load during operation time. In this study, we evaluated variables of the strength design for each part and conducted structural analysis of seven cases of the planetary gear system. The result of structural analysis was applied to shape optimization method and obtaining the weight lightening designed value. Subsequently, the planetary gear system was performed to ensure the durability of gears during operation time with miner’s rule.
Elongation rolling process is an intermediate process to make the uniform thickness and uniform surface roughness during producing seamless pipes. The thickness and surface roughness of seamless pipes are generally affected by the distance of rolls and guide shoes, the roll shape, and its cross angle. In this study, finite element analysis for shape forming process is based on the analysis model of elongation rolling mill with guide shoes. This paper shows how the cross angle of the roll, the rolling rpm, and the distance of the guide shoe influence on the outer diameter and the thickness of seamless pipes. The rolling rpm did not give much influence on outer diameter.
Evaluation of the structural analysis for a 70/15 ton×105 m LLC (Level Luffing Crane) was conducted with an FEM Tool. Due to a discordance of the modeling and element type, the LLC was progressively analyzed after dividing it into the boom, main structure and rocker. All loads such as slewing, traveling and wind load, etc., that are indicated in the reference standards, were inputted as various severe conditions of the LLC. The deformation, equivalent stress(Von Mises stress), buckling characteristics were evaluated for the LLC structures. The stress concentrated areas over the allowable stress were identified, and reinforcement work was performed with a stiffener.
Oil gear pump is used for the cooling pump system of commercial vehicle. The hydraulic pulsation pressure of oil gear pump is one of the most important reasons for the vibration and noise of the pump. In this study, the several hydraulic factors acting on oil gear motor are analyzed by CFD in operation of cooling system. Forced vibration analysis due to hydraulic pulsation pressure is analyzed by FEA for predicting deformation and equivalent stress.
Transmission is one of the important pars to transmit power from engine to wheels. Mass reduction gears can make the engine power requirement reduce, and can make dynamic performance and fuel efficiency of vehicle improve. Transmission gears are modified for mass reduction without changing their tooth shapes, face widths, and modules by using shape optimization and re-check process. Also structural stability is verified by FEA.
A new tooth profile which is adjusted on the amount of addendum modification factor is proposed for reducing vibration and noise of gears. The transmission error of the new profile can be designed more uniformly than that of the standard involute profile. The basic concepts of tooth profile modification are to reduce the load in contact area and to find the appropriate profile modification factor for operation condition. In this study, gears were estimated to constructive safety of bending strength and contact strength durability by using ROMAX program, and were compared with results by design formula of AGMA standard.
The transmission case has bearing loads. The case should be designed with more stiffness and lightweight under high external loads. In this study, we performed FEA(Finite Element Analysis) for the transmission case and performed topology optimization base on the results of FEA. We performed topology optimization with the control of the shape size which is the results of topology optimization and suggested the shaped of the transmission case of topology optimization.