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Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering
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Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Marine Science and Engineering".

Deadline for manuscript submissions: closed (30 April 2022) | Viewed by 44776

Special Issue Editor

Dr. Eunkyung Lee

E-Mail Website
Guest Editor
Department of Ocean Advanced Materials Convergence Engineering, Korea Maritime and Ocean University, Busan 49112, Korea
Interests: material characterization; mechanical properties; microstructure
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

This Special Issue on the topic of “Sustainable and Smart Marine Engineering” aims to share the latest information and knowledge on marine engineering and technology. This Special Issue will play a key role in developing eco-friendly LNG and hydrogen engine vessels, LNG bunkering vessels, autonomous operating ships, drillships for natural resources, navy vessels, and submarines.

Some of the technical areas to be covered in this Special Issue are: 

  • Thermal engineering;
  • Power generation and mechanics;
  • Materials and manufacturing engineering;
  • Fluid engineering;
  • Control and instrumentation engineering;
  • Electrical, electronic, and communication engineering;
  • Technology for disaster prevention of ships and maritime safety;
  • Other topics in the marine-related field (maritime education, maritime regulations and laws, etc.).

Dr. Eunkyung Lee
Guest Editor

Manuscript Submission Information

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Published Papers (15 papers)

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Research

15 pages, 5727 KiB  
Article
Study on Reducing Towing Drag by Varying the Shape and Arrangement of Floats and Gears
by Jung-Mo Jung, Yoshiki Matsushita and Seonghun Kim
Appl. Sci. 2022, 12(15), 7606; https://doi.org/10.3390/app12157606 - 28 Jul 2022
Cited by 4 | Viewed by 1685
Abstract
Many studies have been conducted with the aim of reducing fuel consumption by the fishing industry. We examined whether drag can be reduced by changing the arrangement of gears without requiring the development of new parts for the conventional float and ground gear. [...] Read more.
Many studies have been conducted with the aim of reducing fuel consumption by the fishing industry. We examined whether drag can be reduced by changing the arrangement of gears without requiring the development of new parts for the conventional float and ground gear. Ten differently shaped floats and ground gears were measured in a water flume tank. The float and ground gear were fixed to a steel rod to measure fluid drag according to attack angle, using a multi-component load cell. To estimate the frictional drag of ground gear on the seabed, five types of large ground gear were towed on flat land while changing attack angle using the load cell to measure tension. The fluid drag of the float and ground gear was highest at an attack angle of 60°, regardless of shape, size, and flow velocity. The resistance coefficients of the float and ground gear varied depending on the attack angle and tended to be lower at small attack angles. The frictional drag of the ground gear was greater when the axis of rotation had a small attack angle in the towing direction compared to other attack angles. We then investigated a method for designing bottom-towed gear that reduces drag while maintaining the size, buoyancy, and sinking force of conventional fishing gear parts. This gear design showed 1.2% drag reduction and an estimated 0.8% improvement in fuel efficiency per haul. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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25 pages, 4883 KiB  
Article
Thermal Evaluation of a Novel Integrated System Based on Solid Oxide Fuel Cells and Combined Heat and Power Production Using Ammonia as Fuel
by Phan Anh Duong, Borim Ryu, Jinwon Jung and Hokeun Kang
Appl. Sci. 2022, 12(12), 6287; https://doi.org/10.3390/app12126287 - 20 Jun 2022
Cited by 20 | Viewed by 3509
Abstract
A novel integrated system based on solid oxide fuel cells (SOFCs), a gas turbine (GT), the steam Rankine cycle (SRC), the Kalina cycle (KC), and the organic Rankine cycle (ORC) is proposed to achieve cascade energy utilization. Mathematical models are introduced and system [...] Read more.
A novel integrated system based on solid oxide fuel cells (SOFCs), a gas turbine (GT), the steam Rankine cycle (SRC), the Kalina cycle (KC), and the organic Rankine cycle (ORC) is proposed to achieve cascade energy utilization. Mathematical models are introduced and system performance is analyzed using energy and exergy methods. The first and second laws of thermodynamics are used to analyze the system thermodynamically. In addition, exergy destruction and losses of the various integrated subsystems are calculated. The energy and exergy efficiencies of the multigeneration system are estimated to be 60.4% and 57.3%, respectively. In addition, the hot water produced during the waste heat recovery process may also be used for accommodating seafarers on ships. Sequential optimization is developed to optimize the operating conditions of the integrated system to achieve the required power output. A comprehensive parametric study is conducted to investigate the effect of varying the current densities of the fuel cell and working fluid of the ORC on the overall performance of the combined system and subsystems. The working performance of five working fluids for the ORC as candidates—R134a, R600, R601, R152a, and R124—is compared. R152a, which provides 71.23 kW of power output, and energy and exergy efficiencies of 22.49% and 42.76%, respectively, is selected as the best thermodynamic performance for the ORC. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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16 pages, 5296 KiB  
Article
A Path Planning Method for Ship Collision Avoidance Considering Spatial–Temporal Interaction Effects
by Shuwu Wang, Ming Huang, Chen Chen, Jie Sun and Feng Ma
Appl. Sci. 2022, 12(10), 5036; https://doi.org/10.3390/app12105036 - 16 May 2022
Cited by 4 | Viewed by 2170
Abstract
Efficient and reliable path planning is crucial for smart ships when avoiding collisions with static and dynamic obstacles in complex marine environments. This research proposes a novel path planning method based on the fast marching method to specifically assist with safe navigation for [...] Read more.
Efficient and reliable path planning is crucial for smart ships when avoiding collisions with static and dynamic obstacles in complex marine environments. This research proposes a novel path planning method based on the fast marching method to specifically assist with safe navigation for autonomous ships. At the very beginning, a unified representation is specially produced to describe the path planning space based on the parametric fast marching speed function. In addition, the spatial–temporal interaction effects of dynamic obstacles are considered and integrated into the construction of planning space. Subsequently, a path optimization strategy is put forward based on the trajectory prediction of dynamic objects. Particularly, the effectiveness of the method has been validated and evaluated through a number of simulations, which proves that such a method is practical in narrow and crowded waterways. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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13 pages, 2720 KiB  
Article
Analysis of Hydrogen Filling of 175 Liter Tank for Large-Sized Hydrogen Vehicle
by Moo-Sun Kim, Hong-Kyu Jeon, Kang-Won Lee, Joon-Hyoung Ryu and Sung-Woong Choi
Appl. Sci. 2022, 12(10), 4856; https://doi.org/10.3390/app12104856 - 11 May 2022
Cited by 11 | Viewed by 2399
Abstract
Due to the low density of hydrogen gas under ambient temperature and atmospheric pressure conditions, the high-pressure gaseous hydrogen storage method is widely employed. With high-pressure characteristics of hydrogen storage, rigorous safety precautions are required, such as filling of compressed gas in a [...] Read more.
Due to the low density of hydrogen gas under ambient temperature and atmospheric pressure conditions, the high-pressure gaseous hydrogen storage method is widely employed. With high-pressure characteristics of hydrogen storage, rigorous safety precautions are required, such as filling of compressed gas in a hydrogen tank to achieve reliable operational solutions. Especially for the large-sized tanks (above 150 L), safety operation of hydrogen storage should be considered. In the present study, the compressed hydrogen gas behavior in a large hydrogen tank of 175 L is investigated for its filling. To validate the numerical approach used in this study, numerical models for the adaptation of the gas and turbulence models are examined. Numerical parametric studies on hydrogen filling for the large hydrogen tank of 175 L are conducted to estimate the hydrogen gas behavior in the hydrogen tank under various conditions of state of charge of pressure and ambient temperature. From the parametric studies, the relationship between the initial SOC pressure condition and the maximum temperature rise of hydrogen gas was shown. That is, the maximum temperature rise increases as the ambient temperature decreases, and the rise increases as the SOC decreases. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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15 pages, 69259 KiB  
Article
Numerical Analysis of the Effects of Ship Motion on Hydrogen Release and Dispersion in an Enclosed Area
by Byeol Kim and Kwang-Il Hwang
Appl. Sci. 2022, 12(3), 1259; https://doi.org/10.3390/app12031259 - 25 Jan 2022
Cited by 7 | Viewed by 3360
Abstract
Hydrogen is an alternative to conventional heavy marine fuel oil following the initial strategy of the International Maritime Organization (IMO) for reducing greenhouse gas emissions. Although hydrogen energy has many advantages (zero-emission, high efficiency, and low noise), it has considerable fire and explosion [...] Read more.
Hydrogen is an alternative to conventional heavy marine fuel oil following the initial strategy of the International Maritime Organization (IMO) for reducing greenhouse gas emissions. Although hydrogen energy has many advantages (zero-emission, high efficiency, and low noise), it has considerable fire and explosion risks due to its thermal and chemical characteristics (wide flammable concentration range and low ignition energy). Thus, safety is a key concern related to the use of hydrogen. Whereas most previous studies focused on the terrestrial environment, we aim to analyze the effects of the ship’s motion on hydrogen dispersion (using commercial FLUENT code) in an enclosed area. When compared to the steady state, our results revealed that hydrogen reached specific sensors in 63% and 52% less time depending on vessel motion type and direction. Since ships carry and use a large amount of hydrogen as a power source, the risk of hydrogen leakage from collision or damage necessitates studying the correspondence between leakage, diffusion, and motion characteristics of the ship to position the sensor correctly. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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14 pages, 3874 KiB  
Article
Analysis of Bluetooth RSSI for Proximity Detection of Ship Passengers
by Qianfeng Lin and Jooyoung Son
Appl. Sci. 2022, 12(1), 517; https://doi.org/10.3390/app12010517 - 5 Jan 2022
Cited by 9 | Viewed by 3064
Abstract
Concern about the health of people who traveled onboard was raised during the COVID-19 outbreak on the Diamond Princess cruise ship. The ship’s narrow space offers an environment conducive to the virus’s spread. Close contact isolation remains one of the most critical current [...] Read more.
Concern about the health of people who traveled onboard was raised during the COVID-19 outbreak on the Diamond Princess cruise ship. The ship’s narrow space offers an environment conducive to the virus’s spread. Close contact isolation remains one of the most critical current measures to stop the virus’s rapid spread. Contacts can be identified efficiently by detecting intelligent devices nearby. The smartphone’s Bluetooth RSSI signal is essential data for proximity detection. This paper analyzes Bluetooth RSSI signals available to the public and compares RSSI signals in two distinct poses: standing and sitting. These features can improve accuracy and provide an essential basis for creating algorithms for proximity detection. This allows for improved accuracy in identifying close contacts and can help ships sustainably manage persons onboard in the post-epidemic era. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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11 pages, 7088 KiB  
Article
Fundamental Study on Underwater Cutting of 50 mm-Thick Stainless Steel Plates Using a Fiber Laser for Nuclear Decommissioning
by Kwan Kim, Moo-Keun Song, Su-Jin Lee, Dongsig Shin, Jeong Suh and Jong-Do Kim
Appl. Sci. 2022, 12(1), 495; https://doi.org/10.3390/app12010495 - 5 Jan 2022
Cited by 12 | Viewed by 3146
Abstract
With nuclear power plants worldwide approaching their design lifespans, plans for decommissioning nuclear power plants are increasing, and interest in decommissioning technology is growing. Laser cutting, which is suitable for high-speed cutting in underwater environments and is amenable to remote control and automation, [...] Read more.
With nuclear power plants worldwide approaching their design lifespans, plans for decommissioning nuclear power plants are increasing, and interest in decommissioning technology is growing. Laser cutting, which is suitable for high-speed cutting in underwater environments and is amenable to remote control and automation, has attracted considerable interest. In this study, the effects of laser cutting were analyzed with respect to relevant parameters to achieve high-quality underwater laser cutting for the decommissioning of nuclear power plants. The kerf width, drag line, and roughness of the specimens during the high-power laser cutting of 50 mm-thick stainless steel in an underwater environment were analyzed based on key parameters (focal position, laser power, and cutting speed) to determine the conditions for satisfactory cutting surface quality. The results indicated that underwater laser cutting with a speed of up to 130 mm/min was possible at a focal position of 30 mm and a laser power of 9 kW; however, the best-quality cutting surface was obtained at a cutting speed of 30 mm/min. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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12 pages, 4768 KiB  
Article
De-Powdering Effect of Foundry Sand for Cement Casting
by Seungyeop Chun, Geumyeon Lee, Sujin Kim, Bora Jeong, Jeehoon Shin, Inkyung Cho, Hongdae Kim, Heesoo Lee and Taewook Kim
Appl. Sci. 2022, 12(1), 266; https://doi.org/10.3390/app12010266 - 28 Dec 2021
Viewed by 1857
Abstract
With the development of the powder bed 3D printing process, sand casting can be performed with methods that are more advanced than the traditional ones, thus enabling new research on applied materials. When sand is 3D-printed with cement as a binder, its casting [...] Read more.
With the development of the powder bed 3D printing process, sand casting can be performed with methods that are more advanced than the traditional ones, thus enabling new research on applied materials. When sand is 3D-printed with cement as a binder, its casting performance is improved and sufficient thermal stability of conventional organic and inorganic binders is ensured. In this study, to ensure high resolution and strength in a physical and simple mixture of cement and sand, the compatibility for casting was confirmed using submicron-level cement with ingredients and sizes similar to commercial sand, which is uniformly controlled at 4 µm, instead of conventional sand. To enable quick 3D printing, calcium aluminate cement, which has quick binding properties, was used for high-temperature casting. The strength up to 6 h after hydration was compared to determine the curing rate of silica, mullite, and alumina sand containing cement components. By investigating the change in strength due to heat treatment and comparing the adhesion drop test results after powder bed formation, the material containing silica sand was determined as the most suitable for powder layer 3D printing for application to the mold. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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14 pages, 1908 KiB  
Article
Multi-Task Deep Learning Model with an Attention Mechanism for Ship Accident Sentence Prediction
by Ho-Min Park and Jae-Hoon Kim
Appl. Sci. 2022, 12(1), 233; https://doi.org/10.3390/app12010233 - 27 Dec 2021
Cited by 3 | Viewed by 2557
Abstract
The number of ship accidents occurring in the Korean ocean has been steadily increasing year by year. The Korea Maritime Safety Tribunal (KMST) has published verdicts to ensure that the relevant personnel can share judgment on these accidents. As of 2020, there have [...] Read more.
The number of ship accidents occurring in the Korean ocean has been steadily increasing year by year. The Korea Maritime Safety Tribunal (KMST) has published verdicts to ensure that the relevant personnel can share judgment on these accidents. As of 2020, there have been 3156 ship accidents; thus, it is difficult for the relevant personnel to study these various accidents by only reading the verdicts. Therefore, in this study, we propose a multi-task deep learning model with an attention mechanism for predicting the sentencing of ship accidents. The tasks are accident types, applied articles, and the sentencing of ship accidents. The proposed model was tested under verdicts published by the KMST between 2010 and 2019. Through experiments, we show that the proposed model can improve the performance of sentence prediction and can assist the relevant personnel to study these accidents. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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14 pages, 5115 KiB  
Article
Study on the Variable Speed Diesel Generator and Effects on Structure Vibration Behavior in the DC Grid
by Quang Dao Vuong, Jongsu Kim, Jae-Hyuk Choi, Jae-ung Lee, Ji-woong Lee, Hyeonmin Jeon, Jung-Ho Noh, Sung Hwan Yoon and Won-Ju Lee
Appl. Sci. 2021, 11(24), 12049; https://doi.org/10.3390/app112412049 - 17 Dec 2021
Cited by 3 | Viewed by 3581
Abstract
Global warming and air pollutants are in general major worldwide concerns including for the marine shipping industry. Equipped with new technologies, the onboard DC grid has proven several advantages, including up to 27% reduction in specific fuel consumption with reduced emissions. That can [...] Read more.
Global warming and air pollutants are in general major worldwide concerns including for the marine shipping industry. Equipped with new technologies, the onboard DC grid has proven several advantages, including up to 27% reduction in specific fuel consumption with reduced emissions. That can be achieved by installing an optimized variable speed diesel generator. The engine speed is adjusted according to the required power, which allows to always keep the best efficiency of the combustion process. However, it also exposes some changes in the behavior of the structure vibrations. Measurements on an experimental variable speed diesel generator show that vibration increases when trying to slow down the engine for the same load. This behavior is closely related to the resonance in low rev range that usually occurs with general gensets. In other words, we can conclude that the DC grid’s variable speed generator may be beneficial for fuel efficiency, but not for mechanical life and safety. Several measures had been given, of which the alternation of the natural frequency is presented as an economical and efficient solution. The ultimate goal is to maintain operational safety while respecting reduced fuel consumption. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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8 pages, 2537 KiB  
Article
S and P Dual-Doped Carbon Nanospheres as Anode Material for High Rate Performance Sodium-Ion Batteries
by Hyeon-Su Yang, Si-Wan Kim, Kwang-Ho Kim, Sung-Hwan Yoon, Min-Jae Ha and Jun Kang
Appl. Sci. 2021, 11(24), 12007; https://doi.org/10.3390/app112412007 - 16 Dec 2021
Cited by 9 | Viewed by 2900
Abstract
The heteroatom doping of carbon materials can significantly improve the electrochemical performance of sodium-ion batteries. However, conventional doping techniques involve more than two steps, making them unsuitable for scale-up. In this study, an S and P co-doped carbon material is synthesized using a [...] Read more.
The heteroatom doping of carbon materials can significantly improve the electrochemical performance of sodium-ion batteries. However, conventional doping techniques involve more than two steps, making them unsuitable for scale-up. In this study, an S and P co-doped carbon material is synthesized using a simple, one-step plasma-in-liquid process. The synthesized material consists of abundant macropores, which can improve the electrochemical properties of sodium-ion batteries. When the synthesized anode material is applied to a sodium-ion half-cell, the cell exhibits a remarkable cycling life of 3000 cycles at a high current density of 10 A g−1, with a high reversible capacity over 125 mAh g−1. These results indicate that S and P co-doped carbon materials are promising candidates as anodes for sodium-ion batteries, and the plasma-in-liquid process is an effective strategy for heteroatom co-doping. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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9 pages, 2474 KiB  
Article
Enhancing SERS Intensity by Coupling PSPR and LSPR in a Crater Structure with Ag Nanowires
by Jae-Hoon Ryu, Ha Young Lee, Jeong-Yeon Lee, Han-Sol Kim, Sung-Hyun Kim, Hyung Soo Ahn, Dong Han Ha and Sam Nyung Yi
Appl. Sci. 2021, 11(24), 11855; https://doi.org/10.3390/app112411855 - 13 Dec 2021
Cited by 13 | Viewed by 2953
Abstract
The sensitive characteristics of surface-enhanced Raman scattering (SERS) can be applied to various fields, and this has been of interest to many researchers. Propagating surface plasmon resonance (PSPR) was initially utilized but, recently, it has been studied coupled with localized surface plasmon resonance [...] Read more.
The sensitive characteristics of surface-enhanced Raman scattering (SERS) can be applied to various fields, and this has been of interest to many researchers. Propagating surface plasmon resonance (PSPR) was initially utilized but, recently, it has been studied coupled with localized surface plasmon resonance that occurs in metal nanostructures. In this study, a new type of metal microstructure, named crater, was used for generating PSPR and Ag nanowires (AgNWs) for the generation of LSPR. A crater structure was fabricated on a GaAs (100) wafer using the wet chemical etching method. Then, a metal film was deposited inside the crater, and AgNWs were uniformly coated inside using the spray coating method. Metal films were used to enhance the electromagnetic field when coupled with AgNWs to obtain a high SERS intensity. The SERS intensity measured inside the crater structure with deposited AgNWs was up to 17.4 times higher than that of the flat structure with a deposited Ag film. These results suggest a new method for enhancing the SERS phenomenon, and it is expected that a larger SERS intensity can be obtained by fine-tuning the crater size and diameter and the length of the AgNWs. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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12 pages, 10901 KiB  
Article
A Study on the Application of Laser Cleaning on the Weld of the Gas Fuel Supply Pipe for DF Engine
by Ji-Eon Kim, Pyung-Su Kim, Jong-Myoung Lee, Han-Seop Choe and Jong-Do Kim
Appl. Sci. 2021, 11(24), 11832; https://doi.org/10.3390/app112411832 - 13 Dec 2021
Cited by 2 | Viewed by 2402
Abstract
While producing gas fuel supply pipes for duel fuel (DF) engines, a welding process is essential. Accordingly, specimen management before and after welding is crucial to obtain highly reliable weldments. In this study, we developed an environmentally friendly laser cleaning technology to address [...] Read more.
While producing gas fuel supply pipes for duel fuel (DF) engines, a welding process is essential. Accordingly, specimen management before and after welding is crucial to obtain highly reliable weldments. In this study, we developed an environmentally friendly laser cleaning technology to address a toxic work environment and environmental pollution problems caused by chemical cleaning technology utilized in post-welding treatment of gas fuel supply for DF engines. An experiment was conducted by implementing surface laser cleaning of the butt and fillet weldment specimens according to process parameters. Conditions of process parameters were identified for facilitating laser cleaning and used in prototype production. The prototypes were processed through laser and chemical cleaning, and the quality of the end products was compared. The results indicated that the proposed method satisfactorily cleans the prototype surface without generating a toxic work environment and environmental pollution problems. Moreover, the roughness of approximately 5 μm was achieved on the laser cleaned surface. This is considered to be able to increase the adhesion of the paint compared to the smooth chemical cleaned surface during the painting for anticorrosion of the product. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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11 pages, 4407 KiB  
Article
Effects of Post-Treatment to Improve the Surface Quality of 3D Printing Cement Mold Casting
by Seung-Yeop Chun, Geumyeon Lee, Su-jin Kim, Bora Jeong, Jeehoon Shin, Inkyung Cho, Hong-Dae Kim, Heesoo Lee and Taewook Kim
Appl. Sci. 2021, 11(24), 11824; https://doi.org/10.3390/app112411824 - 13 Dec 2021
Cited by 4 | Viewed by 2660
Abstract
Powder bed 3D printing can be applied to sandcasting mold manufacturing to ensure high quality and economy through process innovation. In this study, refractory alumina cement was used as an aqueous binder to ensure high-temperature thermal stability to minimize the addition of organic [...] Read more.
Powder bed 3D printing can be applied to sandcasting mold manufacturing to ensure high quality and economy through process innovation. In this study, refractory alumina cement was used as an aqueous binder to ensure high-temperature thermal stability to minimize the addition of organic matter to reduce gas generation. In addition, spherical silica sand, the study material, was selected to a size of 30 µm to improve the casting mold resolution. To improve the surface quality through the post-treatment process, we confirmed the change in the surface roughness of the mold depending on the surface treatment of colloidal silica and the presence or absence of heat treatment, and finally made the mold through actual casting. Changes in the surface roughness and flowability of the cast body after mold post-treatment were confirmed. For aluminum castings, the shrinkage rate and surface roughness were confirmed in a box-shaped mold via gravity casting, and the flowability of the molten metal in the mold was confirmed in a hand-shaped mold. There was a change in the roughness and porosity of the mold, owing to the post-treatment, and the influence of the surface roughness and flowability of the cast body during actual casting was confirmed. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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16 pages, 9626 KiB  
Article
Profile Design of the Grooved Die and Rolling Force Prediction in the Cold Pilger Rolling Process
by Sang-Kon Lee and Kyung-Hun Lee
Appl. Sci. 2021, 11(23), 11265; https://doi.org/10.3390/app112311265 - 27 Nov 2021
Cited by 4 | Viewed by 4801
Abstract
The objective of this study was to design the die groove profile and predict the rolling force produced when employing the variable curvature rolls and mandrel for manufacturing seamless pipes using the cold pilger rolling process. The parameters of the key process design [...] Read more.
The objective of this study was to design the die groove profile and predict the rolling force produced when employing the variable curvature rolls and mandrel for manufacturing seamless pipes using the cold pilger rolling process. The parameters of the key process design were the diameter of the initial tube and final product, as well as the feed amount, reduction area, principal deformation zone, and roller radius. The rolling forces during the pilger rolling process were theoretically calculated to enable their prediction, and the characteristics of the cold pilger rolling process were identified. The calculated values were in close agreement with the experimental data. The die groove design is important in the prediction process because the dimensional accuracy of the tubes and the life of the dies are highly dependent on this design. The presented design method can be successfully applied to fulfill this objective. The tube shape and adequate tolerance can be attained by using the proposed design method. The mechanical properties of the pipe are evaluated by calculating the Q factor. Full article
(This article belongs to the Special Issue Advanced Marine Engineering and Technology: Sustainable and Smart Marine Engineering)
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