Low Vacuum Research Articles

Performance Evaluation of an Evacuated Flat-Plate Collector System for Domestic Hot Water Applications

AbstractRapid population growth and increasing energy demand in developing countries are the key drivers behind rising concerns such as energy poverty and environmental degradation. Harnessing solar energy can help the developing countries inch closer to sustainable economic growth. This article presents the performance analysis of a solar water heating system based on an evacuated flat-plate collector (EFPC). EFPCs offer higher optical performance and lower thermal losses in comparison with conventional solar collectors. In this study, a multiparametric analysis provides the guidelines for the design and optimization of a novel low vacuum EFPC system under ambient conditions, for domestic hot water (DHW) applications. A small-scale solar thermal collector system based on a low vacuum (17.5–20 kPa) EFPC of a total area of 4.0 m2 is designed and installed. The system is coupled with a storage tank composed of the helical copper coil configuration inside the tank, which is used as a heat exchanger from a primary loop to a secondary loop. A series of real-time experiments are performed under ambient conditions from December to April. The thermal efficiency of the EFPCs reaches a maximum value of 73.2%, with the glycol–water mixture as a heat transfer fluid at an inlet temperature of 31.2 °C, when the ambient temperature is 15.3 °C, average irradiance is 679.2 Wm−2, and vacuum pressure is 20 kPa. For this duration, the exergy efficiency reaches a peak value of 16%. This EFPC system provides 100 liters of hot water at 57–69 °C per day for DHW consumption when the average ambient temperature is 24 °C. The overall results highlight the potential of EFPCs for hot water applications. Furthermore, an efficiently optimized EFPC system can also be used for space heating during the winter season.

Development and Characterization of Low Temperature Wafer-Level Vacuum Packaging Using Cu-Sn Bonding and Nanomultilayer Getter.

Most microsensors are composed of devices and covers. Due to the complicated structure of the cover and various other requirements, it difficult to use wafer-level packaging with such microsensors. In particular, for monolithic microsensors combined with read-out ICs, the available process margins are further reduced due to the thermal and mechanical effects applied to IC wafers during the packaging process. This research proposes a low-temperature, wafer-level vacuum packaging technology based on Cu-Sn bonding and nano-multilayer getter materials for use with microbolometers. In Cu-Sn bonding, the Cu/Cu3Sn/Cu microstructure required to ensure reliability can be obtained by optimizing the bonding temperature, pressure, and time. The Zr-Ti-Ru based nanomultilayer getter coating inside the cap wafer with high step height has been improved by self-aligned shadow masking. The device pad, composed of bonded wafer, was opened by wafer grinding, and the thermoelectrical properties were evaluated at the wafer-level. The bonding strength and vacuum level were characterized by a shear test and thermoelectrical test using microbolometer test pixels. The vacuum level of the packaged samples showed very narrow distribution near 50 mTorr. This wafer-level packaging platform could be very useful for sensor development whereby high reliability and excellent mechanical/optical performance are both required. Due to its reliability and the low material cost and bonding temperature, this wafer-based packaging approach is suitable for commercial applications.

Insights into peptide profiling of sturgeon myofibrillar proteins with low temperature vacuum heating.

Protein oxidation during food processing causes changes in the balance of protein-molecular interactions and protein-water interactions, ultimately leading to protein denaturation, which results in the loss of a range of functional properties. Therefore, how to control the oxidative modification of proteins during processing has been the focus of research. In the present study, the intrinsic fluorescence value of the myofibrillar proteins (MP) decreased and the surface hydrophobicity value increased, indicating that the heat treatment caused a significant change in the conformation of the MP. With an increase in heating temperature, protein carbonyl content increased, total sulfhydryl content decreased, and protein secondary structure changed from α-helix to β-sheet, indicating that protein oxidation and aggregation occurred. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that heat treatment can lead to the degradation of proteins, especially myosin heavy chain, although actin had a certain thermal stability. In total, 733 proteins were identified by proteomics, and the protein oxidation caused by low temperature vacuum heating (LTVH) was determined to be mild oxidation dominated by malondialdehyde and 4-hydroxynonenal by oxidation site division. The present study has revealed the effect of LTVH treatment on the protein oxidation modification behavior of sturgeon meat, and explored the effect mechanism of LTVH treatment on the processing quality of sturgeon meat from the perspective of protein oxidation. The results may provide a theoretical basis for the precise processing of aquatic products. © 2023 Society of Chemical Industry.

Engineering Solution-Processed Non-Crystalline Solid Electrolytes for Li Metal Batteries.

Non-crystalline Li-ion solid electrolytes (SEs), such as lithium phosphorus oxynitride, can uniquely enable high-rate solid-state battery operation over thousands of cycles in thin film form. However, they are typically produced by expensive and low throughput vacuum deposition, limiting their wide application and study. Here, we report non-crystalline SEs of composition Li-Al-P-O (LAPO) with ionic conductivities > 10-7 S cm-1 at room temperature made by spin coating from aqueous solutions and subsequent annealing in air. Homogenous, dense, flat layers can be synthesized with submicrometer thickness at temperatures as low as 230 °C. Control of the composition is shown to significantly affect the ionic conductivity, with increased Li and decreased P content being optimal, while higher annealing temperatures result in decreased ionic conductivity. Activation energy analysis reveals a Li-ion hopping barrier of ≈0.4 eV. Additionally, these SEs exhibit low room temperature electronic conductivity (< 10-11 S cm-1) and a moderate Young's modulus of ≈54 GPa, which may be beneficial in preventing Li dendrite formation. In contact with Li metal, LAPO is found to form a stable but high impedance passivation layer comprised of Al metal, Li-P, and Li-O species. These findings should be of value when engineering non-crystalline SEs for Li-metal batteries with high energy and power densities.

Synthesis and Characterization of Citric Acid-Modified Iron Oxide Nanoparticles Prepared with Electrohydraulic Discharge Treatment.

Chemical co-precipitation from ferrous and ferric salts at a 1:1.9 stoichiometric ratio in NH4OH base with ultrasonication (sonolysis) in a low vacuum environment has been used for obtaining colloidal suspensions of Fe3O4 nanoparticles coated with citric acid. Before coating, the nanoparticles were processed by electrohydraulic discharges with a high discharge current (several tens of amperes) in a water medium using a pulsed direct current. Magnetite nanoparticles were obtained with an average crystallite diameter D = 25-28 nm as obtained by XRD and particle sizes of 25 nm as measured by small-angle X-ray scattering. Magnetometry showed that all samples were superparamagnetic. The saturation magnetization for the citric acid covered samples after electrohydraulic processing showed higher value (58 emu/g) than for the directly coated samples (50 emu/g). Ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy showed the presence and binding of citric acid to the magnetite surface by chemisorption of carboxylate ions. Hydrodynamic sizes obtained from DLS and zeta potentials were 93 and 115 nm, -26 and -32 mV for the citric acid covered nanoparticles and 226 nm and 21 mV for the bare nanoparticles, respectively. The hydraulic discharge treatment resulted in a higher citric acid coverage and better particle dispersion. The developed method can be used in nanoparticle synthesis for biomedical applications.

ХИМИЧЕСКОЕ ОСАЖДЕНИЕ ИЗ ГАЗОВОЙ ФАЗЫ ПИРОУГЛЕРОДНЫХ ПОКРЫТИЙ НА ПОРОШКАХ В ПСЕВДООЖИЖЕННОМ СЛОЕ. I. АППАРАТУРА, ПСЕВДООЖИЖЕНИЕ

A laboratory setup for chemical vapor deposition (CVD) at reduced pressure on powder of medium particle size in a fluidized bed (reactor load of 50 g of substrate) was described. Calculations of critical points for the onset of fluidization and entrainment of particles for various gases (Ar, C3H8, C4H10) at a temperature of 20–1000 °C under low vacuum (pressure of 5 kPa) were performed. Model experiments were carried out on the fluidization of corundum powder (granularity of ~300 μm) in an argon flow, as well as in the propane-butane mixture in the absence of CVD. The dependences of the hydrodynamic mode of fluidization on the nature of fluidizing gas, temperature and pressure were analyzed, which make it possible to plan the process of coating deposition itself.

Manufacturing of near-net-shape composite parts using Tailored Fiber Placement preforms

This paper demonstrates the feasibility of manufacturing a light and low cost near-net-shape vertebra from Tailored Fiber Placement (TFP) preforms. The TFP preforms were produced flat and sewn together at the ends by a classic sewing process. Low pressure Vacuum Assisted Resin Transfer Molding (VARTM) was used for the consolidation and impregnation of the preforms. The molding strategy was oriented towards the use of silicone conformers to ensure a compaction that well fits the preform despite its imperfections. The resulting part required a light finishing. The mass was reduced by 40% and the manufacturing cost by 76% compared to the original part.

Design, fabrication and characterization of MoS2self-lubricating pure MoS2Coatings for space applications using PVD magnetron sputtering

Tribological components cost just a fraction of the whole spacecraft, but they often lead to failures that partially or completely disrupt the spacecraft. Mechanical components used in space applications have to withstand extreme and severe environmental conditions such as very high or very low cryogenic temperatures, high vacuum, corrosive elements and radiation. MoS2 is the most widely used lubricating material in space applications. It possesses a lamellar structure with strong covalent bonds within layers and simultaneously weak van der Wall’s interlayer bonds, resulting in easy shearing of the crystals in the direction parallel to the basal planes, hence acting as a good solid lubricant.In this research, a thin film nano scale coating of MoS2 was deposited on steel using Physical Vapour Deposition (PVD). The PVD technique used was the RF magnetron sputtering process. Material characterization was performed using X-Ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Raman spectroscopy. According to the results, the developed MoS2 nano coatings have a polycrystalline structure with basal planes that are oriented perpendicular to the substrate surface.

Physical processes in the Pirani type low vacuum sensor

Auger electron spectroscopy and thermoresistive methods are used to study the physical processes leading to gas cooling of heated molybdenum filaments in a wide temperature range of 350-1300 K and pressures of 760-10-3 Torr, corresponding to the operating range of a Pirani-type vacuum sensor. Nitrogen was used as the gas. It is shown that nitrogen atoms chemisorbed on the surface do not contribute to gas cooling, which occurs only due to physisorbed N2 molecules. In the intermediate vacuum region of 10-3-1 Torr, the heater is cooled due to the equilibrium between the flux of incident and thermally desorbed molecules, which is well described by the Hertz--Knudsen formula and first-order desorption with an activation energy of ~0.55 eV. On the contrary, at high pressures close to atmospheric, this cooling occurs due to the thermal desorption of gas molecules from an almost filled monolayer, which reduces its relative efficiency by many orders of magnitude. Keywords: vacuum, adsorption, Pirani sensor, molybdenum, thermal desorption, nitrogen.

Toward White Light Random Lasing Emission Based on Strained Nano Polygermanium Doped with Tin via Metal-Induced Crystallization (MIC)

Solubility of Sn in Ge network gives it a preference for photonic applications, because of the direct transition in GeSn alloy. Here, we employed the metal-induced crystallization (MIC) process of amorphous Ge and Si via Sn as a novel mechanism to incorporate Sn inside Ge and Si networks. (Al/Si/Sn/Ge/Sn) and (Al/Ge/Sn/Ge/Sn) multilayers are deposited by thermal vacuum evaporation on different substrates. The devices are annealed under low vacuum at 500 °C to incorporate the oxygen for band-gap tuning. The structure of Ge-doped nanocrystals is investigated. The direct transition and band-gap values have been estimated using diffuse reflectance spectroscopy and photoluminescence (PL) measurements. PL indicated that the junctions have emissions from visible to NIR regions that make them promising as optically pumped white-light sources as well as waveguide applications, and the impact of the base substrate on enhancing the emission has been investigated via PL measurements. Electroluminescence measurements show that the prepared heterostructures on fluorine-doped tin oxide (FTO) substrate have sharp random lasing spikes over the range of PL samples spectra as the sample can lase randomly by light scattering through the Ge-doped nanocrystalline materials. The charge carrier lifetime measurements show high lifetime for the prepared sample. These give them the chance to be a candidate for white-light random laser diode applications.

Determination of heat transfer mechanisms during vacuum drying of solid-moist and liquid-viscous materials

Most drying methods combine convective, conductive and radiation heat transfer processes. The share of each type of heat transfer may vary depending on the type and mode of drying, type of product, etc. In this study, the problem of determining the heat transfer mechanism of vacuum drying of solid-moist and liquid-viscous materials is solved. The objects of the study are Jerusalem artichoke tubers, camel and mare milk. The numerical values of the heat transfer components are found experimentally and their shares in the total heat flux are determined. During vacuum drying of Jerusalem artichoke at a medium pressure of 4 kPa and a temperature of 55 °C (with a layer height of 0.01 and 0.02 m), the convective component predominates (58.55 and 67.65 %). The share of thermal conduction (18.96 and 29.39 %) and radiation (13.39 and 12.05 %) is much lower. The mechanism of thermal conduction begins to prevail with an increase in the height of the material layer (0.03 and 0.04 m). The convective component is also dominant for vacuum drying of milk: at medium pressures of 6÷10 kPa and a temperature of 40 °C, its value for mare milk reaches 78.21 %, for camel milk – 73.33 %. The second most important is the share of radiation (19.45 and 22.58 %). Conductive heat transfer has the minimum indicators (5.66 and 6.17 %). The large values of the share of thermal conduction during drying of Jerusalem artichoke compared to milk are explained by the fact that heat transfer occurs inside the tubers due to conduction, and inside milk – due to convection. Insignificant shares of radiation are explained by low and medium vacuum values in the chamber. In the studied range, heat and mass transfer occurs due to molecular diffusion and convection. The results obtained can be used to formulate criterion heat transfer equations, in engineering calculations, and optimization of the vacuum dryer operation.

Evaluation of time exposure of different irrigation agents on radicular dentin erosion

Aim: The amount of root dentin erosion caused by Ethylene diamine tetraacetic acid (EDTA), Glycolic acid (GA), and Etidronic acid (HEDP) solutions applied with sonic activation (SA) for 1 and 3 minutes during the final irrigation was evaluated in this in vitro study. Methods: Using 5 ml of 2.5% NaOCl irrigation solution in each sample, 70 mandibular premolars were enlarged with the Reciproc R25 rotary instrument system. The samples were randomly divided according to the final irrigation protocol into 6 experimental groups (n:10) and 1 control group (n:10): Group 1 (17% EDTA – 1 min SA), Group 2 (17% EDTA – 3 min SA), Group 3 (10% GA – 1 min SA), Group 4 (10% GA – 3 min SA), Group 5 (18% HEDP – 1 min SA), Group 1 (18% HEDP – 3 min SA) and Group 7 (Negative control group-distilled water, 1 min SA). The teeth were divided into two parts longitudinally after the final irrigation protocol. A low vacuum scanning electron microscope (SEM) was used to image the samples’ coronal, middle, and apical root areas at x2000 magnification. Samples were evaluated using a triple-scoring system. Results: Data were analyzed by Shapiro Wilk, Kruskal Wallis H, Mann-Whitney U, and Dunn’s tests. There was no statistically significant difference between EDTA, GA, and HEDP in both periods (p &gt; 0.05). Conclusion: We saw similar amounts of erosion in dentin in 1 and 3 minutes of chelation applications for all chelators. Considering the smear removal efficiency of chelators, there is no harm in increasing the time in terms of erosion. There is a need for studies on the clinical applicability of chelation with a different duration time. How to cite this article: Okumuş ÖF, Kaya S, Adıgüzel Ö, Yeniçeri Özata M. Evaluation of time exposure of different irrigation agents on radicular dentin erosion. J Med Dent Invest 2022;3:e221170. https://doi.org/10.5577/jomdi.e221170 Linguistic revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English. Checked for plagiarism: Yes

Effects of Growth Period and Storage Methods on Primary Metabolite Contents and Antioxidant Activities of Morus alba L. Leaf.

(1) Background: Mulberry leaves have been widely consumed due to their richness in bioactive substances and high antioxidant activity. The choice of storage method to ensure the quality of mulberry leaves is a challenge in the supply process. (2) Methods: The differences in primary metabolites of freeze-dried mulberry leaf powder after 30 days of storage under different storage conditions (i.e., vacuum or non-vacuum, 4 °C or room temperature) were investigated. (3) Results: A low temperature and vacuum had better preservation effects on the types and activity of the primary metabolites of mulberry leaves, with vacuum preservation being the best. However, the types of primary metabolites in mulberry leaves were significantly reduced after non-vacuum storage at room temperature compared to those with other storage methods. Among the metabolites detected, including dehydroascorbic acid, various phenolic acids, amino acids, lipids, and carbohydrates showed a significant decrease in their contents of more than 40%, and there was a significant increase in the contents of various compounds of the muconic acid biosynthetic pathway compared to those in other storage methods. Moreover, the antioxidant activity of mulberry leaves stored at room temperature under non-vacuum conditions was also significantly reduced. (4) Conclusions: Vacuum storage is the most ideal storage method for preserving mulberry leaves.

Investigation of Structure and Optical Properties for Copper Oxide Thin Films on Plastic Substrate by Helicon Plasma DC Magnetron Sputtering Technique

As we move towards a decarbonized society, transparent solar cells have recently become an important means of increasing power generation in familiar locations. Copper oxide has been attracting attention as a candidate material for the production of transparent solar cells. In order to further expand the range of applications, it is believed that it will be necessary to develop flexible, transparent plastic substrates. For the purpose of optical applications, copper oxide thin films with CuO, Cu2O, or both phases were fabricated on highly transparent plastics such as poly-methyl methacrylate (PMMA) and polycarbonate (PC), as well as on a glass substrate as a comparable sample. The helicon plasma DC magnetron sputtering method was used to fabricate thin films at a low deposition temperature due to the low heat resistance of plastic substrates. In addition, the helicon plasma DC magnetron sputtering method is capable of depositing films at low vacuum pressure, which enables the preparation of thin films with high crystallinity. The structure, surface shape, and optical properties of fabricated films were investigated using X-ray diffraction (XRD), a laser microscope, and a UV-Vis spectrophotometer, respectively. In this study, the formation of copper oxide thin films on plastic substrates at low temperatures has been verified, as have the crystal structure and optical properties, which is considered a rare study in this field.

Influence of advanced wound matrices on observed vacuum pressure during simulated negative pressure wound therapy

Biomaterials and negative pressure wound therapy (NPWT) are treatment modalities regularly used together to accelerate soft-tissue regeneration. This study evaluated the impact of the design and composition of commercially available collagen-based matrices on the observed vacuum pressure delivered under NPWT using a custom test apparatus. Specifically, testing compared the effect of the commercial products; ovine forestomach matrix (OFM), collagen/oxidized regenerated cellulose (collagen/ORC) and a collagen-based dressing (CWD) on the observed vacuum pressure. OFM resulted in an ∼50% reduction in the observed target vacuum pressure at 75 mmHg and 125 mmHg, however, this effect was mitigated to a ∼0% reduction when fenestrations were introduced into the matrix. Both collagen/ORC and CWD reduced the observed vacuum pressure at 125 mmHg (∼15% and ∼50%, respectively), and this was more dramatic when a lower vacuum pressure of 75 mmHg was delivered (∼20% and ∼75%, respectively). The reduced performance of the reconstituted collagen products is thought to result from the gelling properties of these products that may cause occlusion of the delivered vacuum to the wound bed. These findings highlight the importance of in vitro testing to establish the impact of adjunctive therapies on NPWT, where effective delivery of vacuum pressure is paramount to the efficacy of this therapy.

Investigation of vacuum-integrated switchable polymer dispersed liquid crystal glazing for smart window application for less energy-hungry building

The presence of more than one transparency and controllable intermediate transmission between ON and OFF states make the switchable smart glazing more attractive for less energy-hungry building integration than a static transparent window. However, to enable this switchable glazing for cold climatic buildings, overall heat transfer through the glazing needs to be reduced. In this work, the thermal and optical performance of integrated polymer dispersed liquid crystal and low heat loss transparent vacuum glazing was investigated using indoor characterisation. Two systems were developed where PDLC glazing was sandwiched between a vacuum and one acrylic sheet (Vacuum-PDLCA) and vacuum and glass (Vacuum-PDLCG). The employment of acrylic sheets reduced 21% of the overall weight of the system which made it suitable for retrofit building integration. Use of acrylic reduced 35% of solar transmission of PDLC ON state compared to the use of glass. Overall heat transfer coefficient (U-value) or thermal transmittance was below 1.1 W/m2K for all Vacuum -PDLCG and Vacuum-PDLCA ON and OFF states. Solar heat gain coefficient or solar energy transmittance was highest at 0.45 for the Vacuum-PDLCG ON state and lowest at 0.23 for the Vacuum-PDLCA OFF state.

Effect of tea polyphenols on sturgeon myofibrillar protein structure in the in vitro anti-glycation model mediated by low temperature vacuum heating

The binding mechanism between tea polyphenols and sturgeon myofibrillar protein (SMP) in the early stage (0, 2, 4 min), middle stage (6, 10 min) and late stage (15 min) of low temperature vacuum heating (LTVH) in an in vitro anti-glycation model was investigated. The result indicated that the protein cross-linking during LTVH treatment were mainly induced by tea polyphenols. The loss rate of free arginine (Arg) and free lysine (Lys) of SMP at the late stage of LTVH treatment (15 min) was 73.95 % and 83.16 %, respectively. The hydrophobic force and disulfide bond were the main force between tea polyphenols and SMP in the middle and late stage of LTVH treatment. The benzene ring and phenolic hydroxyl group of tea polyphenols can interact with the amino acid residues of SMP, which was exothermic and entropy-increasing. This study provides new insights in the interaction mechanisms between tea polyphenols-protein during heat treatment process.

Microwave Plasma Assisted Aerosol Deposition (μ-PAD) for Ceramic Coating Applications

To improve plasma and chemical resistance on various vacuum components used for semiconductor manufacturing equipment, various ceramic coating techniques have been applied. Among these methods for ceramic coating, the well-known atmospheric plasma spray (APS) is advantageous for providing thick film (100 µm or more) deposition. However, there are problems associated with the phase transition of the coating film and poor film quality due to formation of voids. To solve these problems, the aerosol deposition (AD) method has been developed. This method provides nice ceramic film quality. However, the coating rate is quite slow and has difficulty producing thick films (&gt;30 µm). To overcome these limitations, microwave plasma-assisted aerosol deposition (μ-PAD) is applied at low vacuum conditions without the AD nozzle. This method uses a microwave plasma source during the AD process. After enduring a long-term durability test, as a trial run, μ-PAD has been applied on the actual process site. With the Al2O3 powder, μ-PAD shows a coating rate that is 12 times higher than the AD method. In addition, the formation of a thicker film (96 µm) deposition has been demonstrated. On the other hand, the coating film hardness, porosity, adhesion, and withstand voltage characteristics were confirmed to be less than the AD method.

Flat-end mill machining analysis of processed CrMnFeCoNi high-entropy alloys

ABSTRACT High-entropy alloys are emerging materials and are widely studied at the synthesis and characterization levels. Their machinability study and product realization are still at a nascent stage. Conventional machining operations are necessary to ensure part assembly and surface quality. Hence, end-mill machining is carried out to check the machinability of the most ductile equiatomic and non-equiatomic CrMnFeCoNi high-entropy alloy (HEA) with a green manufacturing concept. Theoretical and experimental analyses examined the effect of percent composition of an element in a high-entropy alloy and machining parameters (spindle speed, depth of cut and feed per tooth) on the cutting forces, chip morphology, machined surface topography, surface micro-hardness and tool wear mechanism. Kistler dynamometer installed in CNC vertical milling machine is used with AlTiN-coated tungsten carbide tool to record the cutting forces and moments. The microstructure anisotropy induced by low vacuum induction melting of varying compositions of elements in high-entropy alloys influenced the machining results. Feed force values were higher for the non-equiatomic HEA sample than for the equiatomic CrMnFeCoNi HEA. SEM and EDS mapping has revealed microhole and microcrack surfaces after machining. Equiatomic CrMnFeCoNi HEA has shown the highest microhardness of 984 Hv than the non-equiatomic HEA sample.

Study on Interior Aerodynamic Noise Characteristics of the High-Speed Maglev Train in the Low Vacuum Tube

As the next-generation high-speed transportation system, the low vacuum tube high-speed maglev system combines the tube with a certain degree of vacuum with the high-speed maglev train, which can realize high-speed operation under low aerodynamic resistance and noise mode. In order to study the interior aerodynamic noise characteristics of the high-speed maglev train in the low vacuum tube, a computational model of the external flow field of the high-speed maglev train in a low vacuum tube was established, and the computational model of the interior aerodynamic noise of the high-speed maglev train was established using the statistical energy analysis method; then the interior aerodynamic noise characteristics of the high-speed maglev train in the low vacuum tube were studied. The research results show that in the low vacuum tube, the distribution of the interior aerodynamic noise of the high-speed maglev train shows the characteristics of large head car and tail car and small middle car, and the aerodynamic noise on the top of the car is smaller than that on the floor. With the increase in frequency, the sound pressure level of the interior aerodynamic noise of the high-speed maglev train has the tendency of increasing first and then decreasing, and the main energy of the interior aerodynamic noise is distributed in the range of 200–1000 Hz. From the perspective of the total sound pressure level of the interior aerodynamic noise, the interior aerodynamic noise of the tail car is the greatest, followed by the head car, and the interior aerodynamic noise of the middle car is the smallest. As the direction of the travel of the maglev train will change, the optimization design of the interior aerodynamic noise of the head and tail cars should be emphasized.