Air Inside Research Articles

IMPLEMENTATION OF INTERNET OF THINGS (IOT) TO SIMULATE TEMPERATURE AND HUMIDITY IN NON STERILE MEDICINE PRODUCTION ROOMS USING TEMPERATURE SENSORS (LM 35) AND HUMIDITY SENSORS (DHT 22) BASED ON ARDUINO AND WEB

The development of increasingly sophisticated pharmaceutical industry technology requires researchers to develop technology in the pharmaceutical industry that can help employees carry out their duties. As we know, technology is very helpful in providing job data in industry. Information technology can improve the quality of work in industry. One of them is about monitoring temperature and humidity in the non-sterile drug production room. This temperature and humidity is monitored by the QA ( Quality Assurance )/Quality Assurance department, which is used to see whether the temperature and humidity of the non-sterile drug production room are well conditioned.Based on the existing problems, it is necessary to have an intelligent system that can monitor temperature and humidity precisely and periodically. One of them is creating an Internet of Things (IoT) Implementation tool for Simulating Temperature and Humidity in a Non-Sterile Medicine Production Room Using an Arduino and Web Based Temperature Sensor ( LM35 ) and Humidity Sensor ( DHT 22 ). This tool will periodically detect the temperature and humidity in each non-sterile drug production room. If the temperature exceeds the maximum limit in the non-sterile drug production room, the fan will turn on to release the hot air inside. All the data that has been collected will be processed by the Arduino Uno R3 Microcontroller and will be displayed on the website as an interface . For early detection, a DC Fan appears on the website that rotates if the temperature exceeds the maximum limit. Data transmission uses ESP8266 as a wireless module .

Frost heave model and frost heaving force analysis of permafrost tunnel based on segregated ice

Bi-directional freezing occurs when a tunnel portal passes through an active layer in cold region, or when the tunnel passes through permafrost. The surrounding rock of tunnel portal is frozen by air inside of the tunnel and earth surface. The freezing-thawing cycle of permafrost tunnels is frozen by the permafrost and air inside the tunnel. To investigate the frost heave force on the lining of permafrost tunnels, and verify the layered segregation ice in the surrounding rock of these tunnels, a one-dimensional hydrothermal stress model of bi-directional freezing is established, so as to study the evolution law of segregated ice from the surrounding rock in permafrost tunnels based on the theory of hydro-thermal coupling and segregated ice. After that, based on the mechanical theory, a frost-heave elastic mechanical model including secondary lining, freeze–thaw zone, freezing zone and segregated ice is established. The results show that there is layered segregated ice in the surrounding rock after the lining of permafrost tunnel. The annual difference and the annual average temperature have a great influence on the thickness of segregated ice, while the influence of thermal conductivity is relatively small. The thickness of thawing cycle should be less than 5 m, so that the frost heaving force acting on the lining will not be too large. Good water plugging quality can decrease the thickness of segregated ice. The frost-heaving force acting on the lining increases as the thickness of segregated ice increases. When the thickness of segregated ice is 10 cm, the maximum frost heaving force generated on the lining of single-layer segregated ice is 1.39 times that of non-segregated ice. The frost-heaving force caused by the segregated ice should be considered to guarantee the safety of tunnel structure.

Fast droplets impacting liquid layer under a small angle: a numerical analysis of experimental observations

In presence of a strong wind above a liquid surface, liquid droplets get accelerated and eventually hit the interface with a high speed under a small angle. Experimental studies demonstrate that such droplets may escape the initial crater and either get broken into secondary droplets in the air, or protrude along the interface, leaving behind agitated surface with entrapped bubbles. Here we aim at reproducing the observed phenomena in a numerical model based on Volume of Fluid technique using Basilisk package. On a flat interface, the impacting droplets partially escape the crater and get broken in front of it within the range of impact angles from 15° to 45°, in agreement to the experiments and simple theoretical considerations. In presence of waves, the escaping droplets fly into the air but, being adhered to the crater, get stretched and broken into secondary droplets. For smaller angles, the droplets escape the crater and glide along the interface. The gliding droplet creates a chain of small craters in its wake. The rims between the craters may grow and get scattered into secondary droplets. Large liquid viscosity and small thickness of the liquid layer suppress the growth of the craters and secondary entrainment. Bubble entrapment during such impacts most likely occurs due to crater collapse with trapping air inside. However, such air pockets are not formed systematically in the present model. This discrepancy requires further investigation.

Physicochemical Quality of Oyster Mushroom for Functional Food

This article presents studies on the physicochemical quality of oyster mushrooms grown within a housing and controlled by the Internet of Things (IoT). The goals of this study were to assess (1) the impact of indoor air quality on the growth and quality of mushrooms and (2) the antioxidant content of oyster mushrooms. In this study, the air temperature and humidity of oyster mushroom house per unit time was recorded and controlled automatically by an IoT system. Additionally, their physicochemical and microbiological quality were evaluated using physico-analytical instruments, and the potency of their ergothioneine (EGT) content was investigated using the HPLC method. The temperature of the air inside was between 29 and 35 °C, and the relative humidity was between 60% and 90%. The average texture of mushroom is soft. The average length, width, and height of the fresh mushroom were 41.5 mm, 60.0 mm, and 29.5 mm, respectively. The microbiological test confirmed that there was no salmonella infection in the collected mushrooms. The button-stage mushrooms have less total fungus than the bloom-stage mushrooms. The extraction standard method employs an EGT content of 0.674 mg/g as determined by chromatography data analysis. The oyster mushrooms can be consumed as a healthy meal, and the study of EGT showed also very prospective as one of immunotherapeutic food. Keywords: Ergothioneine, Fibre-reinforced plastic house, Internet of think, Oyster mushrooms

Fully optic characterization of acoustic impedance implementable in conventional optical microscope

The intrinsic acoustic impedance (Z) changes with inflammation and canceration. This paper proposes an optically Z measurement method using a common optical microscope for simultaneous measurement of optical-acoustical observation. Photoacoustic (PA) waves were generated by the PA effect of the pulsed laser (a 527 nm nanosecond laser light) at the black ink and resin pasted area on the outside of the bottom of the petri dish (surface A). The generated PA waves propagated to the inner boundary of the petri dish and reflected, with a reflection coefficient of R. The reflected waves propagated to surface A and vibrated it. The surface vibration was measured with a self-built Sagnac interferometer using a contentious light laser and a 10x objective lens. Measurements were made air-filled and water-filled petri dishes. The observed times of echo signal corresponded to the sound speed of longitudinal and transverse propagation. The reflected wave amplitude of air was larger than in a water-filled petri dish. They related that R water and R air are 0.24 and 1.00, respectively. There corresponds to the Z ratio of the polystyrene petri dish and the water or air inside. Thus, this result showed that sample Z was measured optically.

Cfd Analysis in Coaxial Injector of a Cryogenic Rocket Engine And Evaluation of Atomisation Characteristics Using Simulant Fluids

A Study of atomisation and mixing of 2-phase propellants using simulant fluids injected from a coaxial injector of an operating cryogenic rocket engine is carried out and presented along with the CFD analysis of flow within it. The original injector jet (Jet 3) designed, modeled and analysed has swirl for LOX (water) alone with GH2 (air) having no swirl. Injector jet having inner casing and outer sleeve is modeled using I-DEAS software and analysed for inner core fluid domain (liquid) and annular fluid (air) domain. Results of flow analysis inside jet revealed asymmetric nature of air flow at exit due to the air fluid domain itself is not axisymmetry in the original jet. This non-axisymmetry of 2-phase fluids at the exit of injector jet will obviously affect the characteristics of atomisation and mixing of fluids. Data obtained from atomization experiments done on this jet using stimulant fluids (water in LOX side and air in GH2 side) such as particle distribution and Sauter Mean Diameter (SMD), fairly matches with the predictions made using CFX software and associated codes which enabled to evaluate the analysis software. Further, the air flow at exit has been made axisymmetric by modifying the air passage in the injector jet (Jet 3 Mod) and the effect of this modification on atomisation and mixing of 2-phase fluids is predicted using the CFX software. In combustion better efficiency with less instability is to be attained. For meeting both simultaneously articles size distribution after injection has to be neither very finer nor coarse. Comparison of predicted data on atomisation revealed that the modified Jet (Jet 3 Mod) is relatively better to give stable combustion with higher performance.

Analisa Pengelolaan Lingkungan Gedung X Terhadap Kualitas Udara dan Air

Air quality and air are very important for human health and comfort. Good quality air can ensure enough oxygen for the human body, while good quality water can meet the water needs of the human body and other needs. However, the quality of air and water in some places can be disrupted by various factors, such as air and water pollution, and poor environmental management. Therefore, it is important to conduct research on air and water quality to determine their level of cleanliness and take the necessary action to maintain or improve it. This research aims to analyze the air and water quality in Building X, as well as the factors that affect it, so that it can provide useful information for maintaining good air and water quality. The research method used is a document study that begins with conducting a critical review of the evaluation matrix for environmental management efforts in the Environmental Impact Assessment Document of Building X in Sleman District. The results of the study show that the environmental management of buildings affects the air and water quality inside. Good management can ensure the quality of air and water that is healthy and comfortable for building occupants, and help reduce negative impacts on the environment

Assessing pupils’ understanding about greenhouse effect in context of problem-based approach in environmental education: A case study from Greece

The greenhouse effect is a process that regulates the temperature of the planet. Students have misunderstandings about the greenhouse effect. The misunderstandings about the greenhouse effect may result from the direct analogy of a greenhouse as a means to maintain the heat by preventing convection and trapping warm air inside. The main research question has to do with the extent that pupils understand the greenhouse effect as an environmental problem. The sample consisted of 18 pupils of a 4th grade Primary school classroom forming case study research. The analysis of answers was mainly based on qualitative grounds, by examining the way pupils express their opinions or beliefs about this specific environmental topic. Students’ answers present that they understand enough the greenhouse effect both as a natural process and as environmental problem. They seem to present a lower understanding about its causes, but a mediocre understanding about consequences and interesting suggestions about how to solve it. As far as the use of accurate or scientific words is concerned, the statements seem to be on a low level. In conclusion, it can be supported that problem-based teaching intervention can contribute to pupils’ understanding about environmental problems such as the greenhouse effect.

Genesis of "negative pressure" during hanging drop; the answer is positive pressure.

A drop of saline placed within the hub of an epidural needle is sucked in when the needle is advanced and penetrates through a polyurethane foam cube. This phenomenon might be explained by the release of compressed air inside of the needle into the air. The positive pressure inside of the needle may be generated by advancing of the needle. To prove this hypothesis, the pressure inside of the needle was measured during needle advancement, and it increased gradually and then dropped to zero suddenly when the needle fully penetrated the polyurethane foam block. We can speculate that the same phenomenon occurs during hanging-drop method of epidural anesthesia, and this may occur regardless of whether epidural subatmospheric pressure exists or not.

Numerical analysis of effects of fins and conductive walls on heat transfer in side heated cavities — Onset of three-dimensional phenomena in natural convection

In the present study, we analyse individual and combined effects of conductive horizontal walls and conductive fins on the natural convection of air in side heated cavities (SHC). The flow and heat transfer are studied for Rayleigh numbers in the range of 104−109: Direct Numerical Simulation (DNS) is conducted for the lower and Large Eddy Simulation (LES) for the higher Rayleigh numbers (>108). Thermally conductive walls destabilize the flow yielding an earlier transition to turbulence and expedite the decay in boundary layer thickness with increase in Rayleigh number. The preheating/precooling along the conductive walls reduces the actual heat transfer at the vertical walls. Above the fin, instabilities are only marginally enhanced for adiabatic horizontal walls, whereas for conductive horizontal walls, plumes erupt from the fin. This localized Rayleigh-Bénard-like effect triggers 3D instabilities in the entire flow field and yields a steeper slope in Nusselt-Rayleigh diagram. The presence of a fin increases the integral heat transfer by 18% for adiabatic and 21% for conductive horizontal walls. We show that 2D and 3D simulations are similar for the smooth cases (i.e., without fin), but differ by 4% and 13% for the adiabatic and conductive fin cases respectively. The local heat transfer characteristics even deviates up to 50%, therefore a 2D simplification should be avoided.

Incidental paratracheal air cyst in papillary thyroid cancer patient: a case report

Paratracheal air cyst (PTAC) is a collection of air in the right posterior side of the trachea with an uncertain etiology. We report a papillary thyroid cancer patient with a PTAC that was removed during thyroid cancer surgery. A 68-year-old woman was diagnosed with right papillary thyroid cancer with suspicion of central lymph node metastasis. She had a history of hypertension and a rear-end collision car accident 20 years prior. On computed tomography, an ovoid cyst was incidentally found in the paratracheal region at the thoracic inlet level. Emphysematous lung with an obstructive lung defect was noted without any symptoms. Bilateral total thyroidectomy with ipsilateral central compartment neck dissection was indicated for the patient. During surgery, removal of the cyst was inevitable for complete central neck dissection. Histopathologic analysis revealed an etiology of tracheal mucus sprouting through weak trachea points. No postoperative complications occurred. The patient continued on levothyroxine medication without further radioactive iodine therapy. After 6 months, follow-up ultrasound showed no evidence of recurrence. We hypothesized that obstructive lung disease with impaired lung function or trauma history might have contributed to the development of PTAC. Future studies are needed to determine if PTACs have any association with obstructive lung disease or trauma.

Effect of submarine microclimate on respiratory physiology of submariners: An observational study

Introduction: A few personnel feel more tired staying and working inside submarine, as compared to ashore/outdoor spaces, or even onboard afloat platforms (ships). The microclimate onboard underwater platforms play a vital role in determining the respiratory physiology parameters of personnel onboard. There exists a felt need for deeper evidence in this regard. Aims and Objectives: This study is an effort to analyze if there exists any relationship between concentrations of respiratory gases (such as oxygen and carbon dioxide) and other parameters of submarine microclimate, on the respiratory physiology parameters (such as respiratory rate [RR] and SpO2) of personnel onboard underwater platforms. The difference in concentrations of oxygen and carbon dioxide in exhaled air of personnel both inside and outside submarine was also studied. Any difference between smokers and nonsmokers regarding this parameter was also evaluated. Materials and Methods: The study was carried out on thirty healthy volunteers posted onboard a submarine. Concentrations of oxygen and carbon dioxide in the atmosphere, as also the exhaled air, were measured using a digital gas analyzer. Humidity, temperature, and oxygen saturation were measured using digital meters. The values both inside and outside were recorded and compared. Results: There was a statistically significant difference in the temperature, humidity, and level of CO2 inside and outside the submarine. There was no statistically significant difference in level of oxygen in atmosphere, oxygen and carbon dioxide in exhaled air, RR, and SPO2 level inside and outside the submarine. Conclusion: The corrected effective temperature inside a submarine is to be measured periodically and maintained in the comfort zone. The level of CO2 should be maintained close to environmental levels.

Pleasure and Purpose in Gail Scott's Heroine

Pleasure and Purpose in Gail Scott's Heroine Camille Roy (bio) Why doesn't pleasure matter more? This question came to mind as I slowly read (the better to savor) Gail Scott's re-issued novel Heroine (2019). Set in the late 1970s but read in 2021, in a time of pandemic and lockdown, the social and erotic life of this brilliant feminist novel was almost deliriously engrossing: "The air smells of people, her perfume and the earth swelling due to irrigation from spring runoff. I feel euphoric. My nose moves closer to her wall of silk" (Scott 69). Pleasure is often contextualized with theory in order to be something other than dumb; bodily sensation undermines intellectual credibility. How wrong this is. It also forestalls attention to questions of interest related to narrative and narrative structure. For example, how does one construct a sentence (which has political aims) with pleasure as one of its rationales? What is the argument, implicit or otherwise, of a book which proceeds through time via pleasure? Doing and undoing are different projects. If pleasure can be an organizing force in life, what occurs as a result? Let's begin with the pleasure of foraging through the world, with curiosity, seeking delight. Begin with Montreal itself. The city is capacious and present throughout Heroine, in every physical and social sense. Sex workers, lesbians, communists, cafés, political meetings, actions, and their arguments all have their fire. The present time of the text has a particular gleam: Walking to the bank she notices the sky has a flat and shiny quality, like a knife-blade. Opening the bank door, she [End Page 393] senses the air inside is thin as cellophane. The woman next in line, with aquiline nose, curly hair, and coat open over enormous breasts, immediately starts talking. Complaining about how the bank is exploiting ordinary people with its long lines. Eventually she discloses her father was a socialist journalist in Vienna. The heroine nods sympathetically. (169) By degrees it becomes clear that the whole book is narrated by a woman in a bathtub. Her ruminations shift back and forth in time like a bead on a wire. Periodically she pauses to pleasure herself: "Please, froth, fall gently now on my small point. Sometimes after a while it gets so sore I call it my dolorous reptile" (66). The arc of knowing begins with desire. From this small point her consciousness roams across the city. Heroine handles the ungraspable complexity of a city by spilling out into ancillary characters, narratives, and refrains. This seems to also reflect the impish quality of a narrative organized around pleasure—there is always another provocative and tasty distraction. The threads do not need to intersect. A little girl in a yellow raincoat is fleeing a sandwich man. Her narrative of chase, hiding, escape recurs across the book. Prostitutes stream across the pages, stamping in the cold, warming up in the cafes: "Some hookers were standing round drinking hot chocolate. One was so wired up she kept doing a high step still holding her cup. Right leg over left leg. Twice. Left leg over right" (15). Such episodes create a rhythmic stride across the text. The subject to which she always returns is romantic obsession: "In the ecstasy of hayflowers my singing body couldn't get enough. As if it were being penetrated by a butterfly" (53). Her male lover is one of the leaders in a radical left group. Politics is both his epic romance and a domineering logic. He tells her, "The human race has but two choices, barbarism or Marxist revolution" (46). Revolutionary ardor is his justification for elusiveness and infidelity. She is caught in a deeply desired but utterly unsatisfying relationship. Lust, disappointment, ravenous need, and insecurity all oscillate; through frustration the novel accumulates a kind of density. This portrait of relationships on the left at that time reminded me of my old friend L. She was a member of the Detroit Chapter of the Weather Underground [End Page 394] in the 1970s. She once told me (with the satisfaction of a comeuppance) that what destroyed the organization was not the FBI or the police but...

Key problems in early wine-spirit thermometers and the “true Réaumur” thermometer

The main problems of early wine-spirit thermometers, with special reference to the eighteenth century, are considered with a holistic approach based on historical sources, physical mechanisms, and mathematical relationships. Thermometers were hardly comparable and were vulnerable at extreme temperatures, including calibration. Wine-spirit and the vapor pressure exerted at different temperatures, especially in proximity of the boiling points of spirit and water, are analyzed, because they caused the failure of glass tubes. The method suggested by Reaumur of completely removing air from the tube when it was sealed and the opposite one by Micheli du Crest of leaving some air inside are discussed, as well as advantages and disadvantages of using wine-spirit at different mole fractions of ethyl alcohol and water. The original, so-called “true Reaumur” thermometer, its calibration, scale, and response are investigated. The equations that evaluate the deviation from linearity for various factors are derived. Equations are given to convert readings taken with the “true Reaumur” and other early thermometers to Celsius, and at the same time correcting them from the departures due to wine-spirit and the particular calibration. Finally, the direct Celsius scale has been found to be known earlier than believed, in 1740.

Thermal performance enhancement studies on a circular finned coil-in-shell heat exchanger using graphene oxide nanofluid

The objective of this study is to investigate the effect on heat transfer augmentation by the combined effect of circular fins directly attached to the helical surface of the coil in two different orientations (45° and 90°) and Graphene Oxide nanofluid as a heat transport agent, in a coil-in-shell heat exchanger. The attached circular fins not only act as turbulators on the shell side but could also add to heat transfer from the hot side to the cold side, by a combined mechanism of conduction and convection. The experiment is conducted at constant heat flux, with the cold nanofluid in the coil side and hot air in the shell side. Test runs are taken by varying hot air velocities from 1 m/s to 5 m/s, keeping fixed volume concentration of nanofluid (0.05–0.15%) and flow rate (500 ≤ Re ≤ 5500) one at a time. Experimental results indicated significant enhancement in heat transfer performance for the finned configuration. For 90º and 45º fin orientation—0.15% volume concentration of nanofluid, the maximum heat transfer increase is by 78.46%, and 82.22%, Nusselt number increase is by 32.57%, 60.79% respectively, at a hot air velocity of 3 m/s. The coil side pressure drop and friction factor increased to 32.72% and 24.64% for 0.15% GO nanofluid when compared to pure water at the maximum flow rate. The thermal–hydraulic performance improvement is nearly two-fold with 45º fin orientation-GO nanofluid combination.

Mürdümük (Lathyrus sativus L.) ve Tritikale (xTriticosecale Wittmack) Karışımlarının Silaj Kalitesinin Belirlenmesi

Bu çalışmada, Mardin ili Kızıltepe ilçesi ekolojik koşullarında, sulu şartlarda yetiştirilen Mürdümük (Lathyrus sativus L.) ile Tritikale (xTriticosecale Wittmack) hasıllarının farklı oranlarda karıştırılması ile elde edilen silajların kalite özelliklerinin araştırılması amaçlanmıştır. Kızıltepe ilçesi Köprübaşı Mahallesi çiftçi arazisinde 2016-2017 ve 2017-2018 yetiştirme sezonun yürütülen bu çalışmada bitki materyali olarak GAP Mavisi mürdümük çeşidi ile Tatlıcak-97 tritikale çeşidi kullanılmıştır. Çalışmada %100 mürdümük, %100 tritikale, %80 mürdümük + %20 tritikale, %60 mürdümük + %40 tritikale, %40 mürdümük + %60 tritikale, %20 mürdümük + %80 tritikale karışım oranları kullanılmıştır. Silajlanacak materyal, gofrajlı vakum poşetlerine 1 kg’lık karışımlar halinde konularak lavion marka vakum makinesi ile içinde hava kalmayacak şekilde 3 tekerrür olarak hazırlanıp vakumlanmıştır. Vakumlanmış poşetler 45 gün sonra açılarak fiziksel (renk, koku ve strüktür) ve kimyasal (silaj pH değeri, ADF, NDF, ham protein, ham kül, kuru madde ve laktik asit oranları) özellikleri incelenmiştir. Fiziksel özellikler bakımından nitelik sınıfı en yüksek %100 tritikale silajından elde edilmiştir. Kimyasal özellikler açısından bakıldığında; pH değeri için %100 tritikale silajı, kuru madde oranı %100 tritikale silajı, ADF oranı %100 mürdümük silajı, NDF oranı %100 mürdümük silajı, ham protein %100 mürdümük silajı, ham kül %100 tritikale silajı, fleig puanı ise %100 tritikale silajından elde edilmiştir. Tüm analiz sonuçları incelendiğinde farklı oranlarda karıştırılan Mürdümük+Tritikale silajı için %80 mürdümük + %20 tritikale silaj karışımı uygun bulunmuştur.

Bubbles Moving in Blood Flow in a Microchannel Network: The Effect on the Local Hematocrit.

Air inside of blood vessels is a phenomenon known as gas embolism. During the past years, studies have been performed to assess the influence of air bubbles in microcirculation. In this study, we investigated the flow of bubbles in a microchannel network with several bifurcations, mimicking part of a capillary system. Thus, two working fluids were used, composed by sheep red blood cells (RBCs) suspended in a Dextran 40 solution with different hematocrits (5% and 10%). The experiments were carried out in a polydimethylsiloxane (PDMS) microchannel network fabricated by a soft lithography. A high-speed video microscopy system was used to obtain the results for a blood flow rate of 10 µL/min. This system enables the visualization of bubble formation and flow along the network. The results showed that the passage of air bubbles strongly influences the cell’s local concentration, since a higher concentration of cells was observed upstream of the bubble, whereas a lower local hematocrit was visualized at the region downstream of the bubble. In bifurcations, bubbles may split asymmetrically, leading to an uneven distribution of RBCs between the outflow branches.

SARS-Cov-2 Delayed Tokyo 2020 Olympics: Very Recent Advances in COVID-19 Detection, Treatment, and Vaccine Development Useful Conducting the Games in 2021

The novel coronavirus (SARS-Cov-2) delayed the Tokyo 2020 Games. The traveling by air, rail, road, and sea inside and outside the countries has stopped to contain the virus. The amount of money lost and assistance needed to reschedule and conduct the Games in 2021 have been estimated. With more than one billion population is under the semi-locked down and movement of people is restricted, athletes cannot prepare at home and participate in the Games. The COVID-19 outbreak has spread around the world; it has already infected 5.7 million people and caused 355,000 deaths reported on May 28, 2020 and the figures increasing every day. The publication of this article is important as the postponement of the Olympics has costed Japan $6 billion and the organizers have worked very hard for seven years. If the Games are conducted in 2021, it will be the—beginning of the world recovery—from big COVID-19 pandemic. In this communication, the development in testing, treatment, and vaccine preparation for SARS-Cov-2 have occurred so far in different countries and companies have been discussed to know the possibilities if the pandemic can be overcome and the Games can be conducted in 2021.

Study on the temperature dependence of gas permeation and adsorption behavior of the vacuum insulation panel with getter materials

Vacuum insulation panel (VIP) is a high-performance heat insulation material that has contributed to the energy efficiency of refrigerators, vending machines, and cooler boxes. Glass wool or fumed silica covered by a laminated film are the core materials of VIP; by evacuating air inside, it is possible to reduce the gas thermal conductivity to be close to 0 and exhibit high thermal performance. In recent years, the research on long-term performance prediction has been conducted for use in building insulation. Specifically, various getter materials have been developed to improve the long-term performance of glass wool VIP. However, there are no studies that clearly show the adsorption behavior or temperature dependence inside VIP with getter materials. We measured the adsorption temperature dependence of two types of getters using the constant volume method and then observed the adsorption behavior inside VIP using VIP equipped with a micro pressure sensor. Regarding the internal pressure of VIPs equipped with the micro pressure sensor, the pressure fluctuation derived from the adsorbent was confirmed by the temperature change, and it was confirmed that the thermal conductivity changed accordingly. If the internal temperature of VIP increases, gases may be released from the getter. Therefore, in the building environment, it is necessary to select a getter that is suitable for the usage environment and to use an appropriate amount of getter.

Thermal Design of a Shell and Tube Heat Exchanger with Internal Fins

To alleviate the severe challenge of energy depletion, it’s extremely urgent to improve the available heat recovery technology. Heat exchangers play a key role in waste heat recovery and have attracted much attention. To recover waste heat, a shell and tube heat exchanger with sinusoidal wavy fins and blocked-core tube inside the tube, and with bare surfaces outside was designed by segmented log-mean temperature difference (LMTD) method. In the shell and tube heat exchanger, liquid water outside the tube was heated by compressed air inside. The effect of air-side inlet pressure on the geometry of heat exchanger was investigated under identical temperature conditions (Ta,i, Ta,o, Tw,i, Tw,o) and water-side inlet pressure. The results show that air-side inlet pressure has little effect on the structure parameters of heat exchanger, but greatly affect the pressure drop of air side.