Numerical Analysis of Smoke Behavior and Detection of Solid Combustible Fire Developed in Manned Exploration Module Based on Exploration Gravity

A fire during manned space exploration can cause serious casualties and disrupt the mission if the initial response is delayed. Therefore, measurement technology that can detect fire in the early stage of ignition is important. There have been a number of works that investigate the smoke behaviors in microgravity as the foundation for a reliable method for sensing a fire during spaceflight. For space missions to the outer planets, however, a strategy of detecting smoke as an indicator of fire should be adjusted to cover the fire scenario that can be greatly affected by changes in gravity (microgravity, lunar, Mars, and Earth gravity). Therefore, as a preliminary study on fire detectors of the manned pressurized module, the present study examined the smoke particle behavior and detection characteristics with respect to changes in gravity using numerical analysis. In particular, the effects of the combination of buoyancy and ventilation flow on the smoke particle movement pattern was investigated to further improve the understanding of the fire detection characteristics of the smoke detector, assuming that a fire occurred in different gravity environments inside the pressurized module. To this end, we modeled the internal shape of Destiny and performed a series of numerical analysis using the Fire Dynamics Simulator (FDS). The findings of this study can provide basic data for the design of a fire detection system for manned space exploration modules.

Parametric Investigation of Photochemical Machining of SS- 430 for Manufacturing of Micromesh

Photochemical machining (PCM) is an emerging method for machining of very thin and difficult-to-cut material with complex geometrical profile. PCM is one of recommended method for machining of aerospace components, biomedical appliances, electronics part and decorative items. High corrosion resistance, better life, good appearance and strength recommend SS-430 as suitable material for various applications. In the current investigation, the parametric investigations of process parameters in photochemical machining for concentration and temperature of etchant, time of etching is done through ANOVA analysis. Grey Relational Analysis is performed to estimate the optimum machining parameters during PCM of SS-430. Formulation of mathematical model is done for prediction of results. Taguchi (L27) experimental array is used for Design of Experiments (DoE). The significance process parameters are estimated to govern the process with F-Values. Confirmatory test is conducted to observe the improvement in the responses. ANN predictive model is built up for investigation of error between predictive and experimental values. The obtained optimum set is used for manufacturing of micromesh typically used in smoke detector to safeguard human life.

CFD analysis on the effect of temperature on gas distribution in indoor environment

There are times when people are required to spend time indoors, especially due to unhealthy outdoor air quality as well during a pandemic when lockdowns are imposed. However, spending time indoors can also at times be dangerous due to the release of harmful gasses if left unchecked. This has very much to do with many parameters, among which is the indoor environment and its ventilation. The latter is affected by the way gases distribute inside the building. It is influenced by many factors such as temperature, wind, air circulation, and also ventilation system itself. The knowledge on how the gases spread in different conditions within the indoor environment can be utilized in many applications such as improving the smoke detector safety system and identifying as well as predicting the potential risks. This paper presents the investigation of the effect of different temperatures on gas distribution in an indoor environment. A three-dimensional simulation was performed of different temperature gas released in a closed room that has different ambient temperatures. The effect of temperature on the gas dispersion was observed. The results revealed that there is a significant effect of temperature on the way gas spread in the indoor environment support by the theoretical knowledge on the relationship between temperature and gas in the gas law.

Design of Smoke Detector for Smart Room Based on Arduino Uno

Smoke is one of the air pollutions that is very detrimental to the health of both the smoker himself and others around him. Inhaling other people's smoke is even more dangerous than inhaling your own smoke. Even the dangers that must be borne by passive smokers are three times greater than the dangers of active smokers. Smoke is also very detrimental to the health of patients in hospitals, especially patients who suffer from asthma. For people with asthma who have problems in the respiratory tract, asthma can recur at any time due to inhaling smoke. This research will develop a smart room that can detect smoke to maintain and protect the room from smoke that interferes with health. The tool to be developed uses an MQ2 sensor, LCD, exhaust fan, buzzer, and Arduino Uno microcontroller. Where an MQ2 sensor is needed to detect smoke around it, an LCD is needed to display the percentage of smoke, a microcontroller as a controller for all components, a buzzer is used as an alarm when the smoke level in the room is unhealthy, and the exhaust fan functions as a sucker for dirty air so that the smoke level in the room can be reduced.

Study on Smoke Detector Characteristics Using Fire Simulations

To reduce the damage caused by fire detector malfunctions, we investigated the standards and literature pertaining to fire detectors in Korea. The domestic standards cite UL's technical specifications, which provide only the standards and types of combustible materials; however, additional research is needed because no facilities related to the experiments are investigated and no fire experiments have actually been conducted. In this study, we refer to UL 268, which is similar to the domestic standards, as well as detailed experimental conditions and methods to improve smoke detector performances; we also use wood as the combustion material from among the fire sources specified in UL 268. Experiments were conducted to measure the sensitization rates using an optical density meter and repeated to match the wood smoke profile standard provided in UL 268. Furthermore, we compared the smoke concentrations detected by the smoke detectors in the fire experiments with those from fire simulations using FDS software to confirm the detector characteristics. Through these comparisons, we show that this research could be used as preliminary data for performance testing of detectors using UL 268.

Analysis of Supervised Machine Learning Techniques for Diagnosis of Disease of Infant Baby

A system for monitoring an infant's health is developed and described in this paper. In this system, smoke detector, sound sensor, temperature and humidity sensor, are interfaced with the controller Node MCU-ESP8266. In the system, ThingSpeak Cloud is used for the data processing. ThingSpeak Cloud is connected to the Wi-Fi based microcontroller. The behavior and the problems that are being detected can be easily notified to the parents apart from the doctors and nurses, So, that even the nurses or the doctors misses out by chance, the parents can handle the scenario. The collected data can be taken out as in the form of the csv format. This data can be easily put into the Machine Learning Model in order to predict the various problems that a baby might be suffering from. These predictions have been done solely upon the data collected from the individual baby. Furthermore, separate system-based report would be facilitated by the model itself

Estimation of Magnitude and Heat Release Rate of Fires Occurring in Historic Buildings-Taking Churches as an Example

Historical buildings often fail to meet today’s building and fire protection regulations due to their structure and space restrictions. For this reason, if such buildings encounter fire, serious damage will be resulted. The fire of the Notre-Dame Cathedral in Paris (Notre-Dame de Paris) in April 2019 highlights the seriousness of this problem. In this study, the historical building of “Tamsui Church” was selected as an example. The Fire Dynamics Simulator (FDS) was adopted to analyze the scale of damage and possible hazards when the wooden seats in the church are on fire, and improvement measures were proposed to ensure that such buildings can be used under safer conditions. It was found that the existing seat arrangement will cause the spreading of fire, and the maximum heat release rate is 2609.88 kW. The wooden roof frame above the fire source will also start to burn at 402.88 s (6.6 min) after the fire, which will lead to a full-scale fire. To maintain the safety of the historical building, it is necessary to add active firefighting equipment (smoke detector and water mist system).

Sistem Pemantauan dan Pendeteksi Kebakaran berbasis Logika Fuzzy dan Real-time Database

ABSTRAKKebakaran rumah seringkali disebabkan oleh kelalaian manusia. Oleh karena itu diperlukan sebuah sistem yang dapat mendeteksi kebakaran secara online realtime. Pada studi ini, dirancang dan diimplementasikan sebuah sistem pendeteksi kebakaran dengan sejumlah sensor untuk mengukur beberapa parameter lingkungan. Sistem ini dilengkapi dengan pengambil keputusan menggunakan metode fuzzy logic. Parameter lingkungan yang diukur mencakup suhu ruangan, asap dan api yang kemudian dapat dimonitor secara real-time melalui web interface menggunakan Internet of Things platform. Pengujian menunjukkan bahwa detektor dapat mendeteksi api dengan jarak hingga 100 cm dengan akurasi mencapai 100%. Pengujian sensor suhu menunjukkan akurasi 98.79%, sementara itu detektor asap memperoleh akurasi 77.81%. Sistem ini mampu mengirimkan data dengan rata-rata delay transmisi 0.62 detik. Sistem usulan ini diharapkan dapat menyediakan pemantauan kondisi suatu ruangan secara real-time.Kata kunci: Kebakaran, Real-Time, Deteksi, Fuzzy, Internet Of Things ABSTRACTHouse fires are often caused by human error. Therefore, we need a system that can detect fires online real-time. In this study, a fire detection system with a number of sensors is designed and implemented to measure several environmental parameters. This system is equipped with a decision maker using the fuzzy logic method. The environmental parameters measured include room temperature, smoke and fire which can then be monitored in real time via a web interface using the Internet of Things platform. Tests show that the detector can detect fires with a distance of up to 100 cm with an accuracy of up to 100%. The temperature sensor test shows an accuracy of 98.79%, while the smoke detector generates an accuracy of 77.81%. This system is capable of sending data with an average transmission delay of 0.62 seconds. This proposed system is expected to provide realtime monitoring of the condition of a room.Keywords: Fire, Real-time, detection, Fuzzy, internet of things