scholarly journals Analysis of the Risk of Heat Generation due to Bolt Loosening in Terminal Block Connector Parts

2020 ◽  
Vol 34 (3) ◽  
pp. 67-75 ◽  
Author(s):  
Yeong-Mo Yeon ◽  
Seung-Hee Kim
Keyword(s):  
Real Time ◽  
Heat Generation ◽  
Heating Temperature ◽  
Electrical Contact ◽  
Thermal Characteristics ◽  
Risk Level ◽  
Industrial Sites ◽  
Temperature Detector ◽  
Measurement And Analysis ◽  
Terminal Block

In this study, the risk of heat generation due to normal and overload currents that vary with the abnormal loosening angle of wire-connecting bolts were identified. The risks were analyzed based on the thermal characteristics to minimize the carbonization accidents of terminal blocks inside distribution panels typically used in industrial sites. We applied a method for measuring the heating temperature and temperature variations in the terminal blocks in real-time by installing a resistance temperature detector sensor board in the terminal block. The experimental results showed that the terminal block model with a low-rated current exhibited a higher heating temperature, thus, confirming the need to select the terminal block capacity based on load currents. Additionally, the higher the rated current of the terminal block with a high-rated current and the higher the degree of loosening, the faster the carbonization point. Such heating temperature monitoring enabled real-time thermal temperature measurement and a step-by-step risk level setting through thermal analysis. The results of the measurement and analysis of carbonization risks can provide a theoretical basis for further research regarding the risk of fire due to carbonization. Furthermore, the deterioration measurement method using the temperature sensor board developed in this study is widely applicable to prevent fires caused by poor electrical contact as well as risk-level management.

scholarly journals Diagnosis of Abnormal Heat Generation in the Connection Part in Low Voltage MCCBs for Fire Risk Prediction

2020 ◽  
Vol 34 (5) ◽  
pp. 42-49
Author(s):  
Yeong-Mo Yeon ◽  
Seung-Hee Kim
Keyword(s):  
Heat Generation ◽  
Low Voltage ◽  
Circuit Breaker ◽  
Thermal Characteristics ◽  
Saturation Temperature ◽  
Fire Risk ◽  
Industrial Sites ◽  
Phase Temperature ◽  
Normal Current ◽  
Temperature Test

This study is conducted to determine the critical temperature under normal current flow by estimating normal heat generation; the saturation temperature of the connecting part of a circuit breaker is simultaneously measured by sub-dividing the rated current of molded case circuit breaker (MCCB) into 10 steps. Further, a risk analysis was conducted via an investigation of thermal characteristics. To this end, five types of MCCBs were selected while building a temperature test box; further, the heat generation temperature of the three phases on the line and load sides was measured using the sub-divided load current to represent the electrical heat variation and a high-current-generating tester real-time. The results the test, demonstrate that the temperature of the connecting part of the MCCB stably increased; in addition, the standard of the heat generation could be established and the load amount could be predicted by measuring the temperature variation. Meanwhile, the heat generation temperature was different for different types of wirings such as power lines and Busbar. Further among the R, S, and T phases of the MCCB, S phase temperature was slightly higher than those of the others. This study can serve as a theoretical reference for future applied research on the dangers of fire due to the heat generation of the connecting part of the MCCB, wherein the risks of abnormal heat generation need to be analyzed. The results obtained can be applied not only to prevent the carbonization accidents of MCCBs installed inside distribution panels being used at industrial sites, but also to manage the risks of the distribution circuit breaker and prevent the electrical fire.

An expert system for real-time well field management

2012 ◽  
Vol 12 (5) ◽  
pp. 699-706 ◽  
Author(s):  
B. S. Marti ◽  
G. Bauser ◽  
F. Stauffer ◽  
U. Kuhlmann ◽  
H.-P. Kaiser ◽  
...  
Keyword(s):  
Drinking Water ◽  
Expert System ◽  
Knowledge Base ◽  
Real Time ◽  
Urban Areas ◽  
Industrial Sites ◽  
Water Wells ◽  
Well Field ◽  
Field Management ◽  
Historical Management

Well field management in urban areas faces challenges such as pollution from old waste deposits and former industrial sites, pollution from chemical accidents along transport lines or in industry, or diffuse pollution from leaking sewers. One possibility to protect the drinking water of a well field is the maintenance of a hydraulic barrier between the potentially polluted and the clean water. An example is the Hardhof well field in Zurich, Switzerland. This paper presents the methodology for a simple and fast expert system (ES), applies it to the Hardhof well field, and compares its performance to the historical management method of the Hardhof well field. Although the ES is quite simplistic it considerably improves the water quality in the drinking water wells. The ES knowledge base is crucial for successful management application. Therefore, a periodic update of the knowledge base is suggested for the real-time application of the ES.

Measurement and Analysis on Transient Thermal Characteristics of High Speed Motorized Spindle

2011 ◽  
Vol 52-54 ◽  
pp. 2021-2026
Author(s):  
Gui Ling Deng ◽  
Can Zhou
Keyword(s):  
High Speed ◽  
Thermal Deformation ◽  
Thermal Characteristics ◽  
Measuring System ◽  
Test Results ◽  
Motorized Spindle ◽  
Measurement And Analysis ◽  
Turning Center ◽  
Transient Thermal ◽  
Deformation Compensation

Thermal deformation is an important factor to affect the accuracy of the motorized spindle, the core component of high-speed machine tool. To understand the spindle system transient thermal characteristics of the high-speed turning center CH7516GS, some high-precision sensors and high-frequency data acquisition system is used to establish the temperature and displacement measuring system. The thermal deformation compensation model is established on the basis of the experimental test results.

Dynamic Temperature Testing and Modeling for an Automatic Transmission Clutch

2001 ◽  
Author(s):  
Thomas DeMurry ◽  
Yanying Wang
Keyword(s):  
Experimental Data ◽  
Real Time ◽  
Automatic Transmission ◽  
Thermal Characteristics ◽  
Torque Converter ◽  
Telemetry System ◽  
Temperature Model ◽  
And Control ◽  
Good Agreement ◽  
Dynamometer Test

Abstract The primary objectives of this study are (1) to validate the hardware design and control methodologies for preserving the thermo-mechanical integrity of a launch clutch emulating a torque converter and (2) to develop a simple, control oriented clutch-temperature model that may act as a virtual thermocouple in the processor of an automobile for real-time clutch-temperature predictions. In a dynamometer test cell, a Ford CD4E transaxle is instrumented with a thermocouple-based telemetry system to investigate clutch thermal characteristics during engagements, neutral idle, single and repeated launching, torsional isolation, and hill holding. A nonlinear, SIMULINK™-based model for estimating temperature is developed. The results from the simulations are in good agreement with the experimental data.

scholarly journals Compact USB measurement and analysis system for real-time fluctuation enhanced sensing

2011 ◽  
Author(s):  
Robert Mingesz ◽  
Zoltan Gingl ◽  
Akos Kukovecz ◽  
Zoltan Konya ◽  
Krisztian Kordas ◽  
...  
Keyword(s):  
Real Time ◽  
Measurement And Analysis ◽  
Time Fluctuation ◽  
Analysis System

Thermal Modeling and Experimental Investigation for Laser Assisted Milling of Silicon Nitride Ceramics

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
Xinwei Shen ◽  
Shuting Lei
Keyword(s):  
Silicon Nitride ◽  
Heat Generation ◽  
Feed Rate ◽  
Laser Power ◽  
Cutting Speed ◽  
Thermal Characteristics ◽  
Successful Operation ◽  
Element Analysis ◽  
Nitride Ceramics ◽  
Operating Temperatures

This study is motivated by the fact that temperature control is very important for the success of laser assisted milling. A transient three-dimensional thermal model is developed using finite element analysis for laser assisted milling (LAMill) of silicon nitride ceramics, and then validated through a series of experiments of laser assisted face milling. This study aims to explore the thermal characteristics in LAMill of silicon nitride ceramics and thus provide guidelines on parameter selection for future operations. In addition, heat generation associated with machining is considered, and the effects of laser power, feed, and cutting speed on temperature are investigated. Simulation results show that heat generation associated with machining can be neglected. Laser power is one critical parameter for successful operation of LAMill. Moreover, both feed and cutting speed can affect the operating temperatures by varying feed rate; however, once feed rate is fixed, they have a little impact on the operating temperatures.

scholarly journals Is it reasonable for the same city to advocate a policy of reducing heating temperature by the same amount?

2021 ◽  
Vol 233 ◽  
pp. 01143
Author(s):  
Shiqian Wang ◽  
Enshen Long ◽  
Ning Mao
Keyword(s):  
Energy Saving ◽  
Heating Temperature ◽  
Thermal Characteristics ◽  
Relative Energy ◽  
Office Building ◽  
Saving Ratio ◽  
The Government ◽  
Saving Effect ◽  
Saving Measure ◽  
New Buildings

Reducing heating temperature is a universally recognized energy saving measure. However, the same city has buildings completed in different years and with different functional USES at the same time. It is an important issue worth discussing whether it is reasonable for the government to advocate reducing heating temperature by the same range. Based on DOE medium-sized office building as the object, using the Beijing meteorological database system, the thermal characteristics of four envelopment structures representing different completion years, the annual heating energy saving and relative energy saving ratio when the set indoor heating temperature is reduced by the same range are studied. The results show that the worse the thermal performance of the envelope is, the greater the annual heating energy is when the heating setting temperature drops by the same extent. It indicates that the older the building is, the better heating energy saving effect and more heating cost can be achieved by advocating lowering the heating setting temperature of the same range. For the annual relative energy saving ratio, the older buildings with worse envelope structure are slightly higher, while the new buildings with better envelope structure are slightly lower, but they are similar on the whole. It is proved that the policy of reducing heating temperature by the same range in the same city is reasonable for achieving similar energy saving ratio.

MARINE-EO project: Monitoring and forecast of eutrophication around fish farms, a Maliakos Gulf case (Eastern Mediterranean).

2021 ◽  
Author(s):  
Amandine Declerck ◽  
Matthias Delpey ◽  
Thibaut Voirand ◽  
Ioanna Varkitzi
Keyword(s):  
Water Quality ◽  
High Resolution ◽  
Real Time ◽  
Chlorophyll A ◽  
Satellite Observation ◽  
Risk Level ◽  
Fish Farms ◽  
Ocean Modelling ◽  
Monitoring And Forecasting

<p>Keywords: eutrophication; high resolution ocean modeling ; Chla satellite data ; biogeochemistry</p><p>Maliakos Gulf corresponds to mesotrophic waters that can reach eutrophic conditions and are occasionally subject to Harmful Algal Blooms (HAB) (Varkitzi et al. 2018). At the same time, it is an important fish farming and aquaculture production area. A large issue is thus related to the monitoring and forecasting of the risk of occurrence of algae blooms in the Gulf. For this purpose, the present study couples predictions from a high-resolution numerical ocean model with satellite observation to improve the monitoring and anticipation of threats for the local fish farms induced by occasional eutrophication.</p><p>This solution is developed in the frame of the MARINE-EO project (https://marine-eo.eu/). It combines satellite observation with high-resolution ocean modelling to provide detailed information as a support to fish farms management and operations. It is implemented in an operational platform, which provides continuous information in real time as well as short term predictions. The deployed solution uses CMEMS physical products as an input data and offers to refine this solution in order to provide a local information on site using a downscaling strategy. High resolution satellite products and ocean modelling allow to include the impact of local coastal processes on currents and water quality parameters to provide a proper monitoring and forecasting solution at the scale of a specific fish farm.</p><p>To model specific eutrophication processes, a NPZD (Nutrients-Phytoplankton-Zooplankton-Detritus) biogeochemical model is used. Included in the MOHID Water modelling system, the water quality module (Mateus, 2006) considering 18 properties: nutrients and organic matter (nitrogen, phosphorus and silica biogeochemical cycles), oxygen and organisms (phytoplankton and zooplankton) was deployed in the western Aegean Sea. The simulated chlorophyll a concentrations are used to compute a risk level for the eutrophication occurrence. To complete this indicator, another risk level was based on the eutrophication variation following Primpas et al. (2010) formulation. In addition to model forecasts, ocean color observations from the Sentinel-2 MSI and Landsat-8 OLI sensors are used to provide high resolution chlorophyll a concentrations maps in case of bloom events. The processing chain uses the sixth version of the Quasi-Analytical Algorithm initially developed by Lee et al. (2002) and an empirical relation based on a database built using the HydroLight software to compute chlorophyll a concentration.</p><p>Two past eutrophication events monitored in situ (Varkitzi et al. 2018) were studied to assess the accuracy of the developed tool. Although few in situ data were available on environmental input (as rivers flow and nutrient concentrations), it was possible using statistics to reproduce qualitatively these blooms. Finally, an operational demonstration was conducted during 2 months of the 2020 autumn season, to showcase real time monitoring and predictive perspectives.</p>

Sign in / Sign up

Export Citation Format

Share Document