scholarly journals Activation Conditions of Sprinkler Head Considering Fire Growth Scenario

2020 ◽  
Vol 34 (4) ◽  
pp. 45-51
Author(s):  
Sung-Chan Kim
Keyword(s):  
Thermal Response ◽  
Fast Response ◽  
Standard Test ◽  
Fire Growth ◽  
Gas Temperature ◽  
Sensing Element ◽  
Maximum Heat ◽  
Test Conditions ◽  
Sprinkler Head ◽  
Growth Scenario

The aim of this study is to investigate the gas temperature and velocity during sprinkler activation considering the fire growth scenario based on the thermal response model of the sprinkler. The fire source is assumed to have time square fire growth scenarios with a maximum heat release rate of 3 MW. Eight types of standard and fast-response sprinkler heads with an operating temperature range of 65–105 ℃ and a response time index range of 25–171 m<sup>1/2</sup>s<sup>1/2</sup> were adopted. The temperature difference between the gas stream and the sensing element of the sprinkler head decreased as the fire growth slowed down, and the RTI value decreased. The overall gas temperature and velocity conditions predicted using the FDS model at sprinkler activation were in reasonable agreement with those of standard test conditions of the sprinkler head response. However, the sprinkler head could be activated at lower limits of gas temperature and velocity under the current test conditions for a slowly growing fire scenario.

Fire Growth in Standard Tests and Railcars

2018 ◽  
Author(s):  
Charles Luo ◽  
Soroush Yazdani ◽  
Brian Y. Lattimer
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Large Scale ◽  
Growth Conditions ◽  
Standard Test ◽  
Fire Growth ◽  
Gas Temperature ◽  
Fire Dynamics ◽  
Room Corner Test

Large scale flammability performance of interior finish used on railcars has been evaluated in previous studies using the NFPA 286 room corner fire test, which has a cross-section similar to a railcar. In some studies, the wall containing the door was removed to account for the shorter length of the room compared to the railcar length. The focus of this study is to assess whether the NFPA 286 standard room-corner test with a door represents conditions that developed inside a railcar during a fire. Fire Dynamics Simulator (FDS) was used to model the fire growth in a NFPA 286 standard room-corner test with a door, NFPA 286 room without the wall containing the door, and railcar geometry with a single door open. All three cases had the same exposure fire in a corner and the same lining material. In predictions of the NFPA 286 room-corner test with a door, gas temperature, heat release rate, and time to flashover agreed well with available NFPA 286 standard test data. The simulation results of fire growth inside a railcar with one side door open produced similar conditions and fire growth compared with the standard NFPA 286 room with a door. For simulations on the NFPA 286 room with the wall containing the door removed, it was found that removal of the wall with the door resulted in non-conservative fire growth conditions with the gas temperature and heat release rate under-estimated compared to the standard NFPA 286 room with a door. These simulations indicate that the standard NFPA 286 room-corner test with a door is representative of conditions that would develop inside of a railcar.

Effect of Compression and Expansion on Instantaneous Heat Transfer in Reciprocating Internal Combustion Engines

1987 ◽  
Vol 201 (3) ◽  
pp. 175-186 ◽  
Author(s):  
B Lawton
Keyword(s):  
Heat Flux ◽  
Internal Combustion Engines ◽  
Fast Response ◽  
Gas Temperature ◽  
Maximum Heat ◽  
Simple Modification ◽  
Maximum Heat Flux ◽  
Volumetric Rate ◽  
Compression And Expansion ◽  
Surface Thermocouple

Instantaneous heat flux at the surface of a cylinder head in a motored diesel engine has been measured, at various speeds, using a fast-response surface thermocouple. Heat flux during compression was found to be much larger than heat flux during expansion, the maximum heat flux occurred about 8° before top dead centre and there was a significant heat flux even when gas temperature and wall temperature were equal. During expansion, heat flowed from the surface to the gas even though the bulk gas temperature was greater than the surface temperature. These effects are predicted by solutions of the equation of thermal energy and are shown to be related to the volumetric rate of compression or expansion. A simple modification of Annand's equation gives good results and is recommended for general cycle calculations.

Measurement of Noise inside the Compartment and Vibration on both Sides of Elastomeric Powertrain Mounts of Passenger Car

2013 ◽  
Vol 471 ◽  
pp. 59-63
Author(s):  
Mohd Noor Arib Rejab ◽  
Roslan Abd Rahman ◽  
Raja Ishak Raja Hamzah ◽  
Jawaid Iqbal Inayat Hussain ◽  
Nazirah Ahmad ◽  
...  
Keyword(s):  
Fast Response ◽  
Sound Level ◽  
Measurement Noise ◽  
The Other ◽  
Vibration Level ◽  
Test Conditions ◽  
Exhaust Noise ◽  
Run Up ◽  
Level Meter ◽  
High Level

This paper presents an evaluation on elastomeric mount used to isolate vibration from powertrain to chassis or structure vehicle. The assessments started with measurement of noise inside compartment, and exhaust noise. This is followed by the measurement of vibration on both sides of elastomeric mounts. The noise in the compartment and exhaust noise is measured according to BS 6086: 1981 and BS ISO 5130: 2007. The noise in the compartment and vibration is tested in three conditions. Firstly, engine is run-up with load (driving at second gear); secondly, without load; and thirdly, without load but hanging. A microphone is fixed at the ear of the mannequin. The fast response and A weighting sound level meter were used for measurement noise in the compartment and exhaust noise. The vibration is measured in terms of acceleration on both sides of each elastomeric powertrain mounts. Two accelerometer transducers are fixed on both sides of powertrain elastomeric mounts. One side was identified as a source of vibration and the other as receiver of vibrations. The results showed that the pattern of overall vibration level on source and receiver increased from 1050 RPM (idling) to 4000 RPM on all test conditions. Vibration transmitted to chassis or receiver structure was analyzed using transmissibility concept. By evaluating test condition of engine run-up without load, informed that the front and rear mounts showed a high level transmissibility contributing to structure-borne noise.

A Fiber Optic Probe for Gas Total Temperature Measurement in Turbomachinery

1995 ◽  
Vol 117 (4) ◽  
pp. 635-641 ◽  
Author(s):  
S. R. Kidd ◽  
J. S. Barton ◽  
P. Meredith ◽  
J. D. C. Jones ◽  
M. A. Cherrett ◽  
...  
Keyword(s):  
Fiber Optics ◽  
High Speed ◽  
Gas Temperature ◽  
Fiber Optic Probe ◽  
Sensing Element ◽  
Unsteady Temperature ◽  
High Bandwidth ◽  
New Type ◽  
Total Temperature ◽  
Optic Probe

This paper describes the design, operation, construction, and demonstration of a new type of high-bandwidth unsteady temperature sensor based on fiber optics, and capable of operating in a high-speed multistage research compressor with flow representative of jet engine conditions. The sensing element is an optical coating of zinc selenide deposited on the end of an optical fiber. During evaluation in aerodynamic testing, a 1 K gas temperature resolution was demonstrated at 9.6 kHz and an upper bandwidth limit of 36 kHz achieved.

scholarly journals An Improved Generalized Method for Evaluation of Parameters, Modeling, and Simulation of Photovoltaic Modules

2017 ◽  
Vol 2017 ◽  
pp. 1-19 ◽  
Author(s):  
Vandana Jha ◽  
Uday Shankar Triar
Keyword(s):  
Modeling And Simulation ◽  
Standard Test ◽  
Unknown Parameters ◽  
Photovoltaic Modules ◽  
Pv Module ◽  
Test Conditions ◽  
Pv Modules ◽  
Evaluation Of Parameters ◽  
Output Characteristics ◽  
Matlab Programming

This paper proposes an improved generalized method for evaluation of parameters, modeling, and simulation of photovoltaic modules. A new concept “Level of Improvement” has been proposed for evaluating unknown parameters of the nonlinear I-V equation of the single-diode model of PV module at any environmental condition, taking the manufacturer-specified data at Standard Test Conditions as inputs. The main contribution of the new concept is the improvement in the accuracy of values of evaluated parameters up to various levels and is based on mathematical equations of PV modules. The proposed evaluating method is implemented by MATLAB programming and, for demonstration, by using the values of parameters of the I-V equation obtained from programming results, a PV module model is build with MATLAB. The parameters evaluated by the proposed technique are validated with the datasheet values of six different commercially available PV modules (thin film, monocrystalline, and polycrystalline) at Standard Test Conditions and Nominal Operating Cell Temperature Conditions. The module output characteristics generated by the proposed method are validated with experimental data of FS-270 PV module. The effects of variation of ideality factor and resistances on output characteristics are also studied. The superiority of the proposed technique is proved.

scholarly journals Performance Evaluation of Analytical Methods for Parameters Extraction of Photovoltaic Generators

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4825 ◽  
Author(s):  
Nader Anani ◽  
Haider Ibrahim
Keyword(s):  
Performance Evaluation ◽  
Computational Complexity ◽  
Numerical Methods ◽  
Analytical Methods ◽  
Standard Test ◽  
Pv Module ◽  
Test Conditions ◽  
Parameters Extraction ◽  
Detailed Mathematical Analysis ◽  
Photovoltaic Generators

This paper presents a succinct exploration of several analytical methods for extracting the parameters of the single-diode model (SDM) of a photovoltaic (PV) module under standard test conditions (STC). The paper investigates six methods and presents the detailed mathematical analysis leading to the development of each method. To evaluate the performance of these methods, MATLAB-based software has been devised and deployed to generate the results of each method when used to extract the SDM parameters of various PV test modules of different PV technologies. Similar software has also been developed to extract the same parameters using well-established numerical and iterative techniques. A comparison is subsequently made between the synthesized results and those obtained using numerical and iterative methods. The comparison indicates that although analytical methods may involve a significant amount of approximations, their accuracy can be comparable to that of their numerical and iterative counterparts, with the added advantage of a significant reduction in computational complexity, and without the initialization and convergence difficulties, which are normally associated with numerical methods.

Standard Characterization of Multi-junction Thin-film Photovoltaic Modules: Spectral Mismatch Correction to Standard Test Conditions and Comparison with Outdoor Measurements

2010 ◽  
Vol 1245 ◽  
Author(s):  
Mauro Pravettoni ◽  
Georgios Tzamalis ◽  
Komlan Anika ◽  
Davide Polverini ◽  
Harald Müllejans
Keyword(s):  
Thin Film ◽  
Spectral Response ◽  
Standard Test ◽  
Large Area ◽  
Response Measurement ◽  
Test Conditions ◽  
Current Voltage ◽  
Long Term Performance ◽  
Term Performance

AbstractMulti-junction thin-film devices have emerged as very promising PV materials due to reduced cost, manufacturing ease, efficiency and long term performance. The consequent growing interest of the PV community has lead to the development of new methods for the correction of indoor measurements to standard test conditions (STC), as presented in this paper. The experimental setup for spectral response measurement of multi-junction large-area thin-film modules is presented. A method for reliable corrections of indoor current-voltage characterization to STC is presented: results are compared with outdoor measurements where irradiance conditions are close to standard ones, highlighting ongoing challenges in standard characterization of such devices.

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