Heat Release Rate Of A Subway Car On Fire In A Shrink-Scale Model

Heat release rate of a subway car on fire in a shrink-scale model

Abstract:
Heat release rate in a shrink-scale model of a subway car on fire is measured for various aspects of an ignition source and simulated materials differing in material by using shrink scale model. The time is required to reach the value, although the maximum Heat Release Rate value is independent of the position of the ignition source. The best method for determining the heat release rate is the maximum Heat Release Rate value and the material combustibility also has an effect. The heat release rate is compared with the fire test of a subway car.

Keywords: Subway Car, Shrink-Scale Model, Heat Release Rate.
Introduction:
The fire accidents in underground tunnels are
Reduced-Scale Model Test:
2.1. Froude Scaling

Froude scaling used for relation between an actual scale and reduced scale subway car. Protocol to full scale parameter estimates and by using the following equation, heat released rate in the reduced scale model is converted.
QR QM LR LM 5/2
Where Q is the heat release rate, L is the character length and subscripts R and M is the real and model respectively.
2.2.Shrink-Scale Subway Car
The shrink scale models of the dimensions are 1.9m in length, 0.29m in width and 0.235m in height. The actual train length is 19.7m. LM/LR is the reciprocal of the scale ratio. The train is stopped at the platform when a fire breaks out in a subway car, the sidewall near the platform will open for passenger. In the reduced scale model, all the four doors at the side wall were open and each door was 0.13m in width,0.18m in height and 0.024m in
Ignition Source
In the case 1, the first location between the seat and left end of the subway and the case 2, the second location between second door on the left and second seat on the left. In the case 3, the third location at the centre of the subway car. The heat release rate of the fire source used for the reduced scale model measured by 6 times by using cone diameter. During 300 s was 1kW is the average heat release rate.

2.4. Model Car materials To determine the combustibility of each interior material,3mm or 5mm thick plywood under incident heat fluxes of 10,20kW/m2 were measured by using ISO5660-compliant. Cone calorimeter and the large-scale calorimeter are used to measure the heat release rate from the reduced scale model and is calculated by measuring the amount of emitted flow and concentration of oxygen to quantify the consumption of oxygen by combustion.7mm thick and plywood 3mm or 5mmthick were used to the interior materials.

2.5 Model Measurements

In the reduced scale model subway car on fire to measure the heat release rate, the model is placed under the exhaust hood in the fire test room. It is collected by exhausted hood are mixed along the dust. The time lag in measurement is made up for comparing with the results of the standard propane burner and it can be obtained by measuring the mass loss rate, is measured by an electronic