A long concrete beam is to undergo a thermal test to determine its loss of strength in the event of a building fire. The beam cross section is triangular as shown in the sketch. Initially, the beam is at a uniform temperature of 20?C. At the start of the test, one of the short faces and the long face are exposed to hot gases at 400?C through a heat transfer coefficient of 10 W/(m2 K) and the remaining short face is adiabatic. Produce a graph showing the highest and lowest temperatures in the beam as a function of time for the first 1 hour of exposure. For the concrete properties, use k = 0.5 W/(mK) and n = 5 10??7 m2/s. Use a node spacing of 4 cm. and use an explicit difference scheme.GIVENConcrete beam suddenly exposed to hotgases

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Insulated t> 0: T.=400°C, h= 10W/(m? K) -Concrete Beam Crosa-eection 3 |-1 t> 0: T.-400°C, h- 10 W/(m2 K) I-1 2 3 4 5 6 20 cm Problem Defintion Sketch Node and Control Volume Layout 20 cm