Question

(Heating Transfer)

- A wall with a heat transmission coefficient of 2 W / mK; thickness, width and height values are all 1 m (wall thickness 1 m and heat transfer area 1 mx 1 m = 1 m ^ 2) In the continuous regime, the relevant wall with inner surface temperature of 2000 K and outer surface temperature of 1000 K , unit Calculate the heat passing in time.

(Admissions: one dimensional heat conduction and constant heat conduction coefficient in the wall)

Answer #1

Given | |

1 | Heat transfer coefficent - k = 2 W /mK |

2 | Area of wall- heat transfer area = 1 m^2 |

3 | Thickness of wall - L = 1 m |

4 | Temperature of inner surface = T1 = 2000 K |

5 | Outer surface temperature = T2 = 1000K |

To find out Heat transfer -- | |

Ans | |

Heat transfer due to condution | |

Qcon = k A dT / L | |

= k A (T1-T2)/ L | |

= 2 x 1 x (2000-1000) / 1 | |

= 2 x 1 x 1000 | |

= 2000 Watt | |

Thus heat passing in time =
2000 Watt |

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