Question

9-162

Write a computer program with ESS to evaluate the variation of temperature with time of thin square metal plate that are removed from an oven at a specified temperature and placed vertically in a large room. The thickness the size, the initial temperature, the emissivity, the thermophysical properties of the plate as well as the room temperature are to be specified by the user. The program should evaluate the temperature of the plate at specified intervals and tabulate the result against time. The computer should list the assumptions made during calculations before printing the results.

For each step or time interval, assume the surface temperature to be constant and evaluate the heat loss during that time interval and the temperature drop of the plate as a result of this heat loss. This gives the temperature of the plate at the end of a time interval, which is to serve as the initial temperature of the plate for the beginning of the next time interval.

Try your program for 0.2 cm-thick vertical copper plates of 40 cm x 40 cm in size initially at 300oC cooled in a room at 25oC. Take the surface emissivity to be 0.9. Use a time interval of 1s in calculations, but print the results at 10-s interval for a total cooling period of 15 min.

Answer 1

Answer:-

The below is the required source code for the given problem using C++

Code:-

#include <iostream>
#include <math.h>
using namespace std;

int main()
{
int l,h;
double b, initTemp,emissivity;
double roomTemp;
cout<<endl<<"Enter the details of Square metal plates";
cout<<endl<<"Thickness: ";
cin>>b;
cout<<endl<<"Size (length, height): ";
cin>>l;
cin>>h;
cout<<"Initial temperature: ";
cin>>initTemp;
cout<<endl<<"Emissivity: ";
cin>>emissivity;
cout<<endl<<"Enter room temperature: ";
cin>>roomTemp;
double heatLoss;
double tempDrop;
double Ts=initTemp;
cout<<endl<<"Time interval \t HeatLoss \t temperature drop"<<endl;
for(int t=15;t<150;t+=15)
{
heatLoss=emissivity*5.67*exp(-1*8)*t*(l*b*h)*pow(roomTemp-Ts,4);
tempDrop=initTemp-heatLoss;
Ts-=roomTemp-tempDrop;
cout<<t<<" \t "<<heatLoss<<" \t "<<tempDrop<<endl;
}
return 0;
}