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+
+
+// Display mode
+mode(0);
+
+// Display warning for floating point exception
+ieee(1);
+
+clc;
+disp("Principles of Heat Transfer, 7th Ed. Frank Kreith et. al Chapter - 7 Example # 7.2 ")
+
+//Diameter of wire in m
+D = 0.000025;
+//Length of wire in m
+L = 0.006;
+//Free stream temperature of air in degeee C
+T = 20;
+//Wire temperature to be maintain in degree C
+Tw = 230;
+//Resistivity of platinum in ohm-cm
+Re = 0.0000171;
+
+//Since the wire is very thin, conduction along it can be neglected; also, the temperature gradient in the wire at any cross section can be disregarded.
+
+//At freestream temperature, for air:
+
+//Thermal conductivity in W/mC
+k = 0.0251;
+//Kinematic viscosity in m2/s
+nu = 0.0000157;
+
+//Reynolds number at velocity = 2m/s
+Rey = (2*D)/nu;
+if Re<40 then
+  //Using the correlation equa-tion from Eq. (7.3) and Table 7.1
+  //Average convection heat transfer coefficient as a function of velocity
+  //is
+  //hc=799U^0.4 W/m2C
+
+  //At this point, it is necessary to estimate the heat transfer coefficient for radiant heat flow.
+  //According to Eq. (1.21), we have approximately
+  //hr=sigma*epsilon*((Ts+Tinfinity)^3)/4
+
+  //The emissivity of polished platinum from Appendix 2, Table 7 is about 0.05, so hr is about 0.05 W/m2C.
+
+  //The rate at which heat is transferred from the wire is therefore
+  //0.0790U^4 W.
+
+  //The electrical resistance of the wire in ohm is
+  R = ((Re*L)*4)/(((100*%pi)*D)*D);
+end;
+
+//A heat balance with the current i gives
+disp("Current in ampere as a function of velocity is")
+disp("i=0.19*U^0.2")