Rate of change of temperature of the gas.
An object of mass "m" specific heat "Cp" and surface area "As" is initially at a temperature "To". The object is heated by a gas stream which is at a constant temperature "To". The object is heated by a gas stream which is at a constant temperature "Tg" with a heat transfer coefficient "h". The heating process is described by the following heat balance.
Rate of Heat gained by Object = Rate of Heat Lost by Gas m, Cp, h, A and Tg are all constants.
1) prepare down the differential equation involving rate of increase of object temperature "T" with respect to time "t"
2) Resolve differential equation to produce and equation for "T" as a function of "t"