say i have a heat exchanger with a capacity of 100,000 BTU/hr.

 

and that steam will be the heating fluid, and oil will be the process fluid. i understand how to calculate for all my needed info for the process fluid. but i am not sure how to calculate the required info for the heating fluid (steam).

 

i want to be able to figure out how to make sure my heat exchanger is working at its full capacity, but i need to know how much steam i need to get into the system.

 

anybody have the needed equations for this?

well, do you have the pressure of the steam? is it superheated or saturated? if super heated, what temperature is it at? is there sub cooling of the condensate? if so, to what temperature do you cool it to?

 

once you know these it is a simple enthalpy balance.

One important question (as said by insane_alien) is whether you will get condensation or not. I think it's very common to have condensating steam in a heat exchanger (steam contains a massive amount of energy that can be transferred to the oil).

 

Condensating steam also makes it easier to solve your heat balance. The steam will condensate on the coldest part of the heat exchanger, which is the heat-exchanging-surface. You can also assume the temperature to be constant.

thanx guys, i have my answer now.

 

it was indeed condensing heat. and with the equation

Q=mass flow rate*latent heat of condensation

 

everything worked out fine.