I want to calculate the outlet sample flow rate coming out of a heat exchanger.I have 2 liquids (1 sample flow and 1 cooling water). Both liquids are water at saturationI know the specs for the cooling water:Flow Rate 30 gpmInlet Temp is 89 degrees FOutlet Temp is 115 degrees FLine size is 1 inch piping so an Inner diameter of 1.049 inchPressure 100 psigPipe is that of grounded steel/carbon steelI know most of the specs for Sample Flow:Inlet Temp 333 degrees FOutlet Temp 110 degrees FLine size is 3/8th inch tubing with an inner diameter of .245 inchPressure 1100 psigStainless Steel TubingThe heat exchanger is cross flow. Flow Rate I am expecting to be from .5 gpm to 2 gpm but I don't know how to calculate itWith all these known’s can you please help me calculate the sample flow rate or at least tell me the equations and process that I need to use and go about in solving it. Thank You
Assuming steady state and steady flow conditions, let these variables represent the the info Q=volume flow rate T=temperature m=mass V=velocity h=enthalpy v=specific volume=1/density (i)=inlet P=pressure (e)=exit first you need to calculate the velocities of both the sample and the cooling water flow using the equation V=Q/A where you substitute pi*radius^2 for the area A Applying the first law of thermodynamics with no height difference,and applying the continuity equation, it reduces to: h(e)+(V(e)^2)/2=h(i)+(V(i)^2)/2) you can substitute h=u+Pv where u is the internal energy (could be assumed zero)
Energy = (mass flow rate) (specific heat) (delta Temperature) Calculate the energy gained by the cooling water. It is equal to the energy lost by the coolant. Use the same formula and solve for sample flow rate.
