to calculate alpha and beta
 

Hello,

I am modelling a Shell and tube heat exchanger shell side (1 Shell pass, 2 tube pass).I am modelling tubes as porous medium.Can any one help me in calculating alpha and beta values correctly?????

Thanks in advance

Re: to calculate alpha and beta
 

you need to get the pressure drop vs velocity data from somewhere (prob. expt) for the system. Then fit a second order polynomial in the data to get 'alpha and 'beta' as

y = alpha*x^2 + beta*x

where, y = pressure drop and x = velocity.