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Engineering maths

  • 20-04-2016 04:52PM
    #1
    Foodiescience
    Registered Users, Registered Users 2 Posts: 8 ✭


    Could someone please help me out with this question?

    Sugar solution is being heated by steam condensing at 3bar in a heat exchanger. The metal partition is stainless steel (k=21 x=1.6mm) the surface heat transfer coefficients for the condensing steam and the sugar solution are 12000 and 3000 wmk respectively. Calculate the mass of steam condensing per second if the area of heat transfer is 1.4m2 and the temperature of the sugar solution is 83c. Assume no sub cooling of condensate.


Comments

  • #2
    Pete67
    Registered Users, Registered Users 2 Posts: 1,257 ✭✭✭Pete67


    it's a question on heat transfer by conduction. Look up Fourier's Law. You will also need a set of steam tables.


  • #3
    Foodiescience
    Registered Users, Registered Users 2 Posts: 8 ✭Foodiescience


    Pete67 wrote: »
    it's a question on heat transfer by conduction. Look up Fourier's Law. You will also need a set of steam tables.

    Have steam tables converted the bar to celcius and then kelvin to get "delta T" problem is there are so many deravations of fouriers law of conduction I'm unsure which one I'm using or indeed what it is Im looking for am I to take "mass of steam condensing per second" to mean the rate of heat transfer or "q"


  • #4
    Pete67
    Registered Users, Registered Users 2 Posts: 1,257 ✭✭✭Pete67


    Yes, the mass of steam condensing per second can be related to the heat transfer Q by the specific enthalpy of evaporation (hfg) for saturated steam at 3bar, this figure can be found in the steam tables. The units are kJ/kg.


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