Dear Ahmed Vawda
You do not need to worry too much as the system you describe is self balancing on the syrup side assuming a "clean" syrup, and a generous supply of low viscosity cooling medium. Consider this: If one HE (heat exchanger) is cooling more than the other then the product viscosity, and therefore the pressure drop will increase. This means the syrup flow will seek the hotter HE. As the flow through the hotter HE increases, the heat transfer coefficient will increase and cooling will be increased. By regulating the cooling fluid flow according to exit temperature, it will be easy to keep the system balanced. If you take care in arranging the inlet and outlet pipework for both fluid streams to have equal resistance, then I doubt that you would need any form of automatic control. Remember that each HE, I assume (plate or through tube), has a series of parallel flow channels. By having two HE units, you are merely doubling the number of parallel paths. Allow for thermometers plus a regulating valve on the outlet stream of each HE plus careful pipework to give both HEs equal flow. If the price of the extra equipment still favours the two HEs then I would say go with it.
Cheers
Steve McKenzie
-----Original Message-----
From: Ahmed Vawda [mailto:avawda@aksugar.co.ae]
Sent: Saturday, November 16, 2002 10:32 PM
To: 'PipingDesign@yahoogroups.com'
Subject: [PipingDesign] Splitting Flow Equally
Dear Forum Members
I am planning to buy a heat exchanger to cool hot syrup. The problem is that the price of two smaller units is cheaper than the price of one large unit. Besides the price, the pressure drop in the large unit is greater than that in the two smaller units. How can I distribute the flow equally, without the use of expensive flow measurement devices?
Ahmed Vawda
Process Engineer
Al Khaleej Sugar Dubai
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Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ Received on Sat Nov 16 05:34:00 2002
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