Brine flood in a 1.9-in-long and 1.5-in-diameter core plug from the north sea resulted in a stabilized pressure drop of 46.05 psi. the flood was carried out at 0.05 ml/min with brine viscosity of 0.443 cp. determine the absolute permeability of this plug in millidarcies.

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]