A double-pipe heat exchanger is made up from an interior thick-tube (k = 110 W/m K) with internal and external diameters of 1.3 cm and 1.5 cm, respectively, and an exterior tube with diameter of 3 cm. A fouling layer with Ro= 0.0004 m2 K/W has formed on the outer surface of the interior tube. Assume the length of this heat exchange is 1 m and use the following flow and fluid properties: Inlet um Ti To Ср [m/s] [°C] [°C] [kg/m³] (W/m'.K] [J/kg.K] Hot fluid (External flow) Cold fluid 0.014 125 854 267 2118 ----- -- 0.03 20 60 1000 11717 4180 (Internal flow) Determine the followings: The thermal resistance due to wall conduction. The convection thermal resistance of the internal flow. The convection thermal resistance of the external flow. The thermal resistance due to fouling in K/W. The log-mean temperature difference, ATIM-

In a chemical plant a solution of density 1100 kg/m' and specific heat capacity 4.6 kJ/kg K is to be heated from 65 "C to 100 "C; the required flow rate of solution is 11.8 kg/s. It is desired to use a tubular heat exchanger, the solution flowing at about 1.2 m/s in 25 mm bore iron tubes, and being heated by wet steam at 115°C. The length of the tubes must not exceed 3.5 m. Taking the inside and outside heat transfer coefficients as 5 and 10 kW/m K, and neglecting the thermal resistance of the tube wall, estimate the number of tubes and the number of tube passes required. 16.25

An incompressible fluid flows through a rectangular cross section duct, with width much larger than height of the cross section. The duct surface is heated at a uniform rate along its length. If the centreline of the flow is along the centre of the duct where y = 0, the distance from the centreline to the surface of the duct is b = 25 mm, and the thermal conductivity of the fluid is 0.6 W/mK, what is the local heat transfer coefficient in the developed region of the flow? Give your answer in W/m2K to 1 decimal place.  I AM POSTIING THIS AGAIN. PLEASE STOP ? COPY FROM INTERNET AND SEND RANDOM SOLUTION. HINT THE FINAL  ANSWER IS 38.4 But i need step by step solution.  if you don't get this value don't send it please, reject and add the credit

What is the heat capacity rate? What can you say about the temperature changes of the hot and cold fluids in a heat exchanger if both fluids have the same capacity rate? What does a heat capacity of infinity for a fluid in a heat exchanger mean?

A two-fluid heat exchanger has inlet and outlet temperatures of 65 and 40°C for the hot fluid and 15 and 30°C for the cold fluid. Can you tell whether this exchanger is operating under counterflow or parallel-flow conditions? Determine the effectiveness of the heat exchanger.

Water enters at 20 ℃ at a rate of 0.2 kg/s in a double-pipe parallel flow heat exchanger is to be heated to 70 ℃ by geothermal water that enters the heat exchanger at 155 ℃ at a rate of 0.3 kg/s. The overall heat transfer coefficient of the heat exchanger is 500 W/m2. ℃. The internal diameter of the tube is 1.2 cm. Determine the length of the heat exchanger. The specific heats of the water and geothermal water are given to be 4.18 and 4.31 kJ/kg.℃, respectively. Select one: a. 25.4 m b. 30.5 m c. 20.7 m d. 27.5 m

A refrigerant 22 condenser has four water passes and a total of 60 copper tubes that are 14 mm ID and have 2 mm wall thickness. The conductivity of copper is 3 90 W/m • K. The outside of the tubes is finned so that the ratio of outside to inside area is 1.7. The cooling-water flow through the condenser tubes is 3.8 L/s (a) Calculate the water-side coefficient if the water is at an average temperature of 30°C, at which temperature k = 0.614 W/m • K, p = 996 kg/m3 , andµ= 0.000803 Pa• s (b) Using a mean condensing coefficient of 1420 W/m2 • K, calculate the overall heat-transfer coefficient based on the condensing area.

The condenser of a large thermal power plant is a body-tube type heat exchanger consisting of a single body and 30000 pipes with two passes each. The pipes are thin-walled with an inner diameter of 25 mm, and steam condenses on the outer surfaces of the pipes with a convection coefficient of 11000 W / m2.K. The heat transfer required by the heat exchanger is 2000 MW, and it is provided by the flow of water through the pipes at a flow rate of 30000 kg / h. Water enters at 20 ° C, steam condenses at 50 ° C. Calculate the temperature of the cooling water leaving the condenser? Determine the required pipe length per pass? The properties of water at Tort = 300 K; Cp = 4180 j / kgK, μ = 855 × 10--6 Ns / m2, k = 0.613 W / mK, Pr = 5.83.

A single-pass, cross-flow heat exchanger uses hot exhaust gases (mixed) to heat water (unmixed) from 30 to 70 °C at a rate of 3 kg/s. The exhaust gases, having thermophysical properties similar to air, enter and exit the exchanger at 200 and 100 °C, respectively. If the overall heat transfer coefficient is 200 W/m2 ·K, estimate the required surface area. Hint : from 30 to 70 °C at a rate of 3 kg/s.

I am reviewing methods of assessing systems in heat transfer. One of the method I have run across for looking at single pass heat exchangers is log mean temperature difference (LMTD). What is the advantage of using LMTD instead of the basic/arithmetic difference in temperatures?