Question

Question 2. Answer all parts of this question a) A shell and tube heat exchanger is...

Question 2. Answer all parts of this question a) A shell and tube heat exchanger is to heat 10,000 kg h–1 of water from 16 to 84°C using hot oil entering at 160°C and leaving at 92°C. The oil will flow through the shell of the heat exchanger. The water will flow through 11 brass tubes of 22.9 mm inside diameter and 25.4 mm outside diameter, with thermal conductivity 137 W m–1 K–1, with each tube making two passes through the shell.

i) Using the Colburn Equation, given

Nu = 0.023Re0.8 Pr0.333 show that the convection heat transfer coefficient of the water flowing through the tubes is about 3300 W m–2 K–1. (Assume the density of water is 988 kg m–3 and find the other thermophysical properties of water from steam tables. Don’t forget to divide the total flowrate by the number of tubes to get the flowrate through each tube, in kg s–1.) [10 marks]

ii) The shell side heat transfer coefficient is 400 W m–2 K–1. Calculate the overall heat transfer coefficient based on the outside area of the tubes, assuming negligible fouling resistances. [4 marks] Answer: 351 W m–2 K–1

iii) Using the correction factor chart shown in Figure 2.1, determine the appropriate correction factor. [5 marks] Answer: 0.85

b) The oil in part (a) is pumped into the heat exchanger using a centrifugal pump. i) Power has dimensions of ML2T–3. Use dimensional analysis to derive a relationship between pumping power (P), fluid density ( ?), impeller diameter (D) and impeller rotational speed (N) of the form: P = K ? aNbDc [5 marks] Answer: P = K ? N 3 D

5 ii) A centrifugal pump is an example of a rotodynamic pump. Discuss the advantages and disadvantages of centrifugal pumps compared with positive displacement pumps. [6 marks]

Homework Answers

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A 1-shell-2-tube pass heat exchanger is made of a steel alloy (thermal conductivity 45.4 W/(m K)....
A 1-shell-2-tube pass heat exchanger is made of a steel alloy (thermal conductivity 45.4 W/(m K). It is used to cool distilled water from 34oC to 29oC using water which flows inside tubes with an outer diameter of 19 mm and an inner diameter of 16 mm. The number of tubes in the shell is 160 (80 per pass). The mass flow rate of distilled water in the shell is 76180 kg/h. The cold water enters the heat exchanger at...
A 1 to 2 baffled shell-and-tube type heat exchanger is used as an engine oil cooler....
A 1 to 2 baffled shell-and-tube type heat exchanger is used as an engine oil cooler. Cooling water flows through tubes at 25 °C at a rate of 8.16 kg/s and exits at 35 °C. The inlet and outlet temperatures of the engine oil are 65 and 55 °C, respectively. The heat exchanger has 12.25-in. I.D. shell, and 18 BWG and 0.75-in. O.D. tubes. A total of 160 tubes are laid out on a 15/16-in. triangular pitch. By assuming Ro...
Water at a flow rate of 60 kg/s enters the shell-side of a baffled shell-and-tube heat...
Water at a flow rate of 60 kg/s enters the shell-side of a baffled shell-and-tube heat exchanger at 35 °C and leaves at 25 °C. The heat will be transferred to 150 kg/s of raw water coming from a supply at 15 °C. You are requested to design the heat exchanger for this purpose. A single shell and single tube pass is preferable. The tube diameter is ¾ in. (19 mm outer diameter with 16 mm inner diameter) and tubes...
A shell and-tube heat exchanger is required for the following service: Hot stream Cold Stream Aromatic...
A shell and-tube heat exchanger is required for the following service: Hot stream Cold Stream Aromatic Stream Cooling Water inlet Temperature (oC) 85 20 outlet Temperature (oC) 40 35 Mass Flowrate x heat Capacity (kW/oC) 85.2 Hot Stream cold stream (Cooling water) Heat Capacity (J/kg K) 2840 4193 Density (kg/m3) 750 999 Viscosity (cP) 0.34 1.016 Thermal conductivity (W/m.K) 0.19 0.594 Fouling Factor (m2.oC/W 0.00018 0.000176 ? The cooling water is allocated to the tube-side of the exchanger. ? It...
A 1 shell pass, 4 tube pass shell-and-tube heat exchanger is used to cool therminol 59...
A 1 shell pass, 4 tube pass shell-and-tube heat exchanger is used to cool therminol 59 in a refinery. The therminol 59 enters the tubes at a mass flow rate of 0.87 kg/s and changes in temperature from 93◦C to 49◦C. Water is the other fluid. It enters the shell at a mass flow rate of 1.20 kg/s, and changes in temeperture from 23◦C to 37.1◦C. Determine the following: (a) (10 pts) The heat transfer between the two fluids (b)...
Hot oil at a rate of 5 kg/s (Cpm= 2 kJ/kg. K) enters in a 2-4...
Hot oil at a rate of 5 kg/s (Cpm= 2 kJ/kg. K) enters in a 2-4 shell and tube heat exchanger at 366 K and is cooled to 344 K by 2 kg/s of water (Cpm= 4 kJ/kg. K) entering at 283 K. The overall heat transfer coefficient U0 is 340 W/m . Calculate the area requied. If the length of each tube is 1.2 m, and the diameter of each tube is 0.1 m, calculate the number of tubes?
A horizontal shel-and-tube heat exchanger with two tube passes and one shell pass is being used...
A horizontal shel-and-tube heat exchanger with two tube passes and one shell pass is being used to heat 9 kg/s of 100% ethanol from 25 to 65 C at atmospheric pressure. The ethanol pasar through the inside of the tubes, and saturated steam at 115 C condenses an the shell of the tubes. The tubes are atell with an OD of 0.019 m and a BWG of 14. The exchanger contains a total of 100 tubes (50 tubes per pass)....
The condenser of a large steam power plant is a heat exchanger in which steam is...
The condenser of a large steam power plant is a heat exchanger in which steam is condensed to liquid water. Assume the condenser to be a parallel flow shell-and-tube heat exchanger consisting of a single shell and 10,000 tubes, each executing two passes. The tubes are of thin wall construction with D = 30 mm and the steam condenses on their outer surface. The heat transfer rate that must be effected by the exchanger is Q = 2 × 10^9...
A sugar solution (? = 1080 kg/m3, cp = 3601 J/kg ? K, kf = 0.5764...
A sugar solution (? = 1080 kg/m3, cp = 3601 J/kg ? K, kf = 0.5764 W/m ? K, ? = 1.3 × 10–3 N ? s/m2) flows at rate of 60,000 kg/hr and is to be heated from 25°C to 50°C. Water at 95°C is available at a flow rate of 75,000 kg/hr (cp = 4004 J/kg ? K). It is proposed to use a one shell pass and two tubes pass shell-and-tube heat exchanger containing 3/4 in. OD,...
A thin-walled double pipe counter flow heat exchanger is to be used to cool oil (cp...
A thin-walled double pipe counter flow heat exchanger is to be used to cool oil (cp = 2200 j/kg*K) from 150 ℃ to 30 ℃ at a rate of 2.1 kg/s by water (cp= 4180 J/kg*K) that enters at 20 ℃ at a rate of 1.2 kg/s. The diameter of the tube is 2.5 cm, and its length is 10 m. Using Excel (a) Determine the overall heat transfer coefficient of this heat exchanger. (b) Investigate the effects of oil...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT