Hot coolant water is supplied to a shell and tube heat-exchanger with two shells and twelve tube passes at rate of 1.5 kg/s and a temperature of 350°C. The heat exchanged is used to warm 2.6 kg/s of process water from 15°C to 125°C. Determine the required heat-transfer surface-area when the overall heat transfer coefficient is 1700 W/m-K. You may assume that the water pressure is sufficiently high so that no phase changes occur within the system and the water specific heat is constant at 4.18 kJ/kg.K. Answer: m?

Hot coolant water is supplied to a shell and tube heat-exchanger with two shells and twelve tube passes at rate of 1.5 kg/s and a temperature of 350°C. The heat exchanged is used to warm 2.6 kg/s of process water from 15°C to 125°C. Determine the required heat-transfer surface-area when the overall heat transfer coefficient is 1700 W/m-K. You may assume that the water pressure is sufficiently high so that no phase changes occur within the system and the water specific heat is constant at 4.18 kJ/kg.K. Answer: m?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.41P

See similar textbooks

Similar questions

Water flowing in a long, aluminum lube is to be heated by air flowing perpendicular to the exterior of the tube. The ID of the tube is 1.85 cm, and its OD is 2.3 cm. The mass flow rate of the water through the tube is 0.65kg/s, and the temperature of the water in the lube averages 30C. The free-stream velocity and ambient temperature of the air are 10m/sand120C, respectively. Estimate the overall heat transfer coefficient for the heat exchanger using appropriate correlations from previous chapters. State all your assumptions.
a one shell and two tube pass heat exchanger, coolant enters the tube at 4.81 kg/s (spread over 72 tubes with each tube being 0.01 m in diameter and 1.95 m length) at an initial temperature of 25 C. Water enters the shell at 2.5 kg/s at an initial temperature of 5 C. The average convection coefficient of the water is known to be 1e4 W/m2.K. What is the overall heat transfer coefficient, assuming no fouling, negligible tube thermal resistance and near-identical inner and outer tube surfaces? What is the actual heat transfer rate? What is the coolant outlet temperature? The coolant properties are Cp = 1040 J/kg.K, μ = 7.65e-4 kg/s.m, k = 0.058 W/m.K and Pr = 14. Assume the water Cp = 4200 J/kg.K.
Hot water at 90°C flows on the inside of a 2.5-cm-ID steel tube with 0.8-mm wall thickness at a velocity of 4 m/s. This tube forms the inside of a double-pipe heat exchanger. The outer pipe has a 3.75-cm ID, and engine oil at 20°C flows in the annular space at a velocity of 7 m/s. Calculate the overall heat-transfer coefficient for this arrangement. The tube length is 6.0 m.
Water is heated from 80°C to 150°C in a shell and tube heat exchanger with a total surface area of 824 m. Hot exhaust gases enter at 350°C and exit at 175°C, Determine the overall heat transfer coefficient (W/m".K) when the amount of heat transfer is 2.7 MJ? Use correction factor = 0.90 for heat exchanger.
F1 Vegetable oil at a flow rate of 10 kg/s (p=920 kg/m³; u=5x10-3 Pa.s; k=0.14 W/m K; cp-2.1 kj/kg K) from 51 pieces of 1.2 mm thick stainless steel plates It will be heated from 20°C to 50°C in a plate heat exchanger consisting of Heating will be carried out using steam at 121°C. The plate width (w) is 0.3 m and the clearance between the plates is 3 mm. The effective area is 1.5 times the projected area. The heat transfer coefficient for the steam side is 12000 W/m².K. Calculate the required plate length since the heat exchanger is operated in series flow order (Pressure drop must be determined)
100 kg/s of a crude oil is heated from 20°C to 40°C through the tube side of a multitube heat exchanger. The crude oil flow is divided evenly among all 100 tubes in the tube bundle. The ID of each tube is 10 mm, and the inside tubewall temperature is maintained at 100°C. Average properties of the crude oil are r = 950 kg/m3, cp = 1.9 kJ/kg?K, k = 0.25 W/m?K, m = 12 mPa?s, and mw = 4 mPa?s. Estimate the rate of heat transfer and the tube length.
5. Hot exhaust gases, which enter a finned-tube, cross-flow heat exchanger at 300 °C and leave at 100 °C, are used to heat pressurized water at a flow rate of 1 kg/s from 35 °C 125 °C. The specific heat of water at the average water temperature is 4197 J/kg. K. The overall heat transfer coefficient based on the gas-side surface area is U₁ = 100 W/m².K. Determine the required gas-side surface area A₁ using the LMTD and & -NTU method.
Water (cp = 4180 J/kg-K) enters the 2.5-cm internal-diameter %3D tube of a double-pipe counter-flow heat exchanger at 17°C at a rate of 1.8 kg/s. Water is heated by steam condensing at 120°C (hfg = 2203 kJ/kg) in the shell. If the overall heat transfer coefficient of the heat exchanger is 700 W/m2.K, determine the length of the tube required in order to heat the water to 80°c using: 7.1) the LMTD method. 7.2) the ɛ-NTU method.
A cylindrical heat exchanger is used to warm up a stream of 0.15 Kg s-l cold air from a temperature of 200 K to 300 K, after which it is released into the atmosphere. The air enters and leaves the heat exchanger through a pipe with a diameter of 5 cm. The heat exchanger is of a "Shell and tube design" as shown below and the air flows through the inside of the tubes. The internal diameter of the shell is 30 cm. There are 40 tubes each with a diameter of 1 cm in the heat exchange. It can be assumed that there is no friction in the system. The only change in the gas density occur inside the tubes, elsewhere, the gas can be considered incompressible. The density of the air at 300 K is 1.23 Kg m-3. The viscosity of air at 200 K is 1.1 x 10-5 kg m-l s-l; at 300 K it is 1.8 x10-5 kg m-! s-l. Water of enters the heat exchanger at 350 K and leaves at 320 K. a) Suggest suitable material for the tubes and shell for water to be sea water or feed water. b) Comment of the effect of fouling on the…
1Single-shell heat exchanger with two tube passes, water at 30°Cis used to cool 10 kg/s of nitrogen at 200°C at atmospheric pressure. Determine thenumber of tubes needed to cool the gas down to 90∘C while raising the temperature ofwater to 60°C using a 2 m long tube of 2 cm diameter. The overall heat transfer coefficientis 100 W/m#⋅ K. The values of specific heat for nitrogen and water are, 1045 J/kg ⋅ K and4180 J/kg ⋅ K,
Determine the length needed for a simple concentric-tube, parallel flow heat exchanger to transfer heat from hot water to cold water at a rate of 900 W. The heat exchanger consists of two Type K copper (k=386 W/m-degC) tubes. The smaller tube has an inside diameter of 49.8 mm and an outside diameter of 54.0 mm. Assume that both film coefficients are equal to 100 W/sq.m.-degC. The hot water enters at 90 degC and leaves at 50 degC, and the cold water enters at 10 degC and leaves at 40 degC.
2-b Hot exhaust gases, which enter a finned-tube, cross-flow heat exchanger at 300 °C and leave at 100 °C. are used to heat pressurized water at a flow rate of 1 kg/s from 35 °C to 125 °C. The specific heat of water at the average water temperature is 4197 J/kg. K. The overall heat transfers coefficient based on the gas-side surface area is Un = 100 W/m².K. Determine the required gas-side surface area A, using the LMTD and E-NTU method.