Concept explainers
A shell-and-tube heat exchanger with one shell passand 20 tube passes uses hot water on the tube side toheat oil on the shell side. The single copper tube hasinner and outer diameters of 20 and 24 mm and alength per pass of 3 m. The water enters at 87°C and0.2 kg/s and leaves at 27°C. Inlet and outlet temperatures of tile oil are 7 and 37°C. What is the averageconvection coefficient for the tube outer surface?
Want to see the full answer?
Check out a sample textbook solutionChapter 11 Solutions
Fundamentals of Heat and Mass Transfer
Additional Engineering Textbook Solutions
Vector Mechanics for Engineers: Statics and Dynamics
DeGarmo's Materials and Processes in Manufacturing
Automotive Technology: Principles, Diagnosis, and Service (5th Edition)
Thermodynamics: An Engineering Approach
Engineering Mechanics: Statics
Heating Ventilating and Air Conditioning: Analysis and Design
- 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.arrow_forwardWhat is the main difference between a copper and a cupronickel coaxial heat exchanger, and where is each used?arrow_forwardAn oil cooler is used to cool lubricating oil from 70oC to 40oC. The cooling water enters the heat exchanger at 15oC and leaves at 25oC. The specific heat capacities of the oil and water are 2000 and 4200 J/Kg.K respectively, and the oil flow rate is 4 Kg/s. Calculate the water flow rate required. Calculate the true mean temperature difference for (two-shell-pass / four-tube-pass) and (one-shell-pass / two-tube-pass) heat exchangers respectively. Find the effectiveness of the heat exchangers.arrow_forward
- A single-shell, four-tube-pass heat exchanger is used to cool water flowing at 14 kg.s¹ entering at 18°C using ammonia with a mass flow rate of 18 kg.s¹ and an entry temperature and pressure of -12°C and 650 kPa, absolute, respectively. The heat exchanger is to use the ammonia in the liquid form, so no evaporation can be allowed. At 620 kPa, absolute pressure, ammonia evaporates at 10.5°C. The overall heat transfer coefficient of the heat exchanger is 568 W.m2 and the heat transfer surface area is 75 m². Determine the outlet temperatures of the hot and cold streams. Identify whether the heat exchanger, operating under the conditions shown, satisfies the rec irement that the ammonia remains liquid throughout the process. Sources for any researched material properties must be properly referencedarrow_forwardThe shell fluid,ethylene glycol, enters at 120oC and leaves at 60oCwitha flow rate of 4000 kg/h. Water flows in the tubes, entering at 35oCand leaving at85oC. The overall heat-transfer coefficient for this arrangement is 900W/m2·oC.The exchanger is a shell tube with two shell passes and two tube passes.Calculate the following: a) The water exit temperature if flow rate of glycol to the exchanger is reduced in half with the entrance temperatures of both fluids remaining the same and by how much is the heat-transfer rate reduced?; b) The percentage reduction of heat transfer if water-flow rate is reduced by 25percent,while the gas flowrate is maintained constant along with the fluid inlet temperatures. Assume that the overall heat-transfer coefficient remains the same; andc) The flow rate of water required andthe area of the heat exchanger;arrow_forwardA two pass steam surface condenser is to be designed to condense 10000 kg/hr of steam having an enthalpy of 2240 kj/kg. Condenser pressure is 13.79 kpa. circulating water enters the condenser at 25 C and leaves at 40 C. the outside and inside diameter for a water tube, OD=20 mm, ID = 17 mm and water velocity of 3 m/s. if the overall coefficient of the heat transfer is 14100 kj/hr-m-C of outside tube surface, determine the amount of circulating water in m/hr.arrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage LearningRefrigeration and Air Conditioning Technology (Mi...Mechanical EngineeringISBN:9781305578296Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill JohnsonPublisher:Cengage Learning