Concept explainers
A novel heat exchanger concept consists of a largenumber of extruded polypropylene sheets
Want to see the full answer?
Check out a sample textbook solutionChapter 11 Solutions
Fundamentals of Heat and Mass Transfer
Additional Engineering Textbook Solutions
Thermodynamics: An Engineering Approach
Statics and Mechanics of Materials (5th Edition)
Fluid Mechanics Fundamentals And Applications
Automotive Technology: Principles, Diagnosis, and Service (5th Edition)
Engineering Mechanics: Statics
Vector Mechanics For Engineers
- 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_forwardYou are tasked to layout a cross-flow heat exchanger where both fluids remain unmixed. Unused engine oil is cooled at a flow rate of 3 kg/s. The oil enters the heat exchanger at 85.5°C and is cooled to 45°C. Water is used as the cooling medium at a flow rate of 2 kg/s, entering at 40°C and exiting at 60°C. The flow conditions in this heat exchanger yield the following convective heat transfer coefficients: h; = 8,000 W/m²/K and h, = 15,000 W/m²/K. Determine the following: 1. What is the area required to achieve the proposed performance? 2. During the design process it is recognized that the oil will cause fouling. The fouling coefficient is assumed to be 9.00*10-5 m²*K/W. How much larger will the area have to be to yield the same performance as in the clean state from part a?arrow_forwardWater is used in a heat exchanger to cool 5 kg/s of air from 400°C to 200°C. Calculate: A. The mass flow of water; B. The heat transfer rate to the water. 20°C WATER AIR AIR Heat Exchanger 400°C 200°C - 30°C WATERarrow_forward
- Single-shell, two-tube pass heat exchanger with surface area 0.4 m? and overall heat transfer coefficient of 1800 W/m2-K; saturated steam at 110°C condenses on one side while water at a flow rate of 0.35 kg/s enters at 17°C. Calculate (a) Outlet temperature of the water (b) Rate of condensation of steam. cp(water)=4179 J/kg. K. 916 I Thermodynamics TABLE A-4 Saturated water-Temperature table Internal energy, Specific volume, m/kg Enthalpy. KJ/kg Entropy, kJ/kg - K k/kg Sa. Sat Sat. Sat. Sat. Sat. Sat. Sat. liquid, Evap., vapor, Sat. Temp., liquid, liquid, Evap.. liquid, Evap., press. Pst kPa vapor, vapor, vapor, T°C Up he 0.001000 0.001000 0.000 21.019 42.020 2374.9 2374.9 0.001 21.020 42.022 0.0000 9.1556 9.1556 0.0763 0.1511 8.7488 8.8999 0.2245 8.5559 8.7803 0.2965 8.3696 8.6661 0.01 5 10 0.6117 0.8725 1.2281 206.00 147.03 106.32 2360.8 2346.6 2381.8 2388.7 2500.9 2489.1 2477.2 2500.9 2510.1 2519.2 8.9487 9.0249 15 20 0.001000 0.001001 2.3392 0.001002 2332.5 2318.4 2395.5 2402.3…arrow_forward5. 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 Uh = 100 W/m².K. Determine the required gas-side surface area A₁ using the LMTD and & -NTU method.arrow_forwardA counter-flow heat exchanger is designed to heat a fuel oil from 45°C to 100°C while the heating fluid enters at 150°C and leaves at 115°C. Calculate the arithmetic mean temperature difference. Badly needed asap. I will rate helpful. Thank you in advance.arrow_forward
- I need the solution in hand writingarrow_forward1. A crossflow heat exchanger, one fluid mixed and one unmixed (oil in tubes and steam in shell), is used to heat an oil in the tubes (c = 1.9 kJ/kg°C) from 15°C to 85°C. Steam (5.2 kg/s, c = 1.86 kJ/kg°C) blows across the outside of the tube, enters at 130°C and leaves at 110°C. U. = 275 W/m²K. Calculate A. [10.84 m²]arrow_forwardNanofluids are at the spot of consideration for new generation of heat exchangers. As a process engineer working at solar power system, you were assigned to design a novel heat exchanger and you was advised to use nanofluids. Which nanofluid you will use? What are the expected heat transfer enhancement? what are the expected challenges?arrow_forward
- The thermal conductivity of aluminum is higher than that of concrete material (one of most popular building materials). Select one: O True O False An example of convective heat transfer is freezing of the ground during the winter. Select one: O True O False Fouling on heat exchanger tubes has no effect on heat exchanger's performances. Select one: O True O False For good winter jackets, they should be made of light-weight materials, filled with air, that have very low conductivity. Select one: O True O Falsearrow_forwardpart darrow_forwardanswer question (B) onlyarrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning