A long counter-flow heat exchanger heats water from 15°C to 35°C by passing the water via the inner tube through an enclosure of hot air. The water is flowing through a 3.5-cm diameter tube at a rate of 0.3 kg/s. The air enters the enclosure at 80°C and exits at 30°C. 1536.7 W/m2K (a) Assuming the flow is fully developed, find out the convection coefficient of the water flow. (b) If the convection coefficient of air is 680 W/m².K, what is the length of the heat exchanger? 17.72 m Water Air

A long counter-flow heat exchanger heats water from 15°C to 35°C by passing the water via the inner tube through an enclosure of hot air. The water is flowing through a 3.5-cm diameter tube at a rate of 0.3 kg/s. The air enters the enclosure at 80°C and exits at 30°C. 1536.7 W/m2K (a) Assuming the flow is fully developed, find out the convection coefficient of the water flow. (b) If the convection coefficient of air is 680 W/m².K, what is the length of the heat exchanger? 17.72 m Water Air

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Related questions

Q: A heat exchanger is used to heat 3600 kg/h of water (c, 4.18 kJ/kg-°C) from 40°C to 175°C by cooling…

Q: erall heat transfer coefficient of the h

A: given:specific heat of water 4.18kj/kgkspecific heat of geothermal fluid=4.31kj/kgkmass flow of…

Q: 5000 kg of dry air per hour is cooled from 60 oC to 34 oC in a countercurrent heat exchanger. In the…

Q: shell-and-tube heat exchanger with 1-shell pass and 20–tube passes is used to heat glycerin (Cp =…

Q: Water enters at 20 C at a rate of 0.1 kg/s in a double-pipe counter flow heat exchanger is to be…

A: Given:Tci=20°Cmc=0.1 Kg/sThi=100°Cmh=0.3 Kg/sU=100 W/m2°CL=14 md=1.4 cmCpw=4.18 KJ/Kg°CCpa=1.01…

Q: lled purposely to cool us available at the rate

A: The heat transfer between two things is proportional to the temperature differential between them.…

Q: ater enters at 25 ℃ at a rate of 0.1 kg/s in a double-pipe counter flow heat exchanger is to be…

Q: A diesel engine produces hot exhaust gases which are used to produce steam in an evaporator. The…

Q: Glycerin (cp = 2400 J/kg⋅°C) at 20°C and 0.5 kg/s is to be heated by ethylene glycol (cp = 2500…

A: Cooling fluid:Tci = 20⁰Cmc = 0.5 kg/sCpc =  2400 J/kg⋅°Cheating fluid:Thi = 100⁰Cmh = 0.5 kg/sCpc =…

Q: Consider a double-pipe counter-flow heat exchanger. In order to enhance heat transfer, the length of…

A: The effectiveness of the heat exchanger mainly depends on the Number of Transfer Units (NTU). The…

Q: In a large air-conditioning application, 1500 m3/min of air at 1 atm and 10◦C are to be heated in a…

Q: The temperature difference between the hot and cold fluids in a heat exchanger is given to be ∆? at…

A: The symbols representing the temperature difference in the hot and cold fluids at each end are not…

Q: 23–78C Consider a shell-and-tube water-to-water heat ex- changer with identical mass flow rates for…

A: Write the initial case of mass flow rates of hot and cold water. m˙c=m˙h Write the expression of…

Q: n-walled, double-tube, counterflow heat exchanger is used to cool oil (Cp = 2.20 kJ/kg °C) from 150…

A: Given data as per question For Hot fluid , oil Cph=2.2 kJ/kg°C, Thi=150°C, Tho=40°C, m˙=2 kg/s For…

Q: Hot water at 60°C is cooled to 36°C through the tube side of a one-shell pass and two-tube passes…

A: It is required to determine the logarithmic mean temperature difference for counter flow. The…

Q: Water flows through a shower head steadily at the rate of 8 kg/min. The water is heated in an…

A: Given: mass flow rate of water = 8 kg/min = (8/60) kg/s = 0.133 kg/s initial cold water inlet, Tc1…

Q: A heat exchanger is used to heat cold water at 15°C entering at a rate of 2 kg/s with hot air at…

A: Given Data:

Q: What is application of parallel flow heat exchanger? and counter flow heat exchanger?

Q: In a heating process you need to rise the temperature of the orange juice (with mean specific heat…

Q: In a food processing plant, hot liquid water is being transported in a pipe (k = 15 W/m .K, D₁ = 2.5…

A: kpipe = 15 W/m.kDi = 2.5cm=0.025mDo= 3cm = 0.03mL = 10 mTi = 100oCTe = 60oCTe 45oCThe properties of…

Q: In order to cool a mass flow rate of 25 Kg/h of air (cp = 1060 J/Kg oC) at 300 oC, it is passed…

A: Hello. Since your question has multiple sub-parts, we will solve first three sub-parts for you. If…

Q: Fluid 1 flows at a speed of 700 kg/h from the inner tube of a double-pipe heat exchanger operating…

Q: n a place where the outdoor air temperature is 30°C, the air is compressed from its current…

A: Given , Inlet air temperature , T1 = 30 C = 303 K Outlet pressure , P2 = 800 KPa Flow rate of air ,…

Q: C- Hot engine oil is to be cooled in a double-tube counter-flow heat exchanger. The copper inner…

A: given water @ 52 c , 0.42 kg/s oil @ 95 c , 0.91 kg/s

Q: A parallel flow double-pipe heat exchanger is to heat water from 20°C to 90°C at a rate of 1.4 kg/s.…

Q: A counter-flow double-pipe heat exchanger is to heat water from 30°C to 80°C at a rate of 1.5 kg/s.…

Q: In order to cool a mass flow rate of 55 Kg/h of air (cp = 1060 J/KgoC) at 300o C, it is passed…

Q: Consider a shell-and-tube water-to-water heat exchanger with identical mass flow rates for both the…

A: Shell and tube heat exchanger Working fluid water Criteria for calculation is the mass flow rate of…

Q: Water enters at 20 ℃ at a rate of 0.1 kg/s in a double-pipe counter flow heat exchanger is to be…

A: Given:Twi=20°Cmw=0.1 Kg/sTai=90°Cma=0.3 Kg/sU=100 W/m2°CL=14 md=1.4 cmcw=4.18 KJ/Kg°Cca=1.01 KJ/Kg°C

Q: The air duct of the heating system of a hall consists of an electric heater placed inside and a 300…

A: Fan power: 300 WAir flow rate: 0.6 kg/sTemperature increase: 5°CHeat loss from duct surfaces to the…

Q: An exhaust valve has a valve curtain area of 3 x 10-3 m2 and valve discharge coefficient of 0.7.The…

Q: A stream of ammonia is cooled from 100oC to 20oC at a rate of 180 kg/hr in the tube side of a…

A: The inlet temperature of ammonia is .The exit temperature of ammonia is .The flow rate of ammonia is…

Q: Q14) A 65-kg beef carcass (k=0.47 W/m °C and a=0.13x10-6 m²/s) initially at a uniform temperature of…

A: velocity, v = 1.8 m/s

Q: A single-stage fluid with a mass flow rate of 2.5 kg / s and a heat capacity of 1800 j / kg-K is…

Q: Exhaust gas at 400°C and 1 bar from internal-combustion engines flows at the rate of 125 mol s¹ into…

A: Given Data

Q: One of the drawbacks for treating domestic wastewater in an activated sludge treatment is its…

A: Given: Flow rate of the wastewater →Q=6000 m3/d Because density of wastewater→ρ=1000 Kg/m3 Hence the…

Concept explainers

Heat Exchangers

Heat exchangers are the types of equipment that are primarily employed to transfer the thermal energy from one fluid to another, provided that one of the fluids should be at a higher thermal energy content than the other fluid.

Heat Exchanger

The heat exchanger is a combination of two words ''Heat'' and ''Exchanger''. It is a mechanical device that is used to exchange heat energy between two fluids.

Question

A long counter-flow heat exchanger heats water from 15°C to 35°C by passing the water via the inner
tube through an enclosure of hot air. The water is flowing through a 3.5-cm diameter tube at a rate
of 0.3 kg/s. The air enters the enclosure at 80°C and exits at 30°C.
1536.7 W/m2K
(a) Assuming the flow is fully developed, find out the convection coefficient of the water flow.
(b) If the convection coefficient of air is 680 W/m².K, what is the length of the heat exchanger?
17.72 m
Water
Air

Expert Solution

This question has been solved!

Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.

This is a popular solution!

SEE SOLUTION Check out a sample Q&A here

Step 1

Step 2

Step 3

Step 4

Trending now

This is a popular solution!

Step by step

Solved in 4 steps with 1 images

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.

Similar questions

Cold water (cp = 4180 J/kg×K) leading to a shower enters a thin-walled double-pipe counterflow heat exchanger at 15°C at a rate of 0.25 kg/s and is heated to 45°C by hot water (cp = 4190 J/kg×K) that enters at 100°C at a rate of 3 kg/s. If the overall heat transfer coefficient is 950 W/m2×K, determine the rate of heat transfer and the heat surface area of the heat exchanger using the effectiveness–NTU method.
Super heated steam
Water enters at 20 ℃ at a rate of 0.1 kg/s in a double-pipe counter flow heat exchanger is to be heated by hot air that enters the heat exchanger at 90 ℃ at a rate of 0.3 kg/s. The overall heat transfer coefficient based on the inner side of the tube to be 100 W/m2. ℃. The length of the tube is 14 m and the internal diameter of the tube is 1.4 cm. Determine the outlet temperature of the water. The specific heats of the water and air are given to be 4.18 and 1.01 kJ/kg.℃, respectively.Select one:a. 30.5 ℃b. 24.3 ℃c. 28.8 ℃d. 32.7 ℃
A long counter-flow heat exchanger cools water from 40°C to 10°C by passing the water via the inner tube through an enclosure of cold fluid. The water is flowing through a 3-cm diameter tube at a rate of 0.27 kg/s. The cold fluid enters the enclosure at −10°C and has a convection coefficient of 1200 W/m².K. The mass flow rate of the cold fluid and its specific heat are 1.2 kg/s and 1340 J/kg-K, respectively. (a) Assuming the flow is fully developed, find out the convection coefficient of the water flow. (b) What is the length of the heat exchanger? 1554 W/m²K 2 21.9m Water Cold Fluid
How does a heat exchanger work? Where and when will you use a heat exchanger?
A fruit juice is being heated in an indirect heat exchanger using steam as a heating medium. The product fl ows through the heat exchanger at a rate of 1500 kg/h and the inlet temperature is 20C. Determine the quantity of steam required to heat the product to 100C when only latent heat of vaporization (2200 kJ/kg) is used for heating. The specifi c heat of the product is 4 kJ/(kg C).
Water enters at 20 °C at a rate of 0.1 kg/s in a double-pipe counter flow heat exchanger is to be heated by hot air that enters the heat exchanger at 110 °C at a rate of 0.3 kg/s. The overall heat transfer coefficient based on the inner side of the tube to be 100 W/m2. °C. The length of the tube is 14 m, and the internal diameter of the tube is 1.4 cm. Determine the outlet temperature of the water. The specific heats of the water and air are given to be 4.18 and 1.01 kj/kg.°C, respectively. Select one: O a. 31.3 °C O b. 22.6 °C O C. 24.7 °C O d. 25.5 °C
Water enters at 20 ℃ at a rate of 0.1 kg/s in a double-pipe counter flow heat exchanger is to be heated by hot air that enters the heat exchanger at 90 ℃ at a rate of 0.3 kg/s. The overall heat transfer coefficient based on the inner side of the tube to be 100 W/m2. ℃. The length of the tube is 14 m and the internal diameter of the tube is 1.4 cm. Determine the outlet temperature of the air. The specific heats of the water and air are given to be 4.18 and 1.01 kJ/kg.℃, respectively. Select one: a. 82.6 ℃ b. 74.7 ℃ c. 72.5 ℃ d. 77.9 ℃
An adiabatic heat exchanger is used to heat cold water at 15°C entering at a rate of 5 kg/s with hot water at 90°C entering at a rate of 4 kg/s. If the exit temperature of hot water is 50°C, the exit temperature of cold water is (a) 42°C (b) 47°C (c) 55°C (d) 78°C (e) 90°C
In a facility, a counter-flow double-pipe heat exchanger is used to cool the fluid at a flow of 10.0 kg / s (Cp = 3.15 kJ / kgK) with an inlet temperature of 90 0C, and the surface area of the heat exchanger is As = 9 m2. The refrigerant (Cp = 4.2 kJ / kgK) enters the heat exchanger at a temperature of 10 ° C and a flow rate of 8.0 kg / h. Total heat transfer coefficient according to system data; ? = equation is given image. a) Calculate the heat transfer and heat exchanger exit temperatures.b) Existing heat exchanger is wanted to be changed. A seller offers an attractive discount to the plant authorities for two heat exchangers of the same property with a surface area of As = 5 m2. Since the pipe diameters in existing and new heat exchangers are the same, it is expected that the total heat transfer coefficient equation given above will also be valid for new heat exchangers. The vendor suggests that both heat exchangers can be operated in parallel in a counter-flow fashion, so that…
A thin-walled double-pipe counter-flow heat exchanger is to be used to cool oil (Cpo= 2200 J/kg.K) from 150°C to 40°C at a rate of 2 kg/s by water (Cpw= 4180 J/kg.K) that enters at 22°C at a rate of 1.5Kg/s. If the diameter of the tube is 2.5 cm, and its length is 6 m, determine * The rate of heat transfer in the heat exchanger * The outlet temperature of the cold fluid * The Log Mean Temperature Difference (LMTD) * The overall heat transfer coefficient
Steam at 1.6 MPa and 250°C is being throttled by an adiabatic steam valve to reduce its pressure to 0.5 MPa before it is being delivered to a heat exchanger (shown in Figure 1). At valve outlet, the steam at18,000 kg/hour flow into an adiabatic heat exchanger as hot fluid. Cooling water from water tap is used to cool the steam by circulating the water through the tubes inside the heat exchanger. At heat exchanger outlet, the cooling water temperature increased by 20°C as it passing through the heat exchanger, and steam leaves the heat exchanger as saturated vapor at 200 kPa. Determine: (a) the temperature of the steam at heat exchanger inlet; and (b) the mass flow rate of the cooling water required. (Note: Use specific heat of cooling water at constant pressure as 4.18 kJ/kg.C) Heat Exchanger Steam Steam valve Cooling Water