Question

P1:

A plate and frame heat exchanger is used to exchange heat in a
water-to-water flow system. Hot water enters the exchanger at 100 F
with a flow rate of 150 gpm. Cold water also enters at 150 gpm and
50 F.

The exchanger contains 25 plates, the spacing is 0.2 inches, the
plate material is 304SS (stainless steel), the plate thickness is .05 in, the plate
width is 15 in and the plate height is 3 ft.

Find the outlet temperature of both liquids for old and new heat
exchanger.

Answer #1

Hot water enters a counter-flow double-pipe heat exchanger at
180F with a velocity of 5 ft/s. Cold water at 80F flows at 3 ft/s
in the outer section of the exchanger. The diameter of the inner
pipe is 1 inch, the pipe wall thickness is 1/8", and the outer pipe
diameter is 2 inches. The overall heat transfer coefficient times
area per unit length UA/L = 150 Btu/hr-ft-F. If the exchanger is 16
feet long, what is the exit temperature...

Cold water enters a counter flow heat exchanger at 20ºC at a
rate of 10 kg/s, where it is heated by a hot water stream that
enters the heat exchanger at 80ºC at a rate of 2 kg/s. Assuming the
specific heat of water to remain constant at Cp=4.18 kJ/(kg.ºC),
determine the maximum heat transfer rate and the outlet
temperatures of the cold and the hot water streams.

Jack is operating a tubular, water-water heat exchanger when
suddenly, the valve controlling the flow rate of the hot-water
stream becomes stuck and he is now unable to adjust/control the
flow rate of the hot-water stream. Additionally, the tube providing
the hot water has become partially clogged, drastically reducing
the flow rate of hot water entering the exchanger. How could you
adjust the heat exchanger apparatus to maintain the same outlet
temperature of the cold-water stream as before the incident?...

A parallel flow heat exchanger is used to transfer heat from hot
water at 80oC, flowing at 5 L/min to cold water at
15oC which is flowing at a rate of 15 L/min. The overall
heat transfer coefficient is 2000 W/m2oC and the area is
0.2m2.
Calculate the heat transfer rate, the outlet temperature of the
cold water.

A thin-walled cross-flow heat exchanger is used to heat a
petrochemical whose specific heat is 1800 J (kg K)-1
with hot water (Cp = 4180 J (kg K)-1). The
petrochemical enters the heat exchanger at 20oC at a
rate of 3.7 kg s-1, whilst the water stream enters at
110oC at a rate of 2.5 kg s-1. The heat
transfer surface area of the heat exchanger is 4.8 m2
and the overall heat transfer coefficient is 940.30 W
m-2K-1. Determine...

In the heat exchanger, in theory, as the flow rate of the
cold-water stream increases, the outlet temperature of the
cold-water stream _________ .
Select one (1) of the following:
Stays the same
Decreases
Increases

An industrial facility needs a flow of 100 gpm of hot water at
180°F, 50 psia. Two designs are being considered to make the hot
water. In Design 1, the hot water is produced by injecting steam
into an insulated mixing chamber through which the water passes.
The water enters the chamber at 50°F, 50 psia. Steam is injected
into the chamber at 325°F, 50 psia. The hot water leaves at the
required flow rate and temperature. For this system...

Consider a counter-flow plate HX with channels of 12 in length,
6 in width, and 3/8 in thickness. The heat exchanger consists of
three flow channels with air at 200oC entering the center channel,
and air at 25oC entering the 2 outer channels, above and below the
center channel. The center channel has a flow rate of 3 x 10-4 m3/s
and the outer two channels have a flow rate of 1.67 x 10-4 m3/s in
each channel. The plates...

A concentric tube heat exchanger is comprised of a stainless
steel (ks = 40 W/mK) inner pipe, NPS 2- nominal schedule
40 size (corresponding to an inner diameter of 52.5 mm and an outer
diameter of 60.3 mm), and an outer stainless steel pipe of NPS
3-nominal schedule 40 (ID = 77.9 mm, OD = 88.9 mm). The heat
exchanger has an effective length of 35 m.
The inner pipe fluid is ammonia (?a = 0.3 · 10?6
m2/s, cpa...

A concentric tube heat exchanger is comprised of a stainless
steel (ks = 40 W/mK) inner pipe, NPS 2- nominal schedule
40 size (corresponding to an inner diameter of 52.5 mm and an outer
diameter of 60.3 mm), and an outer stainless steel pipe of NPS
3-nominal schedule 40 (ID = 77.9 mm, OD = 88.9 mm). The heat
exchanger has an effective length of 35 m.
The inner pipe fluid is ammonia (va = 0.3 ·
10-6m2/s, cpa =...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 5 minutes ago

asked 8 minutes ago

asked 11 minutes ago

asked 24 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago