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3 years ago

Sketch the velocity profile for laminar and turbulent flow.

Engineering

1 answer:

Margarita [4]3 years ago

4 0

Answer:

The laminar flow is generally given in high viscosity fluids such as honey or oil, it has the characteristic of flowing in an orderly manner, the walls of the tube have a zero speed while in the center it has a maximum speed.

turbulent flow is characterized by fluid velocity vectors presenting themselves in a disorderly manner and in all directions.

I attached the drawings for the velocity profile in laminar and turbulent flow.

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True or false: You can create a network with two computers. Answer True

coldgirl [10]

To create a computer network, you must have at least two computers. ... A protocol is a standard set of rules and procedures for the control of communications in a network. TRUE. Two computers using TCP/IP can communicate even if they are based on different hardware and software platforms. So your right :)

Hope this helps :)

7 0

2 years ago

Read 2 more answers

A spark ignition engine burns a fuel of calorific value 45MJkg. It compresses the air-ful mixture in accordance with PV^1.3=cons

antoniya [11.8K]

Answer:

i). Compression ratio = 3.678

ii). fuel consumption = 0.4947 kg/hr

Explanation:

Given :

$PV^{1.3}=C$

Fuel calorific value = 45 MJ/kg

We know, engine efficiency is given by,

$\eta = 1-\left ( \frac{1}{r_{c}} \right )^{1.3-1}$

where $r_{c}$ is compression ratio = $\frac{v_{c}+v_{s}}{v_{c}}$

$r_{c}$ = $1+\frac{v_{s}}{v_{c}}$

where $v_{c}$ is compression volume

$v_{s}$ is swept volume

Now it is given that swept volume at 30% of compression, 70% of the swept volume remains.

Then, $v_{30}=v_{c}+0.7v_{s}$

and at 70% compression, 30% of the swept volume remains

∴ $v_{70}=v_{c}+0.3v_{s}$

We know,

$\frac{P_{2}}{P_{1}}=\left ( \frac{V_{1}}{V_{2}} \right )^{n}$

$\frac{2.75}{1.5}=\left ( \frac{v_{c}+0.7\times v_{s}}{v_{c}+0.3\times v_{s}} \right )^{1.3}$

$\left ( 1.833 \right )^{\frac{1}{1.3}}=\frac{v_{c}+0.7v_{s}}{v_{c}+0.3v_{s}}\\$

$1.594=\frac{v_{c}+0.7v_{s}}{v_{c}+0.3v_{s}}$

$v_{c}+0.7v_{s}=1.594v_{c}+0.4782v_{s}$

$0.7v_{s}-0.4782v_{s}=1.594v_{c}-v_{c}$

$0.2218v_{s} = 0.594v_{c}$

$v_{c}=0.3734 v_{s}$

∴ $r_{c}= 1+\frac{v_{s}}{0.3734v_{s}}$

Therefore, compression ratio is $r_{c}$ = 3.678

Now efficiency, $\eta =\left ( 1-\frac{1}{r_{c}} \right )^{0.3}$

$\eta =\left ( 1-\frac{1}{3.678} \right )^{0.3}$

$\eta =0.32342$ , this is the ideal efficiency

Therefore actual efficiency, $\eta_{act} =0.5\times \eta _{ideal}$

$\eta_{act} =0.5\times 0.32342$

$\eta_{act} =0.1617$

Therefore total power required = 1 kW x 3600 J

= 3600 kJ

∴ we know efficiency, $\eta=\frac{W_{net}}{Q_{supply}}$

$Q_{supply}=\frac{W_{net}}{\eta _{act}}$

$Q_{supply}=\frac{3600}{0.1617}$

$Q_{supply}=22261.78 kJ$

Therefore fuel required = $\frac{22261.78}{45000}$

= 0.4947 kg/hr

5 0

3 years ago

A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at 2308C by rejectin

lord [1]

Answer:

hello your question is incomplete attached below is the missing part and also attached is the solution

answer: a) 0.4801

b) 5.398 kw

c) 2.14

d) 12.72

Explanation:

The quality of the refrigerant at the evaporator inlet

h4 = hf4 + x4(hfx4)

Refrigeration load

Ql = m(h1-h4)

COP of the refrigerator

Ql / m(h2-h1) - Qm

Theoretical maximum refrigeration load

( Ql )max = COPr.rev * [m(h2-h1) - Qin]

5 0

3 years ago

You have removed a very large, thick plate of steel (AISI 1010) from your heat treat oven and have placed it on a large insulate

Andreas93 [3]

Answer:

for got sorry

Explanation:

6 0

3 years ago

When charging an R-410A system that uses a water-cooled condenser, you must first charge with vapor to a pressure of at least __

kirza4 [7]

Answer:

35psig

Explanation:

Pressure is a force that acts on a surface area. The psig measure the pressure pounds per square inch gauge. It measure the difference in pressure between supply tank and outside air. This pressure is relative to atmospheric pressure. When charging an R-410A system, the vapor pressure should be at least 35 psig before switching to liquid charging.

5 0

3 years ago