Strands of materials A and B are placed under a tensile force of 10 Newtons. Material A deforms more than Material B.

Air enters the compressor of a cold air-standard Brayton cycle with regeneration and reheat at 100 kPa, 300 K, with a mass flow

yanalaym [24]

Answer:

a. 47.48%

b. 35.58%

c. 2957.715 KW

Explanation:

$T_2 =T_1 + \dfrac{T_{2s} - T_1}{\eta _c}$

T₁ = 300 K

$\dfrac{T_{2s}}{T_1} = \left( \dfrac{P_{2}}{P_1} \right)^{\dfrac{k-1}{k} }$

$T_{2s} = 300 \times (10) ^{\dfrac{0.4}{1.4} }$

$T_{2s}$ = 579.21 K

T₂ = 300+ (579.21 - 300)/0.8 = 649.01 K

T₃ = T₂ + $\epsilon _{regen}$ (T₅ - T₂)

T₄ = 1400 K

Given that the pressure ratios across each turbine stage are equal, we have;

$\dfrac{T_{5s}}{T_4} = \left( \dfrac{P_{5}}{P_4} \right)^{\dfrac{k-1}{k} }$

$T_{5s}$ = 1400× $\left( 1/\sqrt{10} \right)^{\dfrac{0.4}{1.4} }$ = 1007.6 K

T₅ = T₄ + ( $T_{5s}$ - T₄)/ $\eta _t$ = 1400 + (1007.6- 1400)/0.8 = 909.5 K

T₃ = T₂ + $\epsilon _{regen}$ (T₅ - T₂)

T₃ = 649.01 + 0.8*(909.5 - 649.01 ) = 857.402 K

T₆ = 1400 K

$\dfrac{T_{7s}}{T_6} = \left( \dfrac{P_{7}}{P_6} \right)^{\dfrac{k-1}{k} }$

$T_{7s}$ = 1400× $\left( 1/\sqrt{10} \right)^{\dfrac{0.4}{1.4} }$ = 1007.6 K

T₇ = T₆ + ( $T_{7s}$ - T₆)/ $\eta _t$ = 1400 + (1007.6 - 1400)/0.8 = 909.5 K

a. $W_{net \ out}$ = cp(T₆ -T₇) = 1.005 * (1400 - 909.5) = 492.9525 KJ/kg

Heat supplied is given by the relation

cp(T₄ - T₃) + cp(T₆ - T₅) = 1.005*((1400 - 857.402) + (1400 - 909.5)) = 1038.26349 kJ/kg

Thermal efficiency of the cycle = (Net work output)/(Heat supplied)

Thermal efficiency of the cycle = (492.9525 )/(1038.26349 ) =0.4748 = 47.48%

b. $bwr = \dfrac{W_{c,in}}{W_{t,out}}$

bwr = (T₂ -T₁)/[(T₄ - T₅) +(T₆ -T₇)] = (649.01 - 300)/((1400 - 909.5) + (1400 - 909.5)) = 35.58%

c. Power = 6 kg *492.9525 KJ/kg = 2957.715 KW

3 0

3 years ago

28. What is the value of a resistor in a series circuit if you measure 0.5 amps flowing through it and 15 volts

Anna35 [415]

The girls name on my phone I am in my name is

7 0

3 years ago

A 10-mm steel drill rod was heat-treated and ground. The measured hardness was found to be 290 Brinell. Estimate the endurance s

grandymaker [24]

Answer:

the endurance strength $S_e$ = 421.24 MPa

Explanation:

From the given information; The objective is to estimate the endurance strength, Se, in MPa .

To do that; let's for see the expression that shows the relationship between the ultimate tensile strength and Brinell hardness number .

It is expressed as:

$200 \leq H_B \leq 450$

$S_{ut} = 3.41 H_B$

where;

$H_B$ = Brinell hardness number

$S_{ut}$ = Ultimate tensile strength

From ;

$S_{ut} = 3.41 H_B$ ; replace 290 for $H_B$ ; we have

$S_{ut} = 3.41 (290)$

$S_{ut} =$ 988.9 MPa

We can see that the derived value for the ultimate tensile strength when the Brinell harness number = 290 is less than 1400 MPa ( i.e it is 988.9 MPa)

So; we can say

$S_{ut} < 1400$

The Endurance limit can be represented by the formula:

$S_e ' = 0.5 S_{ut}$

$S_e ' = 0.5 (988.9)$

$S_e '$ = 494.45 MPa

Using Table 6.2 for parameter for Marin Surface modification factor. The value for a and b are derived; which are :

a = 1.58

b = -0.085

The value of the surface factor can be calculate by using the equation

$k_a = aS^b_{ut}$

$K_a = 1.58 (988.9)^{-0.085$

$K_a = 0.8792$

The formula that is used to determine the value of $k_b$ for the rotating shaft of size factor d = 10 mm is as follows:

$k_b = 1.24d^{-0.107}$

$k_b = 1.24(10)^{-0.107}$

$k_b = 0.969$

Finally; the the endurance strength, Se, in MPa if the rod is used in rotating bending is determined by using the expression;

$S_e =k_ak_b S' _e$

$S_e$ = 0.8792×0.969×494.45

$S_e$ = 421.24 MPa

Thus; the endurance strength $S_e$ = 421.24 MPa

8 0

3 years ago

a vertical cylindrical container is being cooled in ambient air at 25 °C with no air circulation. if the initial temperature of

Sloan [31]

Answer:

the surface heat-transfer coefficient due to natural convection during the initial cooling period. = 4.93 w/m²k

Explanation:

check attachement for answer explanation

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Whats the difference between GeForce GTX 1060 and Geforce GTX 3060? Is there any big changes to FPS and other settings?

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Answer:

uhhhhh, are you kidding? a GTX 3060 is far better than a 1060 ding dong

Explanation:

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