Answer:
yield strength before cold work = 370 MPa
yield strength after cold work = 437.87 MPa
ultimate strength before cold work = 440 MPa
ultimate strength after cold work = 550 MPa
Explanation:
given data
AISI 1018 steel
cold work factor W = 20% = 0.20
to find out
yield strength and ultimate strength before and after the cold-work operation
solution
we know the properties of AISI 1018 steel is
yield strength σy = 370 MPa
ultimate tensile strength σu = 440 MPa
strength coefficient K = 600 MPa
strain hardness n = 0.21
so true strain is here ∈ = 
= 0.223
so
yield strength after cold is
yield strength = 
yield strength = 
yield strength after cold work = 437.87 MPa
and
ultimate strength after cold work is
ultimate strength = 
ultimate strength = 
ultimate strength after cold work = 550 MPa
Answer:
a)temperature=69.1C
b)3054Kw
Explanation:
Hello!
To solve this problem follow the steps below, the complete procedure is in the attached image
1. draw a complete outline of the problem
2. to find the temperature at the turbine exit use termodinamic tables to find the saturation temperature at 30kPa
note=Through laboratory tests, thermodynamic tables were developed, these allow to know all the thermodynamic properties of a substance (entropy, enthalpy, pressure, specific volume, internal energy etc ..)
through prior knowledge of two other properties such as pressure and temperature.
3. Using thermodynamic tables find the enthalpy and entropy at the turbine inlet, then find the ideal enthalpy using the entropy of state 1 and the outlet pressure = 30kPa
4. The efficiency of the turbine is defined as the ratio between the real power and the ideal power, with this we find the real enthalpy.
Note: Remember that for a turbine with a single input and output, the power is calculated as the product of the mass flow and the difference in enthalpies.
5. Find the real power of the turbine
Answer:
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