Question:
Act like a helpful tutor and exlain me :
Give step-by-step solution with explanation and final answer: Given: 130m? of water in a boiling water reactor is operating at 1000 kPa with a quality of 11.59%. An incident occurs where:
the flow of fluid through the reactor stops and thus the volume remains constant. Afer a certain time period, the water has
reached the saturated vapor phase.
Find:
3) The final temperature and pressure of the water.
b) Amount of work done on the water
©) Amount of heat added to the water
d) Time to reach the final state if the water is being heated at a rate of 14,717 kis
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Let's break down and solve the problem **step by step**.
---
## **Given Data**
- **Volume of water:** \( V = 130 \, \text{m}^3 \)
- **Initial Pressure:** \( P_1 = 1000 \, \text{kPa} \)
- **Initial Quality:** \( x_1 = 11.59\% = 0.1159 \)
- **Final State:** Water is saturated vapor (\( x_2 = 1 \)), and volume is constant.
- **Heating rate:** \( \dot{Q} = 14,717 \, \text{kJ/s} \)
---
## **a) Final temperature and pressure of the water**
### **Step 1: Initial State Properties**
From steam tables at \( P_1 = 1000 \) kPa:
- \( v_f @ 1000\, \text{kPa} = 0.001127 \, \text{m}^3/\text{kg} \)
- \( v_g @ 1000\, \text{kPa} = 0.1944 \, \text{m}^3/\text{kg} \)
- \( T_{sat} @ 1000\, \text{kPa} = 179.88^\circ \text{C} \)
### **Step 2: Find Initial Mass**
Specific volume at initial state:
\[
v_1 = v_f + x_1 (v_g - v_f)
\]
\[
v_1 = 0.001127 + 0.1159 \times (0.1944 - 0.001127)
\]
\[
v_1 = 0.001127 + 0.1159 \times 0.193273
\]
\[
v_1 = 0.001127 + 0.022420 = 0.023547 \, \text{m}^3/\text{kg}
\]
Total mass:
\[
m = \frac{V}{v_1} = \frac{130}{0.023547} \approx 5523.4 \, \text{kg}
\]
### **Step 3: Final State (Saturated Vapor, Volume Constant)**
At final state, \( v_2 = v_1 \) and \( x_2 = 1 \) (saturated vapor):
Set \( v_g = v_1 \) and find the corresponding pressure from steam tables.
Looking for \( v_g \approx 0.02355 \, \text{m}^3/\text{kg} \):
From steam tables:
- At \( P \approx 6300 \, \text{kPa} \), \( v_g \approx 0.02355 \, \text{m}^3/\text{kg} \)
- Corresponding temperature: \( T_{sat} @ 6300\, \text{kPa} \approx 275.6^\circ \text{C} \)
### **Final Answers for (a):**
- **Final Pressure:** \( P_2 \approx 6300 \, \text{kPa} \)
- **Final Temperature:** \( T_2 \approx 275.6^\circ \text{C} \)
---
## **b) Amount of Work Done on the Water**
For **constant volume process**, **boundary work** is zero:
\[
W = \int_{V_1}^{V_2} P \, dV = 0
\]
---
## **c) Amount of Heat Added to the Water**
\[
Q = m(u_2 - u_1)
\]
**From steam tables:**
- At \( P_1 = 1000 \, \text{kPa}, x_1 = 0.1159 \):
- \( u_f = 762.81\, \text{kJ/kg} \), \( u_g = 2013.6\, \text{kJ/kg} \)
- \( u_1 = u_f + x_1(u_g - u_f) \)
- \( u_1 = 762.81 + 0.1159 \times (2013.6 - 762.81) \)
- \( u_1 = 762.81 + 0.1159 \times 1250.79 \)
- \( u_1 = 762.81 + 145.00 = 907.81\, \text{kJ/kg} \)
- At \( P_2 = 6300 \, \text{kPa}, x_2 = 1 \):
- \( u_g @ 6300 \, \text{kPa} \approx 2594.0 \, \text{kJ/kg} \) (verify with steam tables)
\[
Q = m(u_2 - u_1) = 5523.4 \times (2594.0 - 907.81)
\]
\[
Q = 5523.4 \times 1686.19 \approx 9,\!316,\!000\, \text{kJ}
\]
---
## **d) Time to Reach Final State**
\[
Q = \dot{Q} \cdot t \implies t = \frac{Q}{\dot{Q}}
\]
\[
t = \frac{9,\!316,\!000}{14,\!717} \approx 633.3\, \text{s}
\]
\[
t \approx 10.56\, \text{min}
\]
---
## **Summary Table**
| Part | Description | Value |
|------|----------------------------------------------|-------------------------------|
| a | Final Pressure, Temperature | 6300 kPa, 275.6°C |
| b | Work Done | 0 |
| c | Heat Added | 9,316,000 kJ |
| d | Time to Reach Final State | 633.3 s (10.56 min) |
---
**Let me know if you need steam table references or further clarifications!**