Refrigerant-134a at 320 kPa and 40°C undergoes an isothermal process in a closed system until its quality is 65 percent. On a per-unit- mass basis, determine the required magnitude of work and heat transfer. Use the tables for R-134a. R-134a 320 kPa 40°C The required magnitude of work is 41.823 kJ/kg. The required magnitude of heat transfer is 102.783 kJ/kg. 4

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**Title: Analysis of an Isothermal Process for Refrigerant-134a**

**Introduction to the Problem:**

Refrigerant-134a at an initial pressure of 320 kPa and a temperature of 40°C undergoes an isothermal process within a closed system. During this process, the quality of the refrigerant reaches 65 percent. The task is to determine the magnitude of work and heat transfer required per unit mass of the refrigerant. For calculations, refer to the thermodynamic tables specific to R-134a.

**System Description:**

- **Refrigerant**: R-134a
- **Initial Conditions**: 
  - Pressure: 320 kPa
  - Temperature: 40°C

**Process Details:**

The process is isothermal, which means that the temperature remains constant throughout the process at 40°C.

**Results:**

- **Work Required**: 41.823 kJ/kg
- **Heat Transfer Required**: 102.783 kJ/kg

**Diagram Explanation:**

The diagram displays a closed system with R-134a. It visually shows the initial conditions of pressure and temperature. The system remains at 320 kPa and 40°C throughout the process. The quality of the refrigerant changes as indicated in the problem, affecting the energy calculations.

**Conclusion:**

In this example, the tools of thermodynamics are used to calculate the work and heat transfer necessary for the isothermal transition of refrigerant-134a within specified constraints. Such analysis is crucial for understanding energy requirements in HVAC systems and other industrial applications involving refrigerants.
Transcribed Image Text:**Title: Analysis of an Isothermal Process for Refrigerant-134a** **Introduction to the Problem:** Refrigerant-134a at an initial pressure of 320 kPa and a temperature of 40°C undergoes an isothermal process within a closed system. During this process, the quality of the refrigerant reaches 65 percent. The task is to determine the magnitude of work and heat transfer required per unit mass of the refrigerant. For calculations, refer to the thermodynamic tables specific to R-134a. **System Description:** - **Refrigerant**: R-134a - **Initial Conditions**: - Pressure: 320 kPa - Temperature: 40°C **Process Details:** The process is isothermal, which means that the temperature remains constant throughout the process at 40°C. **Results:** - **Work Required**: 41.823 kJ/kg - **Heat Transfer Required**: 102.783 kJ/kg **Diagram Explanation:** The diagram displays a closed system with R-134a. It visually shows the initial conditions of pressure and temperature. The system remains at 320 kPa and 40°C throughout the process. The quality of the refrigerant changes as indicated in the problem, affecting the energy calculations. **Conclusion:** In this example, the tools of thermodynamics are used to calculate the work and heat transfer necessary for the isothermal transition of refrigerant-134a within specified constraints. Such analysis is crucial for understanding energy requirements in HVAC systems and other industrial applications involving refrigerants.
Expert Solution
Step 1

To find : 

The required magnitude of work 

Given : 

The pressure is  P1=320 kPa,

The Temperature is T1=40°C,

For isothermal process 

The Temperature is T2=40°C,

The quality is x2=0.65

The properties are taken From the table 134a  at pressure P1=320 kPa and T1=40°C are,

ν1=0.0753 m3kg, h1=261.6 kJkg

The properties are taken From the table 134a at T2=T1=40°C are,

Uf2=107.3 kJkg , Ufg2=143.6kJkgνf2=0.000872 m3kg , vg2=0.01995 m3kg

Formula used :

The  work done can be obtained as,

W=P1ν1lnv2v1

where P1, v is pressure and volume.

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