Quick Answer
Calculate Screw Compressor Oil Injection Rate & Cooling Duty Calculator (COP-Referenced Energy Balance)
Calculator
Result Interpretation
Screw Compressor Oil Injection Rate & Cooling Duty Calculator (COP-Referenced Energy Balance) Calculator computes Oil injection mass flow rate in kg/s using the defined engineering formula and the input values provided.
Worked Example
Verified calculation
Given:
- Coefficient of Performance = 3
- Discharge enthalpy (refrigerant) = 432.5
- Suction enthalpy (refrigerant) = 401.1
- Refrigerant mass flow rate = 0.4
- Oil inlet specific enthalpy = 118.2
- Oil outlet specific enthalpy = 162.7
Expected Result:
- Oil injection mass flow rate = 0.094082397003745
Engineering Interpretation:
Under the given input conditions, the calculated result is: Oil injection mass flow rate = 0.094082397003745 kg/s.
The actual numerical result is computed by the Runtime engine using the persisted tool definition. The values shown here come from automatically validated test cases.
Formula / Method
oil injection mass flow rate = (refrigerant mass flow rate * (refrigerant - refrigerant)) / (coefficient of performance * (oil outlet specific enthalpy - oil inlet specific enthalpy))Formula family: formula_refrigeration_screw_compressor_oil_injection_rate_cooling_duty_calculator
Variables
| Symbol | Label | Role | Description |
|---|---|---|---|
| m_dot_r | Refrigerant mass flow rate | INPUT | Refrigerant mass flow rate |
| h_dis | Discharge enthalpy (refrigerant) | INPUT | Discharge enthalpy (refrigerant) |
| h_suc | Suction enthalpy (refrigerant) | INPUT | Suction enthalpy (refrigerant) |
| COP | Coefficient of Performance | INPUT | Coefficient of Performance |
| h_oil_in | Oil inlet specific enthalpy | INPUT | Oil inlet specific enthalpy |
| h_oil_out | Oil outlet specific enthalpy | INPUT | Oil outlet specific enthalpy |
| mass_flow_rate | Oil injection mass flow rate | OUTPUT | Oil injection mass flow rate |
Calculation Steps
- Enter the refrigerant mass flow rate in kg/s.
- Enter the discharge enthalpy (refrigerant) in kJ/kg.
- Enter the suction enthalpy (refrigerant) in kJ/kg.
- Enter the coefficient of performance in dimensionless.
- Enter the oil inlet specific enthalpy in kJ/kg.
- Enter the oil outlet specific enthalpy in kJ/kg.
- Step 1: Compute oil injection mass flow rate.
- Read the oil injection mass flow rate (kg/s) from the results.
Engineering Summary
Calculate Screw Compressor Oil Injection Rate & Cooling Duty Calculator (COP-Referenced Energy Balance)
Frequently Asked Questions
What does this calculator calculate?
The Screw Compressor Oil Injection Rate & Cooling Duty Calculator (COP-Referenced Energy Balance) Calculator estimates Oil injection mass flow rate based on the input parameters you provide
Why is refrigerant mass flow rate important in this calculation?
refrigerant mass flow rate is directly proportional to oil injection mass flow rate. When you enter refrigerant mass flow rate in kg/s, the calculator uses it in the engineering formula to compute the output
How should I interpret the result oil injection mass flow rate?
The calculator outputs oil injection mass flow rate in kg/s. To convert to kg/h, multiply the result by 3600. To convert to g/s, multiply by 1000. The result is computed directly from the input values using the defined engineering formula
What units should I use for the inputs?
Enter each value in the units shown next to the input field: Refrigerant mass flow rate (kg/s), Discharge enthalpy (refrigerant) (kJ/kg), Suction enthalpy (refrigerant) (kJ/kg), Coefficient of Performance (dimensionless), Oil inlet specific enthalpy (kJ/kg), Oil outlet specific enthalpy (kJ/kg). Make sure all inputs use the specified units for consistent results
What assumptions does this calculator use?
This calculator uses automatically validated engineering formulas. Results are approximate and should be validated against site-specific conditions, applicable codes, and professional engineering judgment
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