We have learned Vapor Absorption Machine chiller operations in detail, and in that, we have learn what COP is and the formula. To calculate easily, we have created the VAM Chiller COP Calculator, where you can just enter the values and it gives you the result.
LiBr-Water VAM Chiller COP Calculator
Simple calculator for Vapor Absorption Machine chillers
Calculation Results
Cooling Capacity
Steam Input
Performance
Features of the calculator
Get the COP of the chilled just by entering the data below.
- Inlet Temperature
- Outlet Temperature
- Steam Flow Rate
- Steam Pressure
- Cooling Capacity
What is the COP of the VAM chiller? How to calculate?
COP is a dimensionless ratio that measures the efficiency of a cooling or heating system. It represents the amount of cooling (or heating) output you get per unit of energy input.
It can be calculated using the formula below
Higher COP = Better Efficiency
Lower COP = Lower Efficiency
We have posted various chemical engineering calculators, such as the Cooling Tower Calculator, which lets you easily calculate cooling tower efficiency.
Example
A VAM chiller operates with a chilled water flow rate of 25 m³/hr and a temperature drop (ΔT) of 5°C across the evaporator. The generator requires 170 kW of heat input, and the pump consumes 2 kW. Calculate the COP of the VAM chiller.
Given, Chilled water flow rate: 25 m³/hr
Chilled water ΔT: 5°C
Heat input to generator: 170 kW
Pump power: 2 kW
First, calculate the cooling effect from ΔT.
Step 1: Convert flow rate to kg/s
Water density ≈ 1000 kg/m³
25 m³/hr = 25,000 kg/hr
= 25,000 / 3600
≈ 6.94 kg/s
Step 2: Calculate cooling effect
Formula:
Q = m × Cp × ΔT
Where Cp ≈ 4.186 kJ/kg·°C
Q = 6.94 × 4.186 × 5
Q ≈ 145.3 kW (Cooling Output)
Step 3: Calculate COP
COP = Cooling Output / (Heat Input + Pump Power)
COP = 145.3 / (170 + 2)
COP = 145.3 / 172
≈ 0.844
Final COP: ≈ 0.84
1. What input values do I need to use in this calculator?
You only need the chilled water flow rate, the chilled water ΔT, the heat input to the generator, and any pump or auxiliary power. The calculator uses these to compute the cooling effect and then the COP.
2. What is a “good” COP value for a VAM chiller?
Single-effect VAM chillers normally show a COP of 0.6–0.8. Double-effect units are higher, usually 1.0–1.3, and triple-effect systems can reach 1.4–1.7 in good operating conditions. Lower COP, might be due to poor vacuum, fouling, low chilled-water ΔT, or incorrect flow rates.
3. How is the cooling output (chilled water effect) calculated from flow rate and ΔT?
You convert the chilled water flow to mass flow (kg/s) using water’s density. Then apply Q=m˙⋅Cp⋅ΔT to get the cooling effect in kW. Then use that in the COP formula.