Superheat Degree
Compute the superheat of a refrigeration system, ΔT = T_suction − T_evaporation(saturation), how much hotter the refrigerant vapor is than its saturation temperature at the evaporator pressure. Proper superheat (typically 5–10 °C) ensures only vapor (no liquid) reaches the compressor, protecting it from liquid slugging. Too much superheat reduces capacity. It is controlled by the expansion valve. Enter the suction and saturated evaporation temperatures.
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Superheat degree
At the evaporator outlet the refrigerant has already boiled off all of its liquid and keeps absorbing heat — ending up a few degrees hotter than its saturation temperature. That difference is the superheat: ΔT = T_suction − T_evaporating(saturation). Why does it matter so much? Because it guarantees that only vapor, and never liquid, reaches the compressor. Liquid is incompressible — if droplets reach the cylinder, the dreaded liquid slugging occurs, which can break valves and connecting rods instantly. Healthy superheat (typically 5–10 °C) is the safety margin. But there is a balance to strike: superheat that is too low risks slugging; too high means part of the evaporator is being used merely to heat vapor (instead of boiling liquid and removing useful heat), cutting cooling capacity and driving up the discharge temperature. That is exactly what the thermostatic expansion valve (or its electronic counterpart) controls: it modulates the liquid flow into the evaporator to hold superheat on target. Measuring superheat is the number one check any refrigeration technician makes. Enter the suction temperature and the saturated evaporating temperature.
Related Tools
Subcooling Degree
Compute the subcooling of a refrigeration system, ΔT = T_condensation(saturation) − T_liquid, how much colder the liquid refrigerant is than its saturation temperature at the condenser pressure. Proper subcooling (typically 4–8 °C) ensures pure liquid (no vapor bubbles) at the expansion-valve inlet, avoiding flash gas that reduces capacity. It increases the refrigerating effect. Enter the saturated condensation temperature and the liquid temperature.
Compressor Volumetric Displacement
Compute the volumetric displacement of a reciprocating compressor, Vd = (π/4)·D²·L·n, the volume swept by the pistons, from the cylinder bore (D), the stroke (L) and the number of cylinders (n). It is the compressor's 'displacement' — the theoretical volume aspirated per revolution, which, multiplied by the speed and the volumetric efficiency, gives the actual flow. It defines the compressor capacity. Enter the bore, the stroke and the number of cylinders.
Compressor Work (Isentropic)
Compute the specific compression work in an ideal refrigeration cycle, W = h₂ − h₁, the enthalpy difference between the compressor outlet and inlet (isentropic compression, at constant entropy). It is the energy the compressor adds to the refrigerant per kilogram — the cycle's 'electricity bill'. Together with the refrigerating effect, it defines the COP (COP = refrigerating effect/work). Enter the outlet and inlet enthalpies.
Compressor Volumetric Efficiency
Compute a compressor's volumetric efficiency, ηv = (actual suction flow / volumetric displacement)·100%, the fraction of the piston-swept volume that actually pumps gas. Losses come from clearance volume (gas that re-expands), suction reheating and leakage. It drops as the compression ratio rises. It is a key indicator of compressor performance. Enter the actual suction flow and the volumetric displacement.
Distribution Coefficient (Extraction)
Compute the distribution (or partition) coefficient of a liquid-liquid extraction, KD = concentration in the extract / concentration in the raffinate, the ratio of how the solute distributes between the two immiscible phases at equilibrium. A high KD means the solvent extracts the solute well, requiring fewer stages and less solvent. It is the central parameter of extractor design and solvent choice. Enter the extract and raffinate concentrations.
Valve Rangeability
Compute the rangeability (turndown) of a control valve, R = Qmax/Qmin, the ratio of the largest to the smallest flow it controls accurately. A high rangeability (e.g. 50:1) means the valve works well at both high and low flows, offering fine control over a wide range. It is a key criterion in valve selection. Enter the maximum and minimum controllable flows.
The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.