**Abbreviations**

LH specific latent heat (kJ/kg) *m*\_ mass flow rate (kg/s) *p* pressure (kPa)

*R* gas constant (kJ/kg K) *T* temperature (°C) *v* specific volume (m<sup>3</sup>

*V* air velocity (m/s) *V*\_ volume flow rate (m<sup>3</sup>

*Low-temperature Technologies*

**Greek letters**

**Subscripts**

*a* air

*x* dryness fraction (�) *w* specific work (kJ/kg)

*β* mass ratio *m*\_ *<sup>a</sup>=m*\_ st*,*<sup>t</sup> (�) *γ* mass ratio *m*\_ *st,ce=m*\_ st*,*<sup>t</sup> (�) *δ* mass ratio *m*\_ *st, vp=m*\_ st*,*<sup>t</sup> (�)

Δ*T*rc,sub subcooling in the refrigerant condenser

*ε* heat exchanger effectiveness (�) *ζ* mass ratio *m*\_ cw*=m*\_ st*,*<sup>t</sup> (�)

respectively (�)

ace air cooler exit for chilled water aci air cooler inlet for chilled water

*m* air and steam mixture, mechanical

c steam condenser, cooling ce steam condenser outlet ci steam condenser inlet

*φ* relative humidity (�)

ac with air cooler

atm atmospheric av. average

cw chilled water *e* evaporator ha humid air i isentropic in inlet

*r* refrigerant

st steam

**240**

rc refrigerant condenser rco refrigerant compressor *s* saturated steam

ing the vacuum pump (K/°C)

*η<sup>i</sup>* isentropic efficiency of the compressor (�) *η<sup>m</sup>* mechanical efficiency of the compressor (�)

*q* relative heat transfer rate (kW/kg)

/kg)

/s)

Δ*T*ce temperature difference of steam at condenser inlet and exit (K/°C) Δ*T*<sup>e</sup> temperature difference of chilled water at air cooler inlet and saturated refrigerant in VCRS evaporator (K/°C)

Δ*T*vpi temperature difference of condensate in hot well and air enter-

*ξI, ξII, ξ<sup>t</sup>* mass ratios *m*\_ <sup>r</sup>*,*I*=m*\_ st*,*<sup>t</sup> , *m*\_ <sup>r</sup>*,*II*=m*\_ st*,*<sup>t</sup> , and *m*\_ <sup>r</sup>*,*<sup>I</sup> þ *m*\_ ð Þ <sup>r</sup>*,*II *=m*\_ st*,*<sup>t</sup> ,

