C O N T E N T S

Key words: absorption, refrigeration, heat pump, exergy, COP.
ALLOCATION OPTIMALE DES ÉCHANGEURS DE CHALEUR
DANS LES SYSTÈMES BOOTSTRAP EN BOUCLE OUVERTE
DES AERONEFS
par
BOGDAN HORBANIUC et GHEORGHE DUMITRAŞCU
Abstract. The open-loop bootstrap systems are driven by turbojet
aircraft engines to cool the cabin and save energy. The aim of the paper
is to optimize from the thermodynamic point of view the two heat
exchangers (main and regenerative) of the bootstrap system. The
optimization criterion is the minimum power extracted from the engine.
The constraint is the limited capacity of heat exchangers to transfer heat.
We developed a mathematical model of the system and we analyze the
ideal case (reversible adiabatic compression and expansion).
Key words: open loop system bootstrap, thermodynamic
optimization, optimal allocation
ANALYSE DES PERFORMANCES D’UNE POMPE À CHALEUR
À ABSORPTION
par
DRAGOŞ HERA et CĂTĂLINA VASILESCU
Abstract. The absorption heat pumps arise a growing interest
among researchers because they can use renewable or inexpensive (heat
recovery) energy sources. This paper presents a mathematical model
recently developed by the authors to calculate the state parameters and
process for the cycle of absorption heat pump with ammonia-water
mixture. The model applies the conservation equations for mass and
energy for each unit making up the installation. Using the computer
program developed the performance of absorption heat pump with
ammonia-water mixture is studied as a function of selected input
parameters: the temperature of the heating agent and the temperature of
the heat sink. It also analyzes the influence of these parameters on the
temperature of hot water prepared.
Key words: heat pump, absorption cycle, ammonia-water solution,