Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 3, pp. 527−532.
Pleiades Publishing, Ltd., 2012.
Original Russian Text
I.M. Piskun, G.N. Abaev, 2011, published in Khimicheskaya Promyshlennost’, 2011, Vol. 88, No. 7, pp. 412−417.
MODELING AND CALCULATION
OF TECHNOLOGICAL PROCESSES
Designing of the Jet Device as the Element of the Heat Pump
I. M. Piskun and G. N. Abaev
“Naftan” OJSC, Polotsk, Russia
Received September 9, 2011
Abstract—The problems are examined of the effective functioning of the jet device as the main element of the
heat pump allowing the recuperation of the low potential thermal energy. Regularities of the ejection, which are the
basis for designing of the ejector and ejection apparatus, are described. It is shown that the effective ejection can be
reached at developed regime of outﬂ ow of the liquid from the nozzle (Re>10
). The common expression describing
the coefﬁ cient of ejection for cases with cylindrical and ﬂ at nozzle on jet devices of various scales is presented. It
is determined that ﬂ at nozzles can develop bigger values of Ke at the other equal conditions. The requirement for
designing main elements of the ejector, which have to be followed for achievment of high values of coefﬁ cients
of ejection, are formulated.
We have developed  a steam-air compression heat
pump for recuperation of low potential thermal energy,
which can be applied, in particular, in heating system of
dwelling houses, or in industrial enterprises in systems
of water circulation for cooling of the industrial equip-
ment. One of the main elements of the heat pump is the
jet device, which uses ejector for formation of the work-
ing body in closed loop of the heat pump. Therefore, the
most important condition for achievement of the effec-
tive functioning of the heat pump (E > 3) is the effective
ejection in the jet device.
EJECTION. INFORMATION AND REGULARITIES
The ejection consists in the transfer of the kinetic
energy by one ﬂ ow to another by direct contact (mix-
ing), i.e. one stream with high energy entrains another
stream. The ﬂ ow, coming to the process of mixing with
higher velocity, is called working, and that with lower
velocity, ejected ﬂ ow. Schematic diagram of the ejector
is illustrated on Fig. 1.
Main elements of the ejector are as follows: The
stream of the working medium goes from the nozzle 1 at
high velocity into the suction chamber 2 and entrains the
ejected medium due to the surface friction. Therewith,
Fig. 1. Schematic diagram of the ejector. (1) the working nozzle, (2) the suction chamber, (3) the confuser, (4) the mixing chamber, (5)
Ejecting ﬂ ow
Entrained ﬂ ow