The centrifugal pump type has a number of its advantages inside of the low - sized pumps group. The main ones from them are the following:
- The Work Resourсe.
The "Molniya" space vehicles (SV) have been become the first generation of the Soviet communications satellites. The temperature control system (TCS) in these SV has been carried out by the pump - circulation scheme. So, the preference has been given to the rotary gear pump at the pump type choice for the "Molniya" first model TCS (e.g. at the end of the 50 - es), by that time, it has been shown itself to a good advantage in the missiles steering engines composition. Thus, the TCS work resource of the first "Molniya" SV with the rotary gear pumps has been appeared to be inadmissibly low, in the process of its operations and the maintenance. Therefore, they have begun to employ the centrifugal pumps, having permitted to be increased the work resource up to several decades thousand hours in the all subsequent "Molniyakh".
- The Work Economy in the Regime Parameters Wide Range.
The low - sized centrifugal pumps with the φ≤0.1 discharge coefficient are being functioned with the efficiency acceptable level in the ns=40...200 specific speed values range. This range is considerably narrower for the low - sized pumps another types. It is made up ns=10...30 at the vortex pumps, and it is made up ns=30...40 at the disk ones. The centrifugal pumps reasonable application field has been become dominating with the following number of revolutions increase up to n=10,000 rpm, for example, on the field of the temperature control (TC) LCHS needed regimes.
At the present day, the centrifugal low - sized pumps are the supercharger main type of the low - consumed hydraulic systems in the aviation and the space technology and the engineering, owing to better combination of the energy, the mass overall dimensions and the resource characteristics.
Let us consider the requirements to the centrifugal pump rotor wheel flowing form, having designed for the functioning in the temperature control LCHS with the following parameters: Δрhs hydraulic resistance of the LCHS circulation tract is being changed in the range of Δрhs =(0.03...0.2) Mpa, and the working substance consumption is not exceeded 300×10-6 m3/s. Thus, we shall find out the ns specific speed, having regulated the D1/D2 ration of the scapular pumps rotor wheel, having accepted all these indicators, as the pump´s output parameters and, moreover, having taken into consideration, that the electric drives are being employed with the ω=(314...1047)×с-1 angular frequency of the shaft revolution in the LCHS.
The ns values bounds are being kept within the ns= 40...80 values range, having satisfied all the really possible combinations of the working substance combustion and the LCHS circulation tract hydraulic resistance. The ns ≤ 80 interval is meant, that the centrifugal pumps, having related to the low - speed class, are needed for the LCHS with the working substance active circulation.
The work was submitted to international scientific conference «Prospects for the development of university science», Dagomys (Sochi), September 21-24, 2009. Came to the editorial office on 03.08.2009.