Measuring the power developed by the installation of WHD-2 was carried out on the shaft of a gear with the dynamometer. Dynamometer scheme is shown in Fig. 19.
On the platform 1 of a pilot plant with WHD-2 shaft 2 is mounted rotatable and base 3 dynamometer. On the shaft 2 is located in gear 4, which rotates with the shaft (the direction of rotation indicated by arrow 5). The base 3 by means of rolling node 6 is connected with a rack 7, at the end of which, at a distance L1 from the node bearing 6 mounted dynamometer 8. Also on the stand of 7 at a distance L2 from the site of 6 is rolling metal support 9, which is based on the free end of the pinion 1 at a distance «L3» from the axis of the shaft 2. 4 is located on the gear indicator 10. Based on 3 well established base 11 with sensor 12 for measuring the speed «n» of rotation of gear 4 with indicator 10. The results of measurement of revolutions «n» on the wire 13 are transmitted to the display 14 (the 10, the sensor turns 12, the wire 13 and display 14 is a bike computer model of the series AS ASSIZE, made in China).
The measurements on the dynamometer useful work, withdrawn in the form of power in the interaction of oscillating working elements of the unit WHD-2 with a flow of fluid to occur as follows. The mechanical energy of oscillating working elements of the unit WHD-2 is converted into rotational energy of the shaft 2 and the gear 4. By applying to a dynamometer 8 effort "Pd" in the direction perpendicular to the plane of the gear 4, there is an effort «R» gear 4 to the point of contact the support 9 with the pinion 4, an equal and opposite true normal pressure at the point of application of force, "Pu", kg. Change speed gear 4 is determined by the indicator 10 and speed sensor turns 12 and is fixed on the display 14.
The main measurement error on this dynamometer is the error of the operator. When working on a chassis dynamometer of the same operator measurement error for the qualitative test can be neglected.
The formula for determining the actual capacity of Ne on the shaft of the pinion of the force F is given in :
Ne = Mt * n / 97 400 [kg * cm * / min = KW] (13)
Mt - torque on the shaft gears;
n - rotational speed, gear, bike computer measured a series of AS model ASSIZE (China), rev / min;
97 400 - a dimensionless coefficient;
Mt = Pf * L3, kg * cm (14)
Pf - friction that arose at the point of application of force F;
L3 = 13,0 cm - shoulder to the point of application of force P to the axis of rotation of the shaft gears;
Pf = f * Pn kg (15)
f = 0,2 - coefficient of friction obtained experimentally;
Pn - a true normal pressure at the point of application of force P, kg.,
calculated by the formula:
Pn = Pp * L1 / L2 (16)
L1 = 530 mm .- shoulder of the dynamometer to the axis of the chassis dynamometer;
L2 = 300 mm. - Leverage from the point of application of force P to the axis of the chassis dynamometer;
Pp - normal force pressure at the point of application of force F on the surface of the gear, measured on the scale of the dynamometer is given by:
Pp = Pd + Pst, kg., (17)
Pd - readings measuring dynamometer, kg.;
Pst = 0.4 kg. - the static weight of the movable part of the chassis dynamometer
with a dynamometer;
Rn = Pp * 530/300
Rn = Pp * 1.7, kg. (18)