Fuel consumption report WM D1-22/4HBC-35 (test 15/06/02) Test and results Fuel consumption tests were carried out with a 4-inch, mixed-flow pumpset powered by a 4 hp diesel engine from China. The tests were conducted at the workshop of the earth-moving firm of the Gebr. Bom in Papendrecht, the Netherlands, from 09h00 to 17h30 on 15 June 2002. The original pumpset was a CF170F/4HBC-35 and was procured from Shanghai Wallong, China in August 2000. The pump was manufactured by Wuxi Pump Works and was previously known as model 100HW-8. The pump characteristics were confirmed at the International Agricultural College Larenstein in Deventer, the Netherlands, using a calibrated electric motor, pressure gauges and a flow meter. This confirmed the manufacturer’s data: maximum efficiency was about 79% at best efficiency point (BEP) for a discharge of 90 m3/h at a head of 8 m, which is very good for such a small pump. However, during initial fuel consumption tests in May/June 2001 it was concluded that: (1) at 2150 rpm, total head is 3.55m and the discharge is 80m3/hr, the fuel consumption is 558gr/hr (≈ 0.67 l/h); and (2) the most suitable speed for the water pump coupled to the diesel engine is 2150rpm. This conclusion was not in agreement with the performance anticipated by the HIPPO Foundation, the organization that had selected and bought the pumpset for testing purposes. Therefore, it was hypothesized that some kind of mechanical defect caused the high fuel consumption and low working speed. After a series of tests and a minor modification it was concluded that the problem was definitely in the engine, probably caused by inadequate quality control during assembly. Without workshop manuals it was impossible to identify the problem and it was decided to try and find an identical replacement machine. Both, the engine (WM D1-22) and mechanical expertise were kindly offered by Crouwers BV. The following 3 test runs were conducted on 15 June using some of the facilities of Mr. Gert Jan Bom, Solartec, Papendrecht: @ 2300 rpm, start 15h16, stop 15h46, total consumption 200 cc (=0.4 l/h) @1900 rpm, start 15h55, stop 16h10, total consumption 75 cc (=0.3 l/h) @ 2525 rpm, start 16h14, stop 16h29, total consumption 120 cc (=0.48 l/h) These values are the same or better than those found with PumpSelect, the pump selection application developed by the HIPPO Foundation (http://www.hipponet.nl/ressources/pumpselect.xls): @ 2300 rpm, fuel consumption of 0.42 l/h (Hm = 3.2, Q = 25 l/sec) @ 1900 rpm, fuel consumption of 0.28 l/h (Hm = 3.0, Q = 20 l/sec) @ 2525 rpm, fuel consumption of 0.52 l/h (Hm = 3.4, Q = 28 l/sec) Considering that a calibrated jamjar was used for actual fuel measurement, these results are very good. Observations

• compared with the WM D1-22 noise levels were down, and there was less of a banging sound compared to the CF170F;

• contrary to the CF170F there was no emission of black smoke and smelling exhaust fumes, pointing at considerable better combustion in the WM D1-22; and,

• the WM D1-22 was running more smoothly, while the CF170F seemed to skip a stroke every now and then.

If a minimum power margin of a fairly cautious 20% is maintained, the safe maximum operating speed is estimated at 2725 rpm for a discharge of 111 m3/h at Hm = 3.8 m. The safe minimum operating speed is estimated at 2000 rpm, below which the lack of balance in such a small 1-cilinder engine seems to make it run a bit less smoothly, which may reduce engine life. Fig. 1 Characteristics of pump at 2725 rpm (estimated safe maximum operating speed)

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Efficiencies Originally, it was hoped that pump/engine speeds as low as 1500 rpm could be achieved. This seems not to be the case and actually means a reduction in the efficiency at very low

lifts of about 1 m or less. One option would be to fit a smaller engine (e.g. the 199 cc version of the same engine series), or to fit another type of engine (there is quite a bit of choice in China and elsewhere). However, versatility isn’t as bad as all that. At 2000 rpm, pump efficiencies of up to 70% can still be achieved for lifts of 0.5 m (which is indeed very little) provided there are some (but still limited) friction and form losses at the suction and pressure ends. Maximum efficiency @ 2000 rpm is achieved at Q = 62 m3/h and Hm = 3.8 m. At 2725 rpm, maximum efficiency is achieved at Q = 85 m3/h and Hm = 7.1 m. With the standard Chinese foot valve (double hinged type) of 130 mm diameter and 55 meters of layflat hose of 125 mm this allows a discharge of 21 l/sec at a static lift of 5.5 m. (such long layflats are very useful on natural slopes of 7-10°, thus avoiding the need for constructing a costly pumping station). This suggests that the pumpset is very suitable for conditions along the Niger river in Timbuktu or other Sahelian rivers for the conventional irrigation of about 5 ha of flooded rice. It could also be used for supplementary irrigation in floating rice. Overall efficiency (i.e. pump efficiency x static head / manometric head) at a static head of 3 m, a discharge of 80 m3/h (or 22 l/sec) and a speed of 2350 rpm with a discharge hose of 30 m (125 mm diameter) is 50%, which is an extremely good overall efficiency value for a mobile pumpset. The static head/discharge hose values are for typical, average pumping conditions in the Timbuktu area. Fuel consumption is 0.44 l/h. If total water consumption of a hectare of flooded rice is 15000 m3, this would require 82.5 litres of diesel, which means that average diesel consumption in the area (about 125 litres of diesel per hectare) is 51.5% higher. By optimizing engine speed at all times during the pumping season, it is likely that diesel consumption values of 70-75 l/ha can be achieved without further modification. Procurement The big question is now whether an efficient, reliable marketing channel can be developed to reach poor, Sahelian peasants living on the drought-stricken borders of excellent surface sources of irrigation water, such as rivers and lakes. One option would be to involve the Yituo Group http://www.yto.com.cn/en/english/intro.htm which is present in Ivory Coast, Cameroon. Benin, Liberia, but also in Solomon Islands, Australia, Bolivia, Argentina, Venezuela, Zambia, Kenya, Romania, and Bulgaria. A visit to Yituo Benin by the president of the HIPPO Foundation in Jan 2002 made it clear that there is a willingness to import from China via the Benin office to Sahelian countries, such as Burkina Faso and Mali. A second question is how to ensure the necessary high quality of workmanship during assembly of the pumpset, the engine in particular, to avoid problems such as those encountered in the CF170F. One may hope that this problem has already been solved by the Yituo Group. A third question is whether the Yituo Group is able/willing to supply pumpsets, such as the CF170F/4HBC-35 and at what price (the original CF170F/4HBC-35 was supplied in Shanghai at US$ 368, including a suction pipe, a 130 mm foot valve, delivery elbows (2 x 55°), some spareparts, pumpset mounted on welded frame with a steel coupling between engine and pump). Other subjects to be discussed later are: (1) the need for pump rental systems, such as Hari Goumo in Timbuktu; (2) the possibility of procuring other pumpsets via Yituo (e.g. 2-inch 2-stroke 50-14 pumpsets or 6-inch, diesel powered 6HB-35 150HW-4S pumpsets for discharges up to 80 l/sec); (3) alternatives to the CF170F/4HBC-35, such as the ZJ-4-3 http://www.chinadepot.com/shupump1.html ; (4) the establishment of Yituo or HIPPO user groups to combine orders and experiences; (5) the possibilities for benefiting of existing experiences with similar pumpsets, in China, South-East Asia or elsewhere; (6) pumpset ordering requirements, frame, hoses, coupling, spare parts, manuals etc.