From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Tests concerning the non-opening of 25/30 HP radiator shutters at high speeds.
| Identifier | ExFiles\Box 105\1\ scan0253 | |
| Date | 30th March 1936 | |
| X540 To E.{Mr Elliott - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} c. to By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to Mx.{John H Maddocks - Chief Proving Officer} 25/30 HP. Radiator Shutters - Report on tests in connection with non-opening of shutters at high road speeds. As mentioned in a previous report, G.W.H. has experienced the above-mentioned trouble on 21-G-IV and to a very bad extent on 22-G-V.{VIENNA} On other large bore cars tried by us, 18-G-IV and GUB-5, the trouble was apparent but not serious. We have therefore endeavoured to determine what can be done to reduce the trouble, without waiting for the unbalanced shutter scheme which is at present being built up. The tests were carried out on GAF-20, a small bore 20/25 car, being the only one available at the moment. The tests carried out where as follows (all tests carried out on a portion of the Six Hills Road) :- (1) Car was run until the water temperature attained was a few degrees below the opening temperature of the shutters with the car stationary. Car was then driven up to full speed and kept at full throttle until the shutters commenced to open, the maximum water temperature being noted. The top tank and cylinder block thermometer temperatures were noted. This test was repeated with and without a calorstat spring fitted. (2) Radiator was removed from the car and the overlap of the shutters was measured. Half the amount of the overlap was then removed from the leading edge of each shutter, thus rendering the shutter balance to wind pressure. The last test was then repeated. (3) To determine the effect of the unbalance caused by overlap of the side plates over the end shutters, the end shutters were removed and the first test repeated. The results are shown in tabular form attached. | ||