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).
Experiment measuring the coefficient of heat transmission through copper rods under varying pressures, including a formula and a graph of results.
| Identifier | ExFiles\Box 58\2\ Scan131 | |
| Date | 14th June 1934 guessed | |
| F.I.M.A.C. MILANO -4- a small copper rod resting on another small copper rod dipped in the mercury. The calorimeter was then mounted on a swinging bracket and arranged in such a way that the two copper rods tested on one another with pressures which could vary, as shown in the attached figure Nº2; readings were taken of the time of heating from 30 to 35º, with loads such as to produce pressures between the two surfaces, of 0,1,2,3,4,6 Kg. per s.m.m. The values of the coefficient of transmission of heat for the rod being examined, were determined on the basis of the times found, and the said rod was of the following measurements: Diameter - 4.5 mm. Length - a 2.5 mm. by means of the formula: A = (Q / (tl - t)) . (3600 / 7) in which tl - t is the jump of temperature between the mercury and the calorimeter, T the time taken to heat the calorimeter from 30 to 35º and Q is the usual 0,389. The results of the following diagram were obtained: [Graph Data] - Y-axis (Coefficient of transmission): 0,1823, 0,1600, 0,1400, 0,1200, 0,0993 - X-axis (Pressure in Kg. per s.m.m.): 0 1 2 3 4 5 6 The maximum value of A found with pressure of 6 Kg. per s.m.m. is 0,1823, which is very near to that which could be obtained by applying to a continuous rod, the value of A given by treatises of physics. | ||