ASME 88-1CE-6, presented at the Energy-Source Technology Conference and Exhibition

Fig. 5 Velocity versus anguiar dispiacement (V8 engine) attained from the inertia value using the least squares method is consistently smaller than the reference data, and eventually leads to larger velocity estimation error than the average method Some precautions are needed when applying the least squares method to compute the engine inertia value. For engines operating at high speeds, the velocity related term in Eq. (1) could be very large compared with the other terms. This could result in some confusing situations. For instance, engines might decelerate over some portion of the engine operation cycle while the net external torque accelerating the engine is positive; or engines might accelerate while the net external torque is negative. These operation situations might make negative engine inertia value estimations possible, which is not feasible. In other cases, engines might have very small accelerations or decelerations while net external torque is moderate to large. For these cases, the calculation might lead to very large engine inertia values, which is not feasible either. The cases mentioned above are most likely to occur when engines operate at high speeds. Those erroneous data corresponding the situations above must be Altered out before applying the least squares method to the engine inertia value computation. The criterion used in this study to decide whether data should be used to calculate the engine inertia values is to check the quotient of the net external torque divided by the engine acceleration. This quotient should not be too large or too small relative to the average engine inertia value. Those data whose quotient are significantly away from the average engine inertia value are likely to fall in the situations mentioned above, and those data should not be used in the engine inertia value computation. V Conclusions The engine inertia values calculated by the least squares method guarantees minimum acceleration and velocity estimation errors for engine operating at constant average velocities. As for monotonically accelerating and decelerating engines, simulations in the study show that the engine model with an inertia calculated by the least squares method leads to smaller estimation errors in acceleration but larger estimation errors in velocity than the constant inertia engine model with an average inertia. It is important that the user knows the type of engine, its range of operation, and the type of loading in order to calculate an optimal engine inertia for the control purpose. This study has provided guidance in understanding the effects of engine performance variables and in calculating an appropriate estimate for the engine inertia. Acknowledgment

Survey of Papers on Elasticity Published in Holland 1940-1946

This article appeared in the first volume of a series on Advances in Appplied Mechanics, started in 1948. The author had been invited by the editors to contribute a survey of work done in The Netherlands during the Second World War, in the field of applied mechanics. In particular in the field of elasticity. The article describes work carried out by the Laboratory for Applied Mechanics of the Technische Hoogeschool at Delft (Faculty of Mechanical Engineering), by the Nederlandse Centrale Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek (TNO) in The Hague, and by the Nationaal Luchtvaartlaboratorium (NLL) in Amsterdam.Mechanical, Maritime and Materials Engineerin

De beteekenis der Wiskunde als Hulpwetenschap der Toegepaste Mechanica. Rede, uitgesproken bij de aanvaarding van het Ambt van Hoogleraar in de Toegepaste Mechanica aan de Technische Hoogeschool te Delft, den 30en September 1914.

Intreerede van prof.ir. C.B. Biezeno.Mechanical, Maritime and Materials Engineerin

Rede, uitgesproken op den gedenkdag van de Technische Hoogeschool op 8 januari 1938 door den Rector Magnificus, Professor dr.ir. C.B. Biezeno.

Delft University of Technolog

Rede, uitgesproken Maandag 19 September 1949, door de rector magnificus Prof.Dr.Ir. C.B. Biezeno

Delft University of Technolog