The usage of gradient heat flux measurement for monitoring of heat flux on combustion chamber surface and optimization of diesel work process is proposed. Heterogeneous gradient heat flux sensors can be used at various regimes for an appreciable length of time. Fuel injection timing is set by the position of the maximum point on the angular heat flux diagram however, the value itself of the heat flux may not be considered. The development of such an approach can be productive for remote monitoring of work processes in the cylinders of high-power marine engines.

Heat transfer research is one of key topics for internal combustion engine development. However, heat transfer study is a challenging task due to high value and rapid change in temperature and heat flux inside the combustion chamber. In this paper, experimental study is presented with implementation of heterogeneous gradient heat flux sensors. Heat flux was measured by a probe and at several points of a firedeck. Heat fraction to a firedeck was calculated at various engine speeds. The heat transfer coefficient at investigated points is calculated. Comparison with other studies is provided.

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The use of materials with shape memory in the manufacture of parts of the drill string such as the nipple and the coupling of the boring lock and the bit of the drill bit can improve performance, as many of the drawbacks exhibited during operation are associated with design features, and the use of alloys with shape memory allows changing the design parts, taking into account the features of the equipment due to their functional characteristics.

We used gradient thermometry to determine local heat transfer coefficients on the fire deck surface. We studied two modes of engine operation, that is, motored and fired. We show that the heat transfer coefficient distribution over the fire deck surface is inhomogeneous. Our investigation results may be used to validate existing models of heat transfer in a combustion chamber.