Wyniki wyszukiwania - BazTech

1

Stirling engines - the state of technology development and computational models

Furmanek Mariusz, Kropiwnicki Jacek

Combustion Engines

|

2022

|

R. 61, nr 1

3--12

EN

Stirling engines represent a technologically important solution in combined heat and power systems. Their use enables the achievement of over 90 percent efficiency in the management of the primary energy source with a very high durability of the device, mainly due to the lack of contact of the working gas with external factors and a very small number of mechanical components. The use of a Stirling engine may be equally important when applying renewable energy sources or waste heat from other processes. The first part of the work presents an overview of available commercial Stirling engine solutions. The second part of the work presents an overview of numerical models of Stirling engine operation, which enable the correct selection of the main geometrical features of the devices and the improvement of the structure in order to maximize efficiency or power.

2

Analysis of the regenerative braking process for the urban traffic conditions

Kropiwnicki Jacek, Furmanek Mariusz

Combustion Engines

|

2019

|

R. 58, nr 3

203--207

EN

In a regular drive system, with an internal combustion engine, vehicle braking is connected with the unproductive dissipation of kinetic and potential energy accumulated in the mass of the vehicle into the environment. This energy can constitute up to 70% of the energy used to drive a vehicle under urban conditions. Its recovery and reuse is one of the basic advantages of hybrid and electric vehicles. Modern traffic management systems as well as navigation systems should take into account the possibility of the energy recovery in the process of regenerative braking. For this purpose, a model of a regenerative braking process may be helpful, which on the one hand will enable to provide information on how traffic conditions will affect the amount of energy dissipated (wasted) into the atmosphere, on the other hand will help to optimize the route of vehicles with regenerative braking systems. This work contains an analysis of the process of the regenerative braking for the urban traffic conditions registered in Gdańsk. A model was also presented that allows calculating the amount of energy available from the braking process depending on the proposed variables characterizing the vehicle traffic conditions.

3

Hydraulic resistance analyses of selected elements of the prototype Stirling engine

Furmanek Mariusz, Kropiwnicki Jacek

Archives of Thermodynamics

|

2019

|

Vol. 40, no 3

123--136

EN

The paper presents the results of simulation tests of hydraulic resistance and temperature distribution of the prototype Stirling alpha engine supplied with waste heat. The following elements were analyzed: heater, regenerator and cooler. The engine uses compressed air as a working gas. Analyses were carried out for three working pressure values and different engine speeds. The work was carried out in order to optimize the configuration of the engine due to the minimization of hydraulic resistance, while maintaining the required thermal capacity of the device. Preliminary tests carried out on the real object allowed to determine boundary and initial conditions for simulation purposes. The simulation assumes that there is no heat exchange between the regenerator and the environment. The solid model used in simulation tests includes the following elements: supply channel, heater, regenerator, cooler, discharge channel. Due to the symmetrical structure of the analyzed elements, simulation tests were carried out using 1/6 of the volume of the system.