A novel solar-powered active low temperature differential Stirling pump

Abstract

a b s t r a c tThis paper presents a novel solar-powered active Stirling converter with liquid power piston and solid controllable displacer. First, the working principle of the proposed converter is described. Then, finite time thermodynamic approach incorporating heat transfer equations are employed to determine gas temperatures in hot and cold spaces based on the assumption of imperfect regeneration. Accordingly, pressure variation of the gas due to reciprocating motion of the displacer piston is investigated using the obtained gas temperatures and Schmidt theory. Next, total work done by the converter and thermal efficiency are evaluated. Kinematic and dynamic equations governing the pump system are presented and the water flow characteristics in suction and discharge states are investigated. A simulation study is carried out through coupling and simultaneously solving the obtained equations. An optimization scheme is thus conducted to find an optimum frequency of the active converter so that a maximum power is generated. The influences of regenerator efficiency, dead volumes, and water head on the optimum operating frequency and the generated power are investigated. Finally, the proposed converter is constructed and primarily tested. The experimental outcomes clearly reveal the feasibility of pumping water at low temperature difference through the proposed active Stirling pump.

A review of sustainable solar irrigation systems for Sub-Saharan Africa

“…The need for work input necessitates the use of a separate power source. Jokar and Tavakolpour-Saleh [72] introduced a novel active low temperature differential pump that is powered predominantly by solar thermal energy and operates on the basis of the Stirling cycle. The proposed system works with a liquid piston to provide effective sealing while reducing friction generally associated with solid power pistons and the cylinder encasing the piston.…”

“…A hybrid system may be proposed that combines the Stirling pump with and external mechanical system assist for the displacer in the case of inadequate solar irradiation like that proposed by Jokar and Tavakolpour-Saleh [72]; however, their use of solar panel and battery system defeats the investment cost aspect. Other external assistance solutions such as wind power may be investigated based on local resources availability.…”

From Beale Number to Pole Placement Design of a Free Piston Stirling Engine

“…So far, various empirical and analytical theories have been devised by researchers to predict the performance of the Stirling engines [1]. The first theoretical approach towards the estimation of the engine power, known as Schmidt's theory [1,[3][4][5], was introduced for the kinematic type of the Stirling engines. Tavakolpour-Saleh et al [6] have investigated the performance of a kinematic low-temperature Stirling engine with two cylinders connected to one crankshaft.…”

“…The experimental results of the FPSE clearly demonstrated that a maximum output power of 0.68 W was found at 6.4 Hz engine speed using a 10W heat source. Kwankaomeng et al [17] presented a revolutionary approach to predict the performance of a FPSE with a swept volume of 23 cm 3 . The developed prototype engine was equipped with an air cooling system and an alcohol burner was used to heat the engine.…”

“…However, this research was just a preliminary work to determine the performance of the engine. Vichaidit et al [18] designed, manufactured, and tested a free piston Stirling engine with a swept volume of about 46.65 cm 3 . The presented prototype was able to operate within a temperature range of 100…”