Provided are a fluid circulation system and a method for operating same, a computer-readable medium, and a controller. The fluid circulation system comprises: a scroll expander, and an external fluid circulation path, which comprises a high-pressure fluid pipe and a low-pressure fluid pipe. The operation method comprises the following steps: before fluid is supplied to the scroll expander, making the fluid pressure in the high-pressure fluid pipe higher than the fluid pressure in the low-pressure fluid pipe by a pre-determined pressure difference; and after the pre-determined pressure difference is realized, starting the scroll expander and supplying fluid to the scroll expander. According to the present disclosure, the technical problem of a scroll expander being unable to be normally started and work can be avoided, and the invention is simple, practical, convenient, and easily implemented.

Provided are a fluid circulation system and a method for operating same, a computer-readable medium, and a controller. The fluid circulation system comprises: a scroll expander, and an external fluid circulation path, which comprises a high-pressure fluid pipe and a low-pressure fluid pipe. The operation method comprises the following steps: before fluid is supplied to the scroll expander, making the fluid pressure in the high-pressure fluid pipe higher than the fluid pressure in the low-pressure fluid pipe by a pre-determined pressure difference; and after the pre-determined pressure difference is realized, starting the scroll expander and supplying fluid to the scroll expander. According to the present disclosure, the technical problem of a scroll expander being unable to be normally started and work can be avoided, and the invention is simple, practical, convenient, and easily implemented.

A compound engine system including a Wankel engine having a recess defined in the peripheral wall of the rotor in each of the three rotating chambers, the recess having a volume of more than 5% of the displacement volume of the chambers. The expansion in the turbine section compensates for the relatively low expansion ratio of the rotary engine.

Provided are a fluid circulation system and a method for operating same, a computer-readable medium, and a controller. The fluid circulation system comprises: a scroll expander, and an external fluid circulation path, which comprises a high-pressure fluid pipe and a low-pressure fluid pipe. The operation method comprises the following steps: before fluid is supplied to the scroll expander, making the fluid pressure in the high-pressure fluid pipe higher than the fluid pressure in the low-pressure fluid pipe by a pre-determined pressure difference; and after the pre-determined pressure difference is realized, starting the scroll expander and supplying fluid to the scroll expander. According to the present disclosure, the technical problem of a scroll expander being unable to be normally started and work can be avoided, and the invention is simple, practical, convenient, and easily implemented.

Provided are a fluid circulation system and a method for operating same, a computer-readable medium, and a controller. The fluid circulation system comprises: a scroll expander, and an external fluid circulation path, which comprises a high-pressure fluid pipe and a low-pressure fluid pipe. The operation method comprises the following steps: before fluid is supplied to the scroll expander, making the fluid pressure in the high-pressure fluid pipe higher than the fluid pressure in the low-pressure fluid pipe by a pre-determined pressure difference; and after the pre-determined pressure difference is realized, starting the scroll expander and supplying fluid to the scroll expander. According to the present disclosure, the technical problem of a scroll expander being unable to be normally started and work can be avoided, and the invention is simple, practical, convenient, and easily implemented.

A scroll expander, comprising: a housing; and an expansion mechanism provided in the housing. A back pressure chamber in fluid communication with a medium pressure chamber is provided in the expansion mechanism and is provided with at least one passage in fluid communication from the back pressure chamber to a low pressure region; the passage is configured such that: the passage is opened when the pressure in the back pressure chamber is lower than the pressure of the low pressure region, and is closed when the pressure in the back pressure chamber is higher than or equal to the pressure of the low pressure region. The scroll expander can avoid the problem of being unable to be started and to operate normally; and the scroll expander is simple in structure, easy to process and manufacture, and high in cost effectiveness.

A pneumatic control device includes a base seat unit, a cylinder unit and a time-delay unit. The cylinder unit is mounted the base seat unit, and is able to drive rotational movement. The time-delay unit is mounted to the base seat unit, and includes sequentially interconnected delay switch, flow-limiting valve, pressure accumulator and a control valve. The delay switch is operable to move between an action position whereat the cylinder unit drives the rotational movement, and a non-action position. When the delay switch is moved to the non-action position, the cylinder unit keeps driving the rotational movement for a period of time and then stops.

A turbomachine that can be operated as a motor and as a pump, having an axially fixedly mounted shaft, including a power section with rotating inlet and outlet and an associated controller. Because the axial forces (Fgx) have been made independent of the sense of rotation the turbomachine is significantly more reliable, and because the sealing forces have been adjusted it has significantly greater reliability (η) in both running directions. It can be operated with fluids and gases. The turbomachine can be extended by adding a control device and a drive for the control device so as to provide a freewheel function, a braking function and/or blocking function, and so as to shift, modify and optimize the characteristic curves across the entire control range. In both the clockwise and anticlockwise directions the turbomachine has in principle the same properties, although these can be modified and optimized by the control device.

A compound engine system includes a rotary engine with rotating chambers, a compressor section in successive communication with the rotating chambers, and a turbine section in successive communication with the rotating chambers. The turbine section has an output shaft. The output shaft and the engine shaft are drivingly engaged to each other and wherein the turbine section has a power output corresponding to from 20% to 35% of a total power output of the compound engine system. A method of compounding power in a compound engine system is also discussed.

A scroll expander, comprising: a housing; and an expansion mechanism provided in the housing. A back pressure chamber in fluid communication with a medium pressure chamber is provided in the expansion mechanism and is provided with at least one passage in fluid communication from the back pressure chamber to a low pressure region; the passage is configured such that: the passage is opened when the pressure in the back pressure chamber is lower than the pressure of the low pressure region, and is closed when the pressure in the back pressure chamber is higher than or equal to the pressure of the low pressure region. The scroll expander can avoid the problem of being unable to be started and to operate normally; and the scroll expander is simple in structure, easy to process and manufacture, and high in cost effectiveness.