Patent Publication Number: US-2015059333-A1

Title: Energy conversion and associated apparatus

Description:
FIELD OF THE INVENTION 
     The present invention relates to improved energy conversion and associated apparatus, particularly, but not exclusively, to an improved motor. 
     BACKGROUND TO THE INVENTION 
     The majority of engines presently in use are reciprocating piston, internal combustion engines. The internal combustion engine works on the principle of a regulated fuel mixture being ignited by a spark in an enclosed chamber. The production of power in an internal combustion engine is combined with fuel combustion and is restricted to every one stroke in four within a combined space. 
     Whilst being reliable, the internal combustion engine can have relatively poor fuel efficiency, high manufacturing costs and can cause significant environmental pollution. Increasingly stringent emission requirements have necessitated innovations such as catalytic converters, high pressure injection systems, synthetic lubrication oils and highly refined crude oil based fuels, all adding to the manufacturing and running costs. 
     The external combustion engine operates differently to the internal combustion engine in that combustion of the regulated fuel mixture takes place continuously within its own combustion chamber separately from the power production chamber. The energy transfer from the combustor to the power production/working chamber is enabled by the working fluid via heat exchangers. 
     The external combustion engine has reduced toxic emissions from the internal combustion engine, and the optimised fuel efficiency enables the use of less refined fuels and results in lower cost fuels. The external combustion engine, as there is no explosion involved, is quieter than the internal combustion engine. 
     However, the external combustion engine has drawbacks; such as oil degradation, heat exchanger contamination, high friction levels, high volume/weight/cost levels and low heater exchanger system efficiency. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the invention there is provided an apparatus for providing mechanical energy, the apparatus comprising 
     a motor for providing mechanical energy, the motor comprising at least one chamber for receiving a fluid to be heated and/or combusted and/or compressed and/or expanded; and 
     an amplified stimulated emission radiation source (e.g. a laser and/or a maser) for supplying radiation to the chamber. 
     The radiation may be supplied to the chamber to heat the fluid. The apparatus may be configured to heat the fluid in the chamber with the radiation from the amplified stimulated emission radiation source. 
     The radiation may be supplied to the chamber to preheat the fluid. The apparatus may be configured to preheat the fluid in the chamber with the radiation from the amplified stimulated emission radiation source. For example, the apparatus may be configured to preheat the fluid in the chamber with the radiation from the amplified stimulated emission radiation source prior to ignition of the fluid. 
     The radiation may be supplied to the chamber to heat the chamber. The apparatus may be configured to heat the chamber with the radiation from the amplified stimulated emission radiation source. For example, the radiation may be supplied to the chamber prior to and/or during and/or shortly after starting the motor (e.g. to bring the chamber and/or fluid up to a working temperature, such as when the motor has become cold through inoperation). The apparatus may be configured to supply radiation to the chamber prior to and/or upon start-up. 
     The radiation may be supplied to the chamber to ignite the fluid. The apparatus may be configured to ignite the fluid in the chamber with the radiation from the amplified stimulated emission radiation source. 
     The radiation may be supplied to the chamber to maintain the chamber. The apparatus may be configured to maintain the chamber with the radiation from the amplified stimulated emission radiation source. For example, the apparatus may be configured to clean the chamber with the radiation from the amplified stimulated emission radiation source, such as by ablation of a surface of the chamber. 
     The fluid may comprise an inert fluid. The fluid may comprise water and/or steam. The steam may comprise saturated steam. The steam may comprise wet steam. 
     The fluid may comprise a combustible fluid. The combustible fluid may comprise hydrogen. 
     The motor may comprise an internal combustion engine. 
     The motor may comprise an external combustion engine. The motor may be configured to compress a fluid in the chamber, such as with a piston. 
     The motor may comprise a cylinder defining the chamber. The piston may define an end wall of the chamber. 
     The motor may be configured to provide the amplified stimulated emission radiation to the chamber for a predetermined interval. The motor may be configured to provide the amplified stimulated emission radiation to the chamber at a predetermined phase or stage of a chamber cycle. For example, where the chamber is a cylinder chamber operable with a piston, the motor may be configured to provide the amplified stimulated emission radiation to the chamber when the piston reaches a predetermined position, such as top dead centre. For example, the motor may comprise a control system (e.g. comprising a switch and/or a timer and/or an electronic controller) such that the radiation source and/or a radiation guide and/or a radiation inlet is activated at a predetermined piston position. 
     The radiation may comprise a wavelength configured to heat the fluid. For example, where the fluid is steam, the laser may comprise a wavelength of about 1000 nm. 
     The radiation may comprise a wavelength configured to clean the chamber. For example, the radiation may comprise laser radiation with a low absorption depth, such as a low absorption depth in a chamber surface. 
     The radiation source may be configured to provide radiation with a wavelength/s in accordance with a surface property of the chamber (e.g. for low absorption depth). 
     The radiation may comprise multiple wavelengths. Multiple wavelengths may enable different absorption rates. Accordingly, the intensities of radiations at different wavelengths may vary along a path of the radiation through the chamber. For example, radiation at a first wavelength may be more readily absorbed by the fluid, such that the first wavelength may be used to radiate (e.g. heat) the fluid in a first portion of the chamber; and a second wavelength may be used to radiate the fluid in a second portion of the chamber. The first portion may correspond to a first section of a beam path. The second portion may correspond to a second section of a beam path. 
     The radiation may be divergent. 
     The radiation may comprise single spatial mode radiation. 
     The radiation may comprise multiple spatial mode radiation. 
     The radiation may comprise pulsed radiation and/or scanned radiation. For example, the apparatus may be configured to provide scanned radiation across the chamber. The apparatus may be configured to radially and/or circumferentially and/or spirally scan the radiation. 
     The motor may comprise the radiation source. 
     Alternatively the radiation source may be remote from the motor. 
     The motor may comprise a beam splitter. 
     The motor may comprise a radiation guide. 
     The motor may comprise a plurality of chambers. Each chamber may comprise a discrete radiation source. Alternatively, the motor may be configured to supply radiation from a single radiation source to multiple chambers. The motor may be configured to supply radiation from a single radiation source to multiple chambers sequentially. For example, the motor may be configured to selectively guide radiation from a single radiation source to each chamber depending on a phase of each chamber. The motor may be configured to sequentially radiate fluid in sequential chambers, such as adjacent chambers. The motor may be configured to simultaneously radiate fluid in multiple chambers. 
     The motor may comprise an external combustion compartment. For example, the motor may comprise a hydrogen burner. The motor may be configured to supply an exhaust fluid from the external combustion compartment to the fluid chamber. For example, the motor may comprise an inlet fluid means, such as an inlet pump and/or an inlet fan, for supplying fluid to a chamber inlet. 
     The motor may be configured to circulate the fluid (which may be a heatable fluid). The motor may comprise an exhaust fluid means, such as an exhaust pump and/or an exhaust fan, for directing chamber exhaust fluid away from a chamber outlet. 
     The motor may be configured to recirculate the fluid, such as directing chamber exhaust fluid to a chamber inlet. 
     Energy (e.g. heat) from the internal and/or external combustion engine may be used to heat and/or pressurise the fluid supplied to the chamber (e.g. to heat the fluid in the chamber, such as to pressurise the fluid). 
     In use, hydrogen may be supplied to the hydrogen burner, such that steam is generated. The steam may be supplied to the fluid chamber, such as via an inlet port by an inlet fan. The chamber may shrink. For example, the chamber may be compressed, such as by a reciprocating piston. The radiation source may be activated to supply radiation to the chamber. The radiation in the chamber may heat the steam. The pressure of the steam in the chamber may increase such that the piston is forced to reciprocate (down). Accordingly mechanical work may be harnessed from the piston. For example, the piston may be connected to a crank shaft such that the crank shaft is rotated by the action of the piston. 
     The maser may comprise a hydrogen maser. 
     The amplified stimulated emission radiation source may be battery-powered. The amplified stimulated emission radiation source may be generator-powered. Energy output from the internal and/or external combustion engine may be used to power the amplified stimulated emission radiation source. 
     The motor may be configured to distribute radiation throughout the chamber. 
     The motor may be configured to distribute the radiation evenly. 
     The motor may be configured to concentrate the radiation. 
     The motor may be configured to concentrate the radiation in a predetermined area or predetermined volume of the chamber. 
     The motor may be configured to distribute the radiation in the chamber according to a distribution of fluid in the chamber. 
     The motor may be configured to heat the fluid in the chamber. 
     The motor may be configured to heat the fluid evenly. 
     The motor may be configured to sequentially radiate fluid in different portions of the chamber. The motor may be configured to progressively radiate fluid in different portions of the chamber. The motor may be configured to progressively radially radiate fluid in different portions of the chamber. The motor may be configured to spirally radiate fluid in different portions of the chamber. The motor may be configured to divergently radiate fluid in different portions of the chamber. The motor may be configured to convergently radiate fluid in different portions of the chamber. 
     The motor may be configured to radiate fluid within the chamber according to a change in volume of fluid in the chamber. For example, the motor may be configured to radiate fluid in a first portion of the chamber during a first stage of radiation, such as during a reduction in the volume of the chamber (e.g. during a first stage of compression by the piston). The motor may be configured to radiate fluid in a second portion of the chamber during a second stage of radiation, such as when the piston is at top dead centre, or when the chamber comprises a minimum volume. 
     The motor may comprise a filter. The motor may comprise a filter to filter fluid at and/or prior to chamber entry. Additionally or alternatively, the motor may comprise a filter to filter fluid upon and/or after chamber exit. 
     The motor may comprise a motor inlet for receiving fluid (e.g. combustible fluid). The motor may comprise a motor outlet (e.g. exhaust valve) for releasing fluid (e.g. a combusted fluid and/or an uncombusted fluid; and/or a product or component thereof). 
     The motor may be configured to expel fluid form the chamber at shut-down. Expelling fluid from the chamber at shut-down may prevent a formation of fluid condensation within the chamber. 
     The motor may be configured to heat the chamber and/or fluid at start-up. Heating the fluid and/or the chamber at start-up may allow compensation of any temperature and/or pressure decrease due to a period of inoperation of the motor. 
     According to a further aspect of the invention there is provided a method of providing mechanical energy, the method comprising: 
     supplying radiation from an amplified stimulated emission radiation source to a chamber of a motor; 
     heating and/or igniting and/or pressurising a fluid in the chamber with the radiation; and/or 
     heating and/or maintaining the chamber with the radiation. 
     According to a further aspect of the invention there is provided a motor chamber for providing mechanical energy, the chamber being for receiving a fluid to be heated and/or combusted and/or compressed and/or expanded, wherein the chamber is configured to distribute radiation from an amplified stimulated emission radiation source (e.g. a laser and/or a maser) to heat and/or combust and/or pressurise the fluid and/or to radiate the chamber. 
     The chamber may be configured to distribute radiation throughout the chamber. 
     The chamber may be configured to distribute the radiation evenly. 
     The chamber may be configured to concentrate the radiation. 
     The chamber may be configured to concentrate the radiation in a predetermined area or predetermined volume of the chamber. 
     The chamber may be configured to distribute the radiation in the chamber according to a distribution of fluid in the chamber. 
     The chamber may be configured to heat the fluid in the chamber. 
     The chamber may be configured to heat the fluid evenly. 
     The chamber may comprise a cylinder chamber. The chamber may be defined by a cylinder. The chamber may be defined by a cylinder and a piston. 
     The chamber may comprise at least one side wall. The chamber may comprise an end wall. The chamber may comprise a moveable wall, such as a piston crown or head. 
     The chamber may comprise a fluid inlet port. The chamber may comprise a fluid outlet port. 
     The fluid inlet and/or outlet port may be configured to be in fluid communication with the chamber according to a control system. The control system may comprise a position of the piston and/or a stage of radiating the fluid in the chamber. 
     The chamber may be configured to sequentially radiate fluid in different portions of the chamber. The chamber may be configured to progressively radiate fluid in different portions of the chamber. The chamber may be configured to progressively radially radiate fluid in different portions of the chamber. The chamber may be configured to spirally radiate fluid in different portions of the chamber. The chamber may be configured to divergently radiate fluid in different portions of the chamber. The chamber may be configured to convergently radiate fluid in different portions of the chamber. 
     The chamber may be configured to radiate fluid within the chamber according to a change in volume of fluid in the chamber. For example, the chamber may be configured to radiate fluid in a first portion of the chamber during a first stage of radiation, such as during a reduction in the volume of the chamber (e.g. during a first stage of compression by the piston). The chamber may be configured to radiate fluid in a second portion of the chamber during a second stage of radiation, such as when the piston is at top dead centre, or when the chamber comprises a minimum volume. 
     The first and/or second portion/s of the chamber may be an annular portion/s. The first and/or second portion/s of the chamber may be a radial portion/s. The first and/or second portion/s of the chamber may be a segment portion/s. The first and/or second portion/s of the chamber may be an axial portion/s. The first and/or second portion/s of the chamber may be a spiral portion/s. The first and/or second portion/s of the chamber may be a helical portion/s. The first and/or second portion/s of the chamber may be a central portion/s. The first portion may comprise the second portion. 
     The chamber may comprise a concave surface. The chamber may comprise a concave surface configured to concentrate the radiation, such as towards a central portion of the chamber. The moveable wall and/or the chamber end wall and/or the side wall/s may comprise a concave surface. The chamber may comprise a convex surface. The chamber may comprise a convex surface configured to spread the radiation. The moveable wall and/or the chamber end wall and/or the side wall/s may comprise a convex surface. 
     The moveable wall may comprise an axially and/or laterally and or rotationally asymmetric profile relative to a longitudinal axis of the chamber. The moveable wall may comprise an axially and/or laterally and or rotationally symmetric profile relative to a longitudinal axis of the chamber. 
     The chamber may comprise a reflective surface. For example, the chamber may comprise a mirror configured to reflect the radiation. The moveable wall and/or the chamber end wall and/or the side wall/s may comprise the reflective surface. The reflective surface may be angled with respect to the incident radiation beam (e.g. to redirect the radiation beam towards a non-radiated chamber portion, such as away from a chamber radiation inlet). 
     The chamber may comprise a profiled surface, such as a textured or grooved surface (e.g. moveable end wall and/or the chamber end wall and/or the side wall/s). The magnitude (or amplitude) and/or pitch of the profiled surface may be configured according to the radiation wavelength/s. For example, the profiled surface may comprise a structure with a pitch and/or order of magnitude larger than the radiation wavelength/s. The profiled surface may comprise a structure with a pitch and/or order of magnitude larger similar to the radiation wavelength/s. The profiled surface may comprise a structure with a pitch and/or order of magnitude less than the radiation wavelength/s. 
     The magnitude and/or pitch of the profiled surface may be configured according to the beam diameter and/or width. For example, the profiled surface may comprise a structure with a pitch and/or order of magnitude larger than the beam diameter and/or width. The profiled surface may comprise a structure with a pitch and/or order of magnitude larger similar to the beam diameter and/or width. The profiled surface may comprise a structure with a pitch and/or order of magnitude less than the beam diameter and/or width. 
     The chamber may be configured to be ablated by the radiation. For example, the chamber may be configured such that radiation reaches substantially the entire surface/s of the chamber. The chamber may be configured such that the chamber surface/s receives a substantially homogenous dosage of radiation. 
     The chamber may be configured such that the chamber surface/s receive a radiation dosage corresponding to a surface property. For example, the chamber may be configured such that a first chamber portion prone to fouling or contaminant concentration (such as a transition—e.g. an edge or area adjacent an outlet) receives a higher radiation dosage than a second chamber portion less prone to fouling or contaminant concentration (such as an intermediate sidewall portion). 
     The chamber may be microscopic. 
     The chamber may be nanoscopic. 
     The invention includes one or more corresponding aspects, embodiments or features in isolation or in various combinations whether or not specifically stated (including claimed) in that combination or in isolation. For example, it will readily be appreciated that features recited as optional with respect to the first aspect may be additionally applicable with respect to the other aspects without the need to explicitly and unnecessarily list those various combinations and permutations here. 
     In addition, corresponding means for performing one or more of the discussed functions are also within the present disclosure. 
     It will be appreciated that one or more embodiments/aspects may be useful in providing mechanical energy. 
     The above summary is intended to be merely exemplary and non-limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present invention will now be described with reference to the accompanying drawings in which: 
         FIG. 1  is a schematic of an apparatus according to a first embodiment of the present invention; 
         FIG. 2  is a partial view of the apparatus of  FIG. 1 ; 
         FIG. 3  is a view of a cylinder of the apparatus of  FIG. 1  in a first configuration; 
         FIG. 4  is a view of a cylinder of the apparatus of  FIG. 1  in a second configuration; 
         FIG. 5  is a view of a cylinder of the apparatus of  FIG. 1  in a third configuration; 
         FIG. 6  is a view of a cylinder of the apparatus of  FIG. 1  in a fourth configuration; 
         FIG. 7  is a cross-sectional view of a cylinder in accordance with an embodiment of the invention; 
         FIG. 8  is a cross-sectional view of the cylinder of  FIG. 7 , showing a portion of a radiation distribution in a cylinder chamber; 
         FIG. 9  is a plan view of the cylinder of  FIG. 7 , showing a portion of a radiation distribution in a cylinder chamber; 
         FIG. 10  is a graph showing a radiation distribution in a cylinder chamber; 
         FIG. 11  is a cross-sectional view of a cylinder in accordance with an embodiment of the invention, showing a portion of a radiation distribution in a cylinder chamber; 
         FIG. 12  is a cross-sectional view of a cylinder in accordance with an embodiment of the invention, showing a portion of a radiation distribution in a cylinder chamber; and 
         FIG. 13  is a perspective view of a cylinder in accordance with an embodiment of the invention, showing an indicative surface of a piston head in a cylinder chamber. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a schematic of an apparatus for providing mechanical energy, generally indicated by reference  10 , according to a first embodiment of the present invention. The apparatus  10  for providing mechanical energy comprises a motor  11  for providing mechanical energy. The motor  11  comprises a chamber  17  for receiving a fluid to be heated. An amplified stimulated emission radiation source (not shown in  FIG. 1 ) is provided for supplying radiation to the chamber  17 . 
     The apparatus  10  further comprises an inlet fan  14  to direct fluid towards a series of cylinders  16 . In the embodiment shown, the apparatus  10  comprises a series of five radially-arranged cylinders  16   a,    16   b,    16   c,    16   d,    16   e;  each cylinder comprising a chamber  17   a,    17   b,    17   c,    17   d,    17   e.  The apparatus further comprises an exhaust fan  18  to direct fluid away from the series of cylinders  16 . 
     In the embodiment shown, the apparatus  10  further comprises a combustion engine in the form of a hydrogen burner  20 . Accordingly, hydrogen and oxygen (or air) are supplied to the apparatus  10  via respective inlets  22 ,  24 . 
     The hydrogen is combined with the oxygen to provide steam to the inlet fan  14 . As shown in  FIG. 2 , the steam is fed to the cylinders  16  via respective cylinder inlets  26   a,    26   b,    26   c,    26   d,    26   e;  each inlet comprising a one-way valve. Each inlet  26   a,    26   b,    26   c,    26   d,    26   e  is formed and arranged such that steam is only fed to the respective cylinder  16   a,    16   b,    16   c,    16   d,    16   e  at an appropriate stage of the cylinder cycle. That is, steam is fed to the cylinder  16   a,    16   b,    16   c ,  16   d,    16   e  when a cylinder piston moves towards a lower portion of the cylinder  16   a,    16   b,    16   c,    16   d,    16   e  (e.g. intake stroke). 
     The steam is exhausted from the cylinders  16  via respective cylinder outlets  28   a,    28   b,    28   c,    28   d,    28   e;  each outlet comprising a one-way valve. Each outlet  28   a,    28   b,    28   c,    28   d,    28   e  is formed and arranged such that steam is only exhausted from the respective cylinder  16   a,    16   b,    16   c,    16   d,    16   e  at an appropriate stage of the cylinder cycle. That is, steam is only exhausted from the cylinder  16   a,    16   b,    16   c,    16   d,    16   e  when a cylinder piston moves towards an upper portion of the cylinder  16   a,    16   b,    16   c,    16   d,    16   e  during an exhaust stroke. 
     The exhaust fan  18  draws exhaust steam away from the cylinder outlet  28   a,    28   b,    28   c,    28   d,    28   e.  Cowling  30  within the motor housing  32  directs the exhaust steam towards the inlet fan  14  where the steam is recirculated through the cylinders  16   a,    16   b,    16   c,    16   d,    16   e.    
       FIG. 3  is a view of the cylinder  16  of the apparatus of  FIG. 1  in a first configuration. The piston  34  is at bottom dead centre and steam has been fed into the cylinder  16  via the cylinder inlet (not shown in  FIGS. 3 to 6 ). The piston  34  starts a compression stroke as indicated by the arrow. As the piston  34  nears top dead centre, as shown in  FIG. 4 , a laser source  36  is activated such that a laser beam is directed into the cylinder chamber via a laser inlet. In the embodiment shown, the laser source  36  and the laser inlet are axially located relative to the cylinder  16 . 
     In the configuration of  FIG. 4 , the steam in the cylinder  16  is heated by the laser radiation. Accordingly the temperature of the steam is increased and consequently the pressure in the cylinder  36 . The increased pressure in the cylinder  36  forces the piston  34  towards bottom dead centre as shown in  FIG. 5 , whereby mechanical energy is output from the cylinder  16 , such as via a connecting rod to a crankshaft (not shown). In the embodiment shown, once the piston has reached the bottom dead centre position of  FIG. 6 , an exhaust stroke and intake stroke are completed prior to completing a further compression and power cycle as described with reference to  FIGS. 3 to 5 . In alternative embodiments, it will be appreciated that the motor may not comprise an exhaust stroke and that a same fluid, such as steam, may be recompressed and reheated within the cylinder  16  to generate a further power stroke. 
       FIG. 7  shows a cross-sectional view of a cylinder  116  in accordance with an embodiment of the invention. In the embodiment shown, the cylinder  116  comprises a cylinder head  140  and a piston head  142 , each comprising a respective concave surface  144 ,  146 .  FIG. 8  shows a portion of a radiation distribution in the cylinder chamber  117  of  FIG. 7  at top dead centre. The concave surfaces  144 ,  146  are configured such that a volume of steam in the cylinder chamber  117  is radially concentrated towards the centre of the cylinder  116 . Accordingly, the volume of steam is concentrated in a same portion of the cylinder  116  as a laser beam  150  upon activation as the piston  134  reaches top dead centre. The cylinder  116  further comprises a cylindrical side wall  148 , which also constitutes a concave surface such that the laser beam is consistently redirected towards the central portion of the cylinder chamber  117 ; both laterally and axially by the concave surfaces  144 ,  146 ,  148 . 
       FIG. 9  is a plan view of the cylinder  116  of  FIG. 7 , showing a portion of radiation distribution in the cylinder chamber  117 . The concentration of the laser beam  150  towards the centre  152  of the cylinder chamber  117  due to the reflections from the concave surfaces  144 ,  146 ,  148 .  FIG. 10  graphically shows a radiation distribution across the cylinder chamber  117  according to radial distance from the centre  152 . Accordingly, the laser beam  150  follows a path proportional to the distribution of steam in the cylinder chamber  117 . 
       FIG. 11  shows a cross-sectional view of an alternative cylinder  216  in accordance with an embodiment of the invention, showing a portion of a radiation distribution in a cylinder chamber  217 . In the embodiment shown, the cylinder head  240  comprises a concave surface  244  and the piston head  242  comprises a convex surface  246 . The cylinder  216  further comprises a cylindrical side wall  248 , which also constitutes a concave surface. The cylinder chamber  217  is configured such that the laser beam  250  is directed towards peripheral portions  254  of the chamber  217 , away from the central portion  252 . Accordingly, the laser beam  250  follows a path proportional to the distribution of steam in the cylinder chamber  217 . 
       FIG. 12  is a cross-sectional view of a cylinder  316  in accordance with an embodiment of the invention, showing a portion of a radiation distribution  350  in a cylinder chamber  317 . In the embodiment shown, the cylinder head  340  and piston head  342  comprise respective profiled surfaces  344  and  346 . The profiled surfaces  344 ,  346  are configured according to the wavelength of the laser beam  350 . The pitch of the profiled surfaces  344 ,  346  is such that the radiation beam  350  is dispersed throughout the chamber  317  to distribute the radiation evenly throughout the chamber  317 . 
     A schematic example of a profiled surface  446  of a piston head  442  is shown in  FIG. 13 . The cylinder head  446  has been finely machined with a fine spiral pattern  470 . The cylinder head  340  is shown with a circumferentially-mounted laser source  436 . 
     It will be appreciated that the system may operate with a continuous supply of combustible fluid. It will also be appreciated that a system may operate with a closed circuit of heatable fluid. For example, an initial combustion process can provide the recirculatable combustible fluid until a desired pressure threshold is attained within the motor; at which stage no further fluid or fluid components need be supplied to the motor. 
     In alternative embodiments, the motor may utilise the laser source at discrete intervals to maintain the cylinder. For example, the laser source may be operable when the motor is inoperable, such as to clean and/or flush the cylinder chambers. The laser source may be directed into the cylinder chambers to ablate the cylinder chamber surfaces. The motor may be configured to routinely activate the laser source for such operation, such as upon shut-down of the motor and/or periodically. 
     It will be appreciated that any of the aforementioned apparatus may have other functions in addition to the mentioned functions, and that these functions may be performed by the same apparatus. 
     The applicant hereby discloses in isolation each individual feature described herein and any combination of two or more such features, to the extent that such features or combinations are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art, irrespective of whether such features or combinations of features solve any problems disclosed herein, and without limitation to the scope of the claims. The applicant indicates that aspects of the present invention may consist of any such individual feature or combination of features. It should be understood that the embodiments described herein are merely exemplary and that various modifications may be made thereto without departing from the scope of the invention. For example, where a four stroke process is described, it will be appreciated in alternative embodiments/modes of use, the cylinder may operate with alternative cycles, such as a two stroke process. Similarly, where a laser source has been shown, it will be appreciated that additional or alternative radiation may be supplied to the cylinder chamber by a maser source, such as a hydrogen maser.