FLUIDS` MECHANICS in BIOLOGICAL SYSTEMS

Laurea Magistralis
in MEDICINE
and SURGERY
Corso di Laurea
Specialistica
in
MEDICINA
e CHIRURGIA
“HARVEY”
corso integrato
FISICA - disciplina
FISICA
Integrated
Course/Discipline:
PHYSICS
FLUIDS’ MECHANICS
in
BIOLOGICAL SYSTEMS
Ist part
- CARDIOVASCULAR SYSTEM
- RESPIRATORY SYSTEM
- LYMPHATIC SYSTEM
- OTHER SMALLER CANALIZATIONS WITH FLUID MOTION
01/14
FLUIDS MECHANICS in
BIOLOGICAL SYSTEMS
human biological
phenomenon description
how does it work ?
fluid mechanics in
biological systems
PHYSICS
basis
D. SCANNICCHIO 2009
02/14
CARDIOVASCULAR
SYSTEM
HEART
CAPILLARIES
Capillari
ARTERY
VEIN
FLUID: liquid (blood)
DUCTS: blood vessels
isothermal (t = 37°C)
variable pressure
fluid density constant (not compressible)
schema del circuito chiuso :
4
mmHg
CUORE
HEART
RA VD
RV
AD
LA VS
LV
AS
25
mmHg
5 litri/min
5 liters/min
100
mmHg
8
mmHg
POLMONI
LUNGS
5 liters/min
5 litri/min
GRANDE CIRCOLO
10
mmHg
40
mmHg
CAPILLARIES
CAPILLARI
D. SCANNICCHIO 2009
03/14
RESPIRATORY
SYSTEM
CARTILAGINOUS
RINGS
TRACHEA
CARTILAGINOUS
PLATES
CATHETER
RIBS
MAIN LEFT
BRONCUS
MAIN RIGHT
BRONCUS
MAIN LEFT
BRONCUS
LUNG’S ROOT
VISCERAL PLEURA
SECONDARY
BRONCUS
SECONDARY
BRONCUSES
TERTIARY BRONCUS
SMALL BRONCUSES
FLUID: gas mixture (air)
DUCTS: broncuses
isothermal (t = 37°C)
variable pressure
fluid density variable (compressible)
D. SCANNICCHIO 2009
BRONCHIOLES
TERMINAL
BRONCHIOLE
BREATHING
BRONCHIOLE
LUNG LOBULE
ALVEOLUS
04/14
RESPIRATORY
SYSTEM
TONSIL
CERVICAL
LYMPH
NODES
LIMPHATIC
RIGHT DUCT
THYMUS
THORACIC
DUCT
CHYLE
CISTERN
LUMBAR
LYMPH
NODES
UPPER LIMB LYMPHATICS
THORACIC DUCT
(LEFT LYMPHATIC)
AXILLARY LYMPH
NODES
BREAST LYMPHATIC
SPLEEN
MUCOSE ASSOCIATED
LYMPHOID TISSUE
(MALT)
LYMPHATIC
SYSTEM
FLUID: liquid (lymph)
DUCTS: lymphatic vessels
isothermal (t = 37°C)
variable pressure
fluid density constant
(not compressible)
PELVIC LYMPH NODES
INGUINAL LYMPH
NODES
BLOOD CAPILLARIES
ARTERIOLE
SMOOTH MUSCLES
LYMPHATIC
CAPILLARY
LOWER LIMB
LYMPHATICS
ENDOTHELIAL
CELLS
VENULA
D. SCANNICCHIO 2009
INTERSTITIAL
LIQUID
LOOSE
CONNECTIVE
TISSUE
TISSUES, BLOOD CAPYLLARIES AND LYMPHATIC CAPILLARIES
05/14
FRACTALS
Which is the reason for the particular structure
of the circulation, respiratory and lymphatic
systems (like tree branchings)?
Nature requirments:
maximize the suface (for substances exchange - atoms,
molecules and ions) and minimize the volume and the
system’s biological material .
solution: fractal geometry !!
large surface in a limited volume
(saving biological material)
D. SCANNICCHIO 2007
14
7
FRACTALS
solution: fractal geometry !!
Geometrical patterns self copying over and over on an
ever greater scale: the repetitive shape does not
change even if it is scaled up very much (similarity
ratio on different scales).
Fractal images have fractional dimensions.
further important advantage:
the system can grow in structures selfcopying
D. SCANNICCHIO 2007
15
8
FRACTALS
blood circulation system
D. SCANNICCHIO 2007
respiratory system
15
9
FRACTALS
some similar examples:
tree
D. SCANNICCHIO 2007
fern leafes
roman cabbage
10
15
KIDNEY
URETER/URETHRA
URETER
MEDIAN UMBILICAL LIGAMENT
URETER
BLADDER
LATERAL
UMBILICAL
LIGAMENT
URETHRAL
OPENINGS
URETHRA
WRINKLES
TRIGONE CENTER
NECK
PROSTATE
EXTERNAL
DIAPHRAGM
SPHINCTER
(IN UROGENITAL
DIAPHRAGM)
PROSTATIC URETHRA (ONLY MAN)
MEMBRANEOUS URETHRA
FLUID: liquid (urine)
DUCTS: ureter, bladder, urethra
isothermal (t = 37°C)
variable pressure
fluid density constant (not compressible)
D. SCANNICCHIO 2009
06/14
KIDNEY’S DUCTS
CORTICAL
NEPHRON
LUXTA MEDULLARY
NEPHRON
FLUID: liquid (urine)
DUCTS: tubulus,
collector duct
CORTICAL
MEDULLARY
isothermal (t = 37°C)
variable pressure
fluid density = constant
(not compressible)
DRAIN DUCT
KIDNEY
PAPILLA
CALYX MINOR
D. SCANNICCHIO 2009
PAPILLARY DUCTS
07/14
COCHLEA
COCHLEA BONE
WALL
VESTIBULAR
DUCT
SPIRAL
GANGLION
COCHLEAR
DUCT
CORTI’S
ORGAN
OVALFinestra
WINDOW ovale
BASIC
MEMBRANE
TYMPANIC DUCT
CORTI’S
ORGAN
Organo
del Corti
D. SCANNICCHIO 2009
FLUID: liquid (endolymph)
DUCTS: timpanic and vestibular ducts,
isothermal (t = 37°C)
variable pressure (sound waves)
fluid density = constant (not compressible)
08/14
LABYRINT’s DUCTS
SEMICIRCULAR
DUCTS
ENDOLYMPHATIC
DUCT
ENDOLYMPHATIC
BAG
VESTIBULAR BRANCH
(VIII)
MACULES
SACCULUS
UTRICLE
AMPULLA
cellule
HAIRYcapellute
CELLS
D. SCANNICCHIO 2009
OTOLITHS
otoliti
FLUID: liquid (endolymph)
DUCTS: semicircular ducts,
isothermal (t = 37°C)
variable pressure
fluid density = constant (not compressible)
09/14
CARDIOVASCULAR
SYSTEM
• DESCRIPTION
• PRESSURE, VELOCITY and FLOW RATE
• CONTINUITY EQUATION
• FLUIDODYNAMICS and SUBSEQUENT APPROXIMATIONS
• MOTION REGIMES and CONSEQUENCES
• CARDIAC WORK and POWER
• BLOOD VISCOSITY
• DUCTS ELASTIC EFFECTS on MOTION
• PULSATION’S EFFECTS on MOTION
• ANALOGICAL MODELS and DEVELOPMENTS
• CONCLUSION
D. SCANNICCHIO 2009
10/14
LESSONS’ PROGRAM
human biological
phenomenon description
how does it work ?
fluid mechanics in
biological systems
PHYSICS
basis
D. SCANNICCHIO 2009
11/14
CARDIOVASCULAR
SYSTEM
HEART
CAPILLARIES
Capillari
ARTERY
VEIN
general description
behaviour of the significant
physical quantities
blood pressure
(mercury millimeters (mmHg))
blood velocity (cm/s)
D. SCANNICCHIO 2009
12/14
BLOOD CIRCULATION SYSTEM
pressione
media
time mean pressure
POLMONI
LUNGS
VENA
VENA
CAVA
CAVA
time mean
velocity
velocità
media
(nel tempo)
AORTA
AORTA
CUORE
ARTERIES
VEINS
valvole
ARTERIE
VENE
ARTERIOLES
VENULES
ARTERIOLE
VENULE
CAPILLARIES
CAPILLARI
D. SCANNICCHIO 2009
(nel tempo)
AORTA
AORTA
ARTERIES
ARTERIE
ARTERIOLE
ARTERIOLES
CAPILLARI
CAPILLARIES
VENULE
VENULES
VENE
VEINS
VENA CAVA
VENA CAVA
13/14
BLOOD CIRCULATION SYSTEM
pressione
media
time mean pressure
(nel tempo)
time mean
velocity
velocità
media
(nel tempo)
velocità
media
mean velocity
–1
(cm s )
CUORE
HEART
AORTA
AORTA
ARTERIES
ARTERIE
ARTERIOLES
ARTERIOLE
CAPILLARIES
CAPILLARI
VENULES
VENULE
VEINS
VENE
VENA CAVA
VENA CAVA
CUORE
HEART
D. SCANNICCHIO 2009
pressione
media
mean pressure
(mmHg)
100
100÷40
40÷25
25÷12
12÷8
8÷3
2
??
50÷40
40÷10
10÷0.1
<0.1
<0.3
0.3÷5
5÷25
14/14